The invention related to metabolites of certain [1,4] diazepino [6,7,l-IJ]quinoline
derivatives and methods of preparation and use thereof
FIELD OF THE INVENTION
The present invention relates to metabolites of certain {1,4]diazepino[6,7,1-
quinoline derivatives, which are useful as antipsychotic and antiobesity agents, to
processes for their preparation, to pharmaceutical compositions containing them, and
to methods of using them.
BACKGROUND OF THE INVENTION
Schizophrenia affects approximately 5 million people. At present, the most
widespread treatments for schizophrenia are the 'atypical' antipsychotics, which
combine dopamine (D2) receptor antagonism with serotonin (5-HTaO receptor
antagonism. Despite the reported advances in efficacy and side-effect liability of
atypical antipsychotics over typical antipsychotics, these compounds do not
adequately treat all of the symptoms of schizophrenia and are accompanied by
problematic side effects including weight gain (Allison, D. B,, et. al., Am. J.
Psychiatry, 156:1686-1696,1999; Masand, P. S., Exp. Opin. Pharmacother. 1:377-
389,2000; Whitaker, R., Spectrum Life Sciences. Decision Resources. 2:1-9,2000).
Novel antipsychotics which are effective in treating the mood disorders or the
cognitive impairments in schizophrenia without producing weight gain would
represent a significant advance in the treatment of schizophrenia.
5-HT2C agonists and partial agonists represent a novel therapeutic approach
toward the treatment of schizophrenia. Several lines of evidence support a role for 5-
HTzc receptor agonism as a treatment for schizophrenia. Studies with 5-HT2C
antagonists suggest that these compounds increase synaptic levels of dopamine and
may be effective in animal models of Parkinson's disease (Di Matteo, V., et al.,
Neuropharmacology 37: 265-272,1998; Fox, S. H., et. ai., Experimental Neurology
151:3549,1998). Since the positive symptoms of schizophrenia are associated
with increased levels of dopamme, compounds with actions opposite those of 5-HTac
antagonists such as 5-HT2c agonists and partial agonists should reduce levels of
synaptic dopamine. Recent studies have demonstrated that 5-HT2C agonists
decrease levels of dopamine in the prefrontal cortex and nucleus accumbens (Millan,
M. J., et. at., Neuropharmacology 37:953-955,1998; Di Matteo, V., et. al.,
Neuropharmacology 38:1195-1205,1999; Di Giovanni, G., et. al., Synapse 35:53-
61,2000), brain regions that are thought to mediate critical antipsychotic effects of
drugs like clozapine. In contrast, 5-HT2C agonists do not decrease dopamine levels
in the striatum, the brain region most closely associated with extrapyramidal side
effects. In addition, a recent study demonstrates that 5-HT2c agonists decrease
firing in the ventral tegmental area (VTA), but not in substantia nigra. The differential
effects of 5-HT2c agonists in the mesolimbic pathway relative to the nigrostriatal
pathway suggests that 5-HT2C agonists will have limbic selectivity and will be less
likely to produce extrapyramidal side effects associated with typical antipsychotics.
Atypical antipsychotics bind with high affinity to 5-HT2c receptors and function
as 5-HT2C receptor antagonists or inverse agonists. Weight gain is a problematic
side effect associated with atypical antipsychotics such as clozapine and olanzapine
and it has been suggested that 5-HT2C antagonism is responsible for the increased
weight gain. Conversely, stimulation of the 5-HT2C receptor is known to result in
decreased food intake and body weight (Walsh et. al., Psychopharmacology 124:57-
73,1996; Cowen, P. J., et. al., Human Psychopharmacology 10:385-391,1995;
Rosenzweig-Lipson, S., et. al., ASPET abstract, 2000). As a result, 5-HT20 agonists
and partial agonists will be less likely to produce the body weight increases
associated with current atypical antipsychotics. Indeed, 5-HT2C agonists and partial
agonists are of great interest for the treatment of obesity, a medical disorder
characterized by an excess of body fat or adipose tissue and associated with such
comorbidities as Type II diabetes, cardiovascular disease, hypertension,
hyperiipidemia, stroke, osteoarthritis, sleep apnea, gal| bladder disease, gout, some
cancers, some infertility, and early mortality.
The compound (gaR.^aSH.S.BJ.g.ga.lO.H.I
cyclopenta[c][1,4]diazepine[6,7,1-//]quinoline (hereafter DCDQ):
is a potent 6-HT2C agonist. See related published applications W003/091250 and
US2004/0009970, each of which is incorporated by reference herein in its entirety.
DCDQ can also be effective in treating the mood disorders or the cognitive
impairments associated with schizophrenia. DCDQ is converted, in several in vitro
and in vivo models, into several metabolites. It can be seen that these metabolites
are of interest in treating those diseases, disorders, or conditions treatable by DCDQ,
itself as is or as a prodrug which converts to DCDQ. These metabolites could also
be useful for further studying the effects of DCDQ. This invention is directed to
these, as well as other, important ends.
SUMMARY OF THE INVENTION
Some embodiments of the invention include compounds formula I
(Figure Removed)
wherein:
for each Rn and Rn>, where n is 1 through 8:
each R" and Rn> is independently hydrogen, hydroxy, CH3C(O)-O-, -OS03H,
or -0-G; or
R and the corresponding Rn>, where n is 2,3, 4,6,7, or 8, taken together with
the carbon to which they are attached, form C=0; or
R" along with the corresponding Rn+1, where n is 1,2, 3,4, 5, or 7, taken
together form a double bond between the carbons to which they are attached, and
each corresponding Rn> and R(n+1)> is independently hydrogen, hydroxy, CH3C(0)-O,
-OSOaH.or-O-G;
G has the formula:
(Figure Removed)

wherein the nitrogen denoted with the symbol * can optionally form an Noxide;
X-Y is CH=N, CH=N(0), CH2N(O), C(O)NH orCR9HNR10;
R8 is hydrogen, hydroxyl, or-OSO3H;
R10 is hydrogen, acetyl, -SO3H, -G, or -C(O)-OG;
Z is hydrogen, hydroxy, -OSO3H, or -O-G;
with the proviso that when Z is hydroxy, then either (a) one of R1, R2, R3, R4,
R5, Rs, R7, R8, R9, and R10 is not hydrogen; or (b) X-Y is not CR9HNR10; and
with the further proviso that when X-Y is CHR9NR10, then at least one of Z, R1,
R2, R3, R\ R5, R6, R7, R8, R9, and R10 is not H.
In some 'embodiments, the invention provides compounds according to
Formula I, wherein at least one of Z and R1 through R8 is -OH.
In some embodiments, the invention provides compounds according to
Formula I wherein at least one of R1 through R6, R9, R10, and Z is -C(O)-0-G, -O-G,
or -G.
In some embodiments, the invention provides compounds according to
Formula I, wherein at least one of R1 through R9, and Z is -OSO3H.
In some embodiments, the invention provides compounds according to
Formula I, wherein X-Y is CR9HNR10, where R9 is H and R10 is -SO3H.
In some embodiments, the invention provides compounds according to
Formula I, wherein R" and corresponding Rn> taken together with the carbon to which
they are attached form C=O.
In some embodiments, the invention provides compounds according to
Formula I, wherein X-Y is C(O)NH.
In some embodiments, the invention provides compounds according to
Formula I, wherein X-Y is CH=N.
In some embodiments, the invention provides compounds according to
Formula I, wherein at least one of R" and its corresponding Rn+1, where n = 1-5,
together form a double bond between the carbons to which they are attached and
each Rn> and R(n+1)" is independently hydrogen, hydroxy, CH3C(O)-O, -OSO3H, or -OG.
In some embodiments, the Invention provides isolated or substantially pure
forms of compounds of Formula I, having at least 75% purity. In other embodiments,
the invention provides compounds of Formula I having at least 80% purity. In other
embodiments, the invention provides compounds of Formula I having at least 85%
purity. In other embodiments, the invention provides compounds of Formula I having
at least 90% purity. In other embodiments, the invention provides compounds of
Formula I having at least 95% purity.
In some embodiments, the invention provides pharmaceutical compositions
including compounds of formula I.
In some embodiments, the invention provides methods of treating conditions,
diseases, or disorders associated with 5HT2c by administering compounds of
Formula I or pharmaceutical compositions comprising compounds of Formula I to a
patient in need thereof.
In some embodiments, the invention provides a method of preparing a
compound of formula M6:
M6
comprising:
reacting Compound 6a:
where each L, L1, and L2 is a leaving group;
with DCDQ:
in the presence of a coupling reagent under conditions sufficient to
yield compound 7:
(Figure Removed)

and removing said leaving groups L1 and L2 to form compound M6.
In some embodiments, the invention provides methods wherein L has the
formula:
(Figure Removed)

In some embodiments, the invention provides methods wherein L1 and L2 are
independently selected from lower alkyl and acetyl, such as when L1 is methyl and
each L2 is acetyl.
Preferred coupling reagents are (Benzotriazol-1-
yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), N,N'-
Dicyclohexylcarbodiimide (DCC), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide
hydrochloride (EDO).
In some embodiments, the invention provides a method further comprising
deprotecting compound 7 by removing the L1 and L2 protecting groups of the
glucuronyl moiety of compound 7, thereby forming the M6 metabolite. In some
embodiments, the deprotecting step is performed in alcohol, preferably a lower alkyl
alcohol, in the presence of a base, preferably NaOH, LiOH, or KOH. In some
preferred embodiments, LiOH«H20 in MeOH/H2O/THF is used in a preferred ratio of
approximately 2.5:1.0:0.5. In some embodiments, the deprotection reaction is
carried out at 0 °C for 1 hour.
In some embodiments, the reaction of compound 6 with the coupling reagent
and DCDQ is carried out in the presence of an amine, preferably HOnig's base. This
reaction is preferably performed in a solvent, such as CH2CI2.
in some embodiments, compound 7 is subjected to column chromatography
purification prior to deprotection.
In some embodiments, the invention further provides for purifying the M6
metabolite.
In some embodiments, the invention provides methods where compound 6a
is prepared by removing the allyl protecting group of compound 5:
using a catalyst and a nucleophile, preferably morpholine. In some embodiments,
the catalyst is Pd(PPh3)4.
In some embodiments, the invention provides methods wherein compound 5
is prepared by reacting carboxylic acid 2:
HO
with DPPA under conditions sufficient to yield an acyl azide intermediate;
heating resultant acyl azide intermediate under conditions sufficient to yield
isocyanate 3:
;and
treating result of said heating step with 2,3,4,-triacetyH-hydroxyglucoronlc
(Figure Removed)

under conditions sufficient to yield compound 5. In some embodiments, the reacting
step is carried out in the presence of a base, preferably Et3N.
In some embodiments, the invention provides methods wherein compound 2
is prepared by reacting diphenic anhydride with excess allyl alcohol, preferably prop-
2-en-1-ol, in the presence of a catalyst, preferably DMAP.
These and other embodiments of the invention will be apparent to those of
skill in the art upon reading this disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowchart of proposed metabolic pathways of DCDQ identified in
the in vitro and in vivo studies.
FIG. 2 is a further flowchart of proposed metabolic pathways of DCDQ
identified in rat biliary excretion studies.
FIG. 3 is a further flowchart of proposed metabolic pathways of DCDQ
identified in mice.
FIG. 4 is a further flowchart of proposed metabolic pathways of DCDQ
identified in human plasma.
FIG. 5 depicts structures and NMR numbering schemes for DCDQ, M7, M9
and M13 as identified in the rat billiary excretion studies.
DETAILED DESCRIPTION OF THE INVENTION
In some aspects, this invention relates to metabolites of DCDQ, methods of
preparing them, and methods of using them to treat various disorders.
In some aspects, the present invention provides compounds of formula (I)
wherein:
for each Rn and Rn>, where n is 1 through 8:
each R" and Rn> is independently hydrogen, hydroxy, CH3C(O)-0,
-OSO3H, or -O-G; or
Rn and the corresponding Rn>, where n is 2, 3,4,6,7, or 8, taken
together with the carbon to which they are attached, form C=O; or
R" along with the corresponding R"*1, where n is 1,2, 3,4, 5, or 7,
taken together form a double bond between the carbons to which they are attached,
and each corresponding Rn' and R(n*1)> is independently hydrogen, hydroxy, CH3C(O)-
O,-OSO3H,or-O-G;
wherein the nitrogen denoted with the symbol * can optionally form an Noxide;
G has the formula:
CO2H ;
X-Y is CH=N, CH=N(0), CH2N(O), C(O)NH orCR9HNR10;
R9 is hydrogen, hydroxyl, or -OSO3H; and
R10 is hydrogen, acetyl, -SO3H, -G. or-C(O)-OG;
Z is hydrogen, hydroxy, -OSO3H, or -O-G, with the proviso that when Z is
hydroxy, then either (a) one of R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 is not
hydrogen; or (b) X-Y is not CR9HNR10;
with the further proviso that when X-Y is CHR9NR10, then at least one of Z, R1,
R2, R3, R4, Rs, R6, R7, R8, R9, and R10 is not H.
Methods for the preparation of DCDQ (i.e., the compound of Formula I where
X-Y is CHR9NR10 and each of Z, and R1 through R10 is H) is disclosed in U.S. Patent
Application Publication No. US2004/0009970, hereby incorporated by reference
herein in its entirety. DCDQ itself is not intended to be within the compounds of
Formula I disclosed herein.
In some embodiments, the invention provides hydroxy compounds of formula
I. Preferably, at least one of Z and R1 through R8 is hydroxy.
In some embodiments, the invention further provides hydroxy compounds of
formula I where X-Y is CR9HNR10. Some examples of such hydroxy compounds
include those where:
R and R10 are each H;
at least one of R7 and R8 is -OH;
R6 is -OH;
at least one of R3 and R4 is-OH; or
at least one of R1, R5, R8, R7, and Z is-OH.
In other embodiments, the invention provides hydroxy compounds of formula I
where X-Y is CR9HNR10 and R10 is acetyl. Some preferred examples of such
hydroxyl compounds include those where:
at least one of R7 and R8 is -OH;
In other embodiments, the invention provides hydroxy compounds of formula I
wherein X-Y is C=N. In some preferred embodiments, at least one of R1 through R6
is -OH. In other preferred embodiments, at least one of R2 through R4 is -OH.
In other embodiments, the invention provides glucuronyl compounds
according to formula I, wherein at least one of R1 through R6, R9, R10, and Z is
-C(0)-O-G,-O-G, or-G.
In some preferred embodiments, the invention provides glucuronyl
compounds where X-Y is CR9HNR10. In some preferred embodiments, R9 and R10
are H. In other preferred embodiments, at least one of Z, R3, and R4 is -O-G. In
other preferred embodiments, at least one of R1 through R6, R9, and Z is -O-G.
In still further embodiments, the invention provides glucuronyl compounds of
formula I where R2 along with R3 taken together form a double bond between the
carbons to which they are attached, and at least one of R3' and R4 is -O-G.
In other embodiments, the invention provides glucuronyl compounds of
formula I where R10 is -C(O)O-G or-G. In some embodiments, such compounds are
further provided where R4 and R4> together with the carbon to which they are attached
form C=O.
In some embodiments, the invention provides glucuronyl compounds where
X-Y is -CHR9NR10 where R10 is -C(O)-O-G.
In some preferred embodiments, the invention provides compounds of
formula I wherein Z, each Rn and Rn> is H, X-Y is -CHR9NR10. In some such
embodiments, R9 is H. In preferred embodiments, R9 is H and R10 is -C(O)-O-G.
In other embodiments, the invention provides glucuronyl compounds of
formula I, where R10 is acetyl. In a preferred embodiment, such derivatives are
further provided where at least one of R1 through R6, R9, and Z is -O-G. In still other
embodiments, at least one of R7 and R8 is -O-G.
In some embodiments, the invention provides sulfate compounds according
to formula I where at least one of R1 through R9, and Z is -OSO3H.
In some preferred embodiments, the invention provides such sulfate
compounds where X-Y is ~CHR9NR10. In some such embodiments, R9 and R10 each
are H. In some such embodiments, at least one of R1 through R6 is -OSO3H. In
further embodiments, at least one of R2 and R3 is -OSO3H. In some embodiments,
R3is-OS03H.
In some embodiments, the invention provides sulfate compounds of formula I,
where at least one of R9 and Z is -OSO3H.
In some embodiments, the invention provides sulfamate compounds
according to formula I. In some embodiments, the invention provides such sulfamate
compounds where X-Y is CR9HNR10, and R10 is -SO3H. In other embodiments, the
invention provides such sulfamate compounds where at least two of Rn and its
corresponding R"*1, where n = 1-5, form a double bond between the carbons to
which they are attached.
In some embodiments, the invention provides keto compounds according to
formula I, where Rn and its corresponding R"' taken together with the carbon to which
they are attached form C=O. In some preferred embodiments, n = 4. In further
preferred embodiments, X-Y is CR9HNR10 and preferably R10 is -G. In other
embodiments, R9 and R10 are H.
Other embodiments of keto compounds according to formula I provide
compounds where X-Y is C(O)NH,
In some embodiments, the invention provides imine compounds according to
formula I. In some embodiments, X-Y is CH=N. In some such embodiments, at least
one of R1 through R6 is -OH. In other such embodiments, at least one of R2 through
R4 is -OH. In still other such embodiments, the compound may be an N-oxide,
wherein the nitrogen between the carbons to which R8 and R7 are attached forms an
N-oxide.
In still further embodiments, the invention provides dehydro compounds of
formula I, containing one or more double bonds. In these embodiments, such
compounds are provided wherein at least one of Rn and its corresponding Rn+1,
where n = 1-5, together form a double bond between the carbons to which they are
attached and each Rn> and R(n+1)' is independently hydrogen, hydroxy, CH3C(O)-O,
-OSO3H, or-O-G. In some preferred embodiments, n = 2. In further preferred
embodiments, n=2, R2' = H, and R3' or R4 is -O-G. In still further embodiments, X-Y is
CHR9NR10, where R9 and R10 are preferably H.
In other embodiments, di-dehydro compounds of formula I are provided,
where for at least two Rn, each said Rn and its corresponding Rn+1, where n = 1-5,
together form a double bond between the carbons to which they are attached. In
some preferred embodiments, the invention further provides that X-Y = CHR9NR10.
(Figure Removed)

In further embodiments, R10 is H; and Z or R9 is -OSO3H. In still other embodiments,
X-Y = CHR9NR10 and R9 = R10 = H.
In some embodiments, the invention provides such di-dehydro compounds of
formula I where R10 is -SO3H, or acetyl.
In some aspects of the invention, the compounds of formula I are provided in
isolated form.
In other aspects of the inventions, the compounds of formula I are provided is
substantially pure form of at least 75% purity. In other aspects, the compounds are
at least 80% pure. In other aspects, the compounds are at least 85% pure. In other
aspects, the compounds are at least 90% pure. In other aspects, the compounds are
at least 95% pure.
Acetyl, as used herein, refers to CH3-C(=O)-.
Alkyl, as used herein, refers to an aliphatic hydrocarbon chain, e.g., of 1 to 6
carbon atoms, and includes, but is not limited to, straight and branched chains such
as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyt, sec-butyl, t-butyl, n-pentyl,
isopentyl, neo-pentyl, n-hexyl, and isohexyl. Lower alkyl refers to alkyl having 1 to 3
carbon atoms.
BOP refers to (Benzotriazol-1-yloxy)tris(dimethylamino)phosphonium
hexafluorophosphate.
Carbamoyl, as used herein, refers to the group, -C(=O)N<.
DCC refers to N.N'-Dicyclohexylcarbodiimide.
DIBAH and DIBAL refer, interchangeably, to diisobutylaluminum hydride.
DMAP refers to 4-dimethylaminopyridine.
DPPA refers to diphenylphosphoryl azide.
EDC refers to 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride.
Glucuronyl, as used herein, refers to the group:
HQ OH
Halogen (or halo) as used herein refers to chlorine, bromine, fluorine and
iodine. HDnig's Base is N.N-diisopropylethylamine, also indicated herein as £-Pr2NEt.
PyBOP refers to (Benzotriazol-l-yloxy)tripyrrolidinophosphonium
hexafluorophosphate.
The compounds of this invention contain asymmetric carbon atoms and thus
give rise to optical isomers and diastereoisomers. The present invention includes
such optical isomers and diastereoisomers; as well as the racemic and resolved,
enantiomerically pure R and S stereoisomers; as well as other mixtures of the R and
S stereoisomers and pharmaceutically acceptable salts thereof.
Where an enantiomer is preferred, it may, in some embodiments be provided
substantially free of the corresponding enantiomer. Thus, an enantiomer
substantially free of the corresponding enantiomer refers to a compound which is
isolated or separated via separation techniques or prepared free of the
corresponding enantiomer. "Substantially free," as used herein, means that the
compound is made up of a significantly greater proportion of one enantiomer. In
preferred embodiments, the compound is made up of at least about 90% by weight of
a preferred enantiomer. In other embodiments of the invention, the compound is
made up of at least about 99% by weight of a preferred enantiomer. Preferred
enantiomers may be isolated from racemic mixtures by any method known to those
skilled in the art, including high performance liquid chromatography (HPLC) and the
formation and crystallization of chira! salts or prepared by methods described herein.
See, for example, Jacques, et al., Enantiomers, Racemates and Resolutions (Wiley
Interscience, New York, 1981); Wilen, S.H., et al., Tetrahedron 33:2725 (1977); Eliel,
E.L. Stereochemistry of Carbon Compounds (McGraw-Hill, NY, 1962); Wilen, S.H.
Tables of Resolving Agents and Optical Resolutions p. 268 (E.L. Eliel, Ed., Univ. of
Notre Dame Press, Notre Dame, IN 1972).
One skilled in the art will also recognize that it is possible for tautomers to
exist of formula (I). The present invention includes all such tautomers even though
not shown in formula (I).
The compounds useful in the present invention also include pharmaceutically
acceptable salts of the compounds of formula (I). By "pharmaceutically acceptable
salt", it is meant any compound formed by the addition of a pharmaceutically
acceptable base and a compound of formula (I) to form the corresponding salt. By
the term "pharmaceutically acceptable" it is meant a substance that is acceptable for
use in pharmaceutical applications from a toxicological perspective and does not
adversely interact with the active ingredient. Pharmaceutically acceptable salts,
including mono- and bi-salts, include, but are not limited to, those derived from such
organic and inorganic acids such as, but not limited to, acetic, lactic, citric, cinnamic,
tartaric, succinic, fumaric, maleic, malonic, mandelic, malic, oxalic, propionic,
hydrochloric, hydrobromic, phosphoric, nitric, sulfuric, glycolic, pyruvic,
methanesulfonic, ethanesulfonic, toluenesulfonic, salicylic, benzole, and similarly
known acceptable acids.
Non-limiting, examples of compounds of Formula I include those identified
through the in vitro and in vivo studies detailed herein, and shown In the metabolic
pathways depicted in Figs. 1-4. Such examples include those shown below. Where
the attachment of a given substituents is described by a box, it is intended that the
indicated substituent can be attached to any one or more available carbon atoms
within the box.
(Figure Removed)

These proposed syntheses are exemplary only. Those of skill in the art will
recognize that other syntheses may be used to make the various compounds of the
invention. Additionally, those of skill in the art will recognize that an intermediate in
any the schemes described above may be a compound according to Formula I and
may be collected and purified, if necessary, without going to the next step. For
example, the nitrone above may be isolated and purified. Furthermore, those of skill
in the art will recognize that these syntheses may be modified to yield related
compounds which are described by Formula I, herein. These and other variations or
modifications of these methods, compounds, and intermediates are considered with
the scope and spirit of the invention disclosed herein.
METHODS OF TREATMENT
The binding affinity of DCDQ, and related compounds, is well-documented in
the related published applications WO03/091250 and US2004/0009970, each of
which is incorporated by reference. Accordingly, the metabolites, which form after
administration of DCDQ, can also be used similarly to DODQ in treating psychotic
and other disorders.
The compounds of this invention are agonists and partial agonists at the 2C
subtype of brain serotonin receptors and are thus of interest for the treatment of
mental disorders, including psychotic disorders such as schizophrenia including
paranoid type, disorganized type, catatonic type, and undifferentiated type,
schizophreniform disorder, schizoaffective disorder, delusional disorder, substanceinduced
psychotic disorder, and psychotic disorder not otherwise specified; L-DOPAinduced
psychosis; psychosis associated with Alzheimer's dementia; psychosis
associated with Parkinson's disease; psychosis associated with Lewy body disease;
bipolar disorders such as bipolar 1 disorder, bipolar II disorder, and cyclothymic
disorder; depressive disorders such as major depressive disorder, dysthymic
disorder, substance-induced mood disorder, and depressive disorder not otherwise
specified; mood episodes such as major depressive episode, manic episode, mixed
episode, and hypomanic episode; anxiety disorders such as panic attack,
agoraphobia, panic disorder, specific phobia, social phobia, obsessive compulsive
disorder, posttraumatic stress disorder, acute stress disorder, generalized anxiety
disorder, separation anxiety disorder, substance-induced anxiety disorder, and
anxiety disorder not otherwise specified; adjustment disorders such as adjustment
disorders with anxiety and/or depressed mood; intellectual deficit disorders such as
dementia, Alzheimer's disease, and memory deficit; eating disorders (e.g.,
hyperphagia, bulimia or anorexia nervosa) and combinations of these mental
disorders that may be present in a mammal. For example, mood disorders such as
depressive disorders or bipolar disorders often accompany psychotic disorders such
as schizophrenia. A more complete description of the aforementioned mental
disorders can be found in the Diagnostic and Statistical Manual of Mental Disorders,
4th edition, Washington, DC, American Psychiatric Association (1994).
The compounds of the present invention are also of interest for the treatment
of epilepsy; migraines; sexual dysfunction; sleep disorders; gastrointestinal disorders,
such as malfunction of gastrointestinal motiiity; and obesity, with its consequent
comorbidities including Type II diabetes, cardiovascular disease, hypertension,
hyperlipidemia, stroke, osteoarthritis, sleep apnea, gall bladder disease, gout, some
cancers, some infertility, and early mortality. The compounds of the present
invention can also be used to treat central nervous system deficiencies associated,
for example, with trauma, stroke, and spinal cord injuries. The compounds of the
present invention can therefore be used to improve or inhibit further degradation of
central nervous system activity during or following the malady or trauma in question.
Included in these improvements are maintenance or improvement in motor and
motility skills, control, coordination and strength.
Thus the present invention provides methods of treating each of the maladies
listed above in a mammal, preferably in a human, the methods comprising providing
a therapeutically effective amount of a compound of this inversion to the mammal in
need thereof. By "treating", as used herein, it is meant partially or completely
alleviating, inhibiting, preventing, ameliorating and/or relieving the disorder. For
example, "treating" as used herein includes partially or completely alleviating,
inhibiting or relieving the condition in question. "Mammals" as used herein refers to
warm blooded vertebrate animals, such as humans. "Provide", as used herein,
means either directly administering a compound or composition of the present
invention, or administering a derivative or analog which will form an equivalent
amount of the active compound or substance within the body.
PHARMACEUTICAL COMPOSITIONS
Also encompassed by the present invention are pharmaceutical compositions
for treating or controlling disease states or conditions of the central nervous system
comprising at least one compound of Formula I, mixtures thereof, and or
pharmaceutical salts thereof, and a pharmaceutically acceptable carrier therefore. -
Such compositions are prepared in accordance with acceptable pharmaceutical
procedures, such as described in Remingtons Pharmaceutical Sciences, 17th
edition, ed. Alfonoso R. Gennaro, Mack Publishing Company, Easton, PA (1985).
Pharmaceutically acceptable carriers are those that are compatible with the other
ingredients in the formulation and biologically acceptable.
The compounds of this invention may be administered orally or parenterally,
neat or in combination with conventional pharmaceutical carriers, the proportion of
which is determined by the solubility and chemical nature of the compound, chosen
route of administration and standard pharmacological practice. The pharmaceutical
earner may be solid or liquid.
Applicable solid carriers can include one or more substances which may also
act as flavoring agents, lubricants, solubilizers, suspending agents, fillers, glidants,
compression aids, binders or tablet-disintegrating agents or an encapsulating
material. In powders, the carrier is a finely divided solid which is in admixture with
the finely divided active ingredient. In tablets, the active ingredient is mixed with a
carrier having the necessary compression properties in suitable proportions and
compacted in the shape and size desired. The powders and tablets preferably
contain up to 99% of the active ingredient. Suitable solid carriers include, for
example, calcium phosphate, magnesium stearate, talc, sugars, lactose, dextrin,
starch, gelatin, cellulose, methyl cellulose, sodium carboxymethyl cellulose,
polyvinylpyrrolidine, low melting waxes and ion exchange resins.
Liquid carriers may be used in preparing solutions, suspensions, emulsions,
syrups and elixirs. The active ingredient of this invention can be dissolved or
suspended in a pharmaceutically acceptable liquid carrier such as water, an organic
solvent, a mixture of both or pharmaceutically acceptable oils or fat. The liquid
carrier can contain other suitable pharmaceutical additives such as solubilizers,
emulsifiers, buffers, preservatives, sweeteners, flavoring agents, suspending agents,
thickening agents, colors, viscosity regulators, stabilizers or osmo-regulators.
Suitable examples of liquid carriers for oral and parenteral administration include
water (particularly containing additives as above, e.g. cellulose derivatives, preferably
sodium carboxymethyl cellulose solution), alcohols (including monohydric alcohols
and polyhydric alcohols e.g. glycols) and their derivatives, and oils (e.g. fractionated
coconut oil and arachis oil). For parenteral administration the carrier can also be an
oily ester such as ethyl oleate and isopropyl myristate. Sterile liquid carriers are used
in sterile liquid form compositions for parenteral administration. The liquid carrier for
pressurized compositions can be halogenated hydrocarbon or other pharmaceutically
acceptable propellant.
Liquid pharmaceutical compositions which are sterile solutions or
suspensions can be administered by, for example, intramuscular, intraperitoneal or
subcutaneous injection. Sterile solutions can also be administered intravenously.
Oral administration may be either liquid or solid composition form.
The compounds of this invention may be administered rectally or vaginally in
the form of a conventional suppository. For administration by intranasal or
intrabronchial inhalation or insufflation, the compounds of this invention may be
formulated into an aqueous or partially aqueous solution, which can then be utilized
in the form of an aerosol. The compounds of this invention may also be administered
transdermally through the use of a transdermal patch containing the active
compound and a carrier that is inert to the active compound, is non toxic to the skin,
and allows delivery of the agent for systemic absorption into the blood stream via the
skin. The carrier may take any number of forms such as creams and ointments,
pastes, gels, and occlusive devices. The creams and ointments may be viscous
liquid or semisolid emulsions of either the oil-in-water or water-in-oil type. Pastes
comprised of absorptive powders dispersed in petroleum or hydrophilic petroleum
containing the active ingredient may also be suitable. A variety of occlusive devices
may be used to release the active ingredient into the blood stream such as a
semipermeable membrane covering a reservoir containing the active ingredient with
or without a carrier, or a matrix containing the active ingredient. Other occlusive
devices are known in the literature.
Preferably the pharmaceutical composition is in unit dosage form, e.g. as
tablets, capsules, powders, solutions, suspensions, emulsions, granules, or
suppositories. In such form, the composition is sub-divided in unit dose containing
appropriate quantities of the active ingredient; the unit dosage forms can be
packaged compositions, for example packeted powders, vials, ampoules, prefilled
syringes or sachets containing liquids. The unit dosage form can be, for example, a
capsule or tablet itself, or it can be the appropriate number of any such compositions
in package form.
The dosage requirements vary with the particular compositions employed, the
route of administration, the severity of the symptoms presented and the particular
subject being treated. Based on the results obtained in the standard
pharmacological test procedures, projected estimated daily dosages of active
compound would be approximately 0.02 ug/kg - approximately 4000 ug/kg, or up to
approximately 500mg/day. It is to be understood that these dosage ranges are
merely estimates and those of skill in the art will be able to ascertain appropriate
doses depending on many factors, including patient weight, severity of symptoms,
and other factors. Treatment will generally be initiated with small dosages less than
the optimum dose of the compound. Thereafter the dosage is increased until the
optimum effect under the circumstances is reached; precise dosages for oral,
parenteral, nasal, or intrabronchial administration will be determined by the
administering physician based on experience with the individual subject treated.
EXAMPLES
Metabolite Compounds
The metabolism of DCDQ was investigated in several in vitro and in vivo
models by using a radio-labeled version of DCDQ, [14C]DCDQ. The studies revealed
several metabolic pathways and several significant metabolites. These studies are'
explained in further detail in the Experimental section, below.
The metabolism of [14C]DCDQ was investigated by incubation with liver
microsomes from male and female CD-1 mice, Sprague Dawley rats, beagle dogs
and human liver microsomes pooled across sexes, and cryopreseived male human
hepatocytes. DCDQ was converted to oxidative metabolites, including M1, M2, M3,
M4, M5, and a carbamoyl glucuronide (M6) in microsomal incubations and human
hepatocytes.
The in vivo metabolism of [14C]DCDQ was further investigated in four male'
beagle dogs following a single administration of 14.1 to 16.7 mg/kg of [14C]DCDQ
hydrochloride in an enteric coated capsule. The major metabolites observed in
plasma included hydroxy DCDQ (M1, M2 and M3), an N-oxide DCDQ (M5), a keto
DCDQ (M7), a hydroxy DCDQ imine (M15), a hydroxy DCDQ glucuronide (M9) and
the carbamoyl glucuronide of DCDQ (M6). A sulfate conjugate of hydroxy DCDQ
(M16) and a diazepinyl DCDQ carboxylic acid (M17), which were not detected in
plasma, were observed in urine samples. Hydroxy DCDQ metabolites (M2, M3 and
M19), a keto DCDQ (M18) and the hydroxy DCDQ imine (M15) were detected in
fecal extracts. DCDQ was extensively metabolized in dogs, with the oxidative
metabolism as the major metabolic pathway, although formation of a DCDQ
carbamoyl glucuronide (M6) was also observed.
The in vivo metabolism of [14C]DCDQ was further studied in male and female
Sprague-Dawley rats after a single oral administration (5 mg/kg). Metabolites
detected in plasma included hydroxy DCDQ metabolites (M1, M2, M3, M4 and M10),
keto DCDQ (M7), and the phase II metabolites DCDQ sulfamate (M12), di-dehydro
DCDQ sulfamate (M14), hydroxy DCDQ sulfates (M8 and M13), hydroxy DCDQ
glucuronide (M9) and aoetylated hydroxy DCDQ (M11). DCDQ was extensively
metabolized in rats to predominantly oxidative metabolites,
Thus, metabolites of DCDQ are created through several metabolic pathways,
some of which are common across several species. Such metabolites can be useful
in treating disorders and diseases affected by the 5HT2C receptor and/or those that
can be treated by administration of DCDQ.
SYNTHESIS OF THE CARBAMOYL GLUCURONYL METABOLITE (M6)
Metabolite M6 can be obtained by coupling DCDQ with a glucuronyl carrier 6
in the presence of a coupling reagent and an amine in CH2CI2 to yield compound 7.
The product, compound 7 can be purified according to methods known in the art, and
preferably by column chromatography purification, preferably with EtOAc/heptane as
an eluent. The coupling reagent can be selected from any suitable coupling
reagent, including but not limited to BOP, DCC, and EDC. BOP is the preferred
coupling agent. Suitable amines include, but are not limited to Et3N, pyridine, and
Hilnig's base. HQnig's base is preferred. The glucuronyl carrier 6 can be prepared
by methods known to those of skill in the art. L1 is an aliphatic leaving group, such
as, but not limited to, Cf to Ca alkyl, methyl, ethyl, and propyl, preferably methyl. .
Each La is a leaving group which is independently selected from an acetyl group and
a benzyllic group. Acetyl groups are preferred. The glucuronyl carrier 6 is preferably
a secondary amine glucuronyl carbamate 6 such as those that can be designed on
the basis of the Scheeren's protocol discussed in Ruben G. G. Leeders, Hans W.
Scheeren, Tetrahedron Letters 2000, 41, 9173-9175.
Glucuronyl Carbamoyl Metabolite M6
HO
OH
M6 Metabolite
Compound 7 is then subjected to basic hydrolysis resulting in deprotection of all
leaving groups, L2, on 2,3,4-positipn of sugar moiety as well as L1 to yield the final
product M6 metabolite. Basic hydrolysis is carried out using base, such as NaOH,
LiOH, and KOH in CrC3 aliphatic alcohol. LiOH is the preferred base and MeOH is
the preferred alcohol. . Removal of organic solvents and lyophilization can be used
to yield crude product M6 in a quantitative yield. Purification of the crude M6 can then
be carried out by methods known to those of skill in the art.
Compound 6 can be prepared by deprotection of the allyl group in compound
5 catalyzed preferably by using Pd(PPh3)4, and morpholine as a nucleophile. Fresh
catalyst is preferred. Additionally N2 may optionally be bubbled through the reaction
solution before adding catalyst. In this way, the crude glucuronyl carrier 6 is obtained
in a quantitative yield without further purification.
Compound 5
(Figure Removed)

5 can be prepared in high yield in a one-pot reaction. Treatment of
compound 2 with one of DPPA, NaN3, or TMSN3 in the presence of EfeN in toluene in
situ produces an acyl azide 10, which is heated, preferably to 80 "C for 1.5 hour, to
yield isocyanate 3. The compound 3 need not be isolated and is subsequently
treated with a 1-hydroxyglucuronic ester 4, preferably at room temperature overnight
to obtain the title compound 5 (Scheme 3). Compound 4 can be prepared by
following the procedure described US6,380,166B1, which is hereby incorporated by
reference. 1H NMR at 30'C shows that all signals are double due to restricted
rotation around the Ar-Ar bond.
In compound 4, L1 is an aliphatic leaving group, such as, but not limited to, Ci
to Ce alkyl, methyl, ethyl, and propyl, preferably methyl. Each L2 is a leaving group
which is independently selected from an acetyl group and a benzyllic group. Acetyl
groups are preferred.
Compound 2
In order to prepare monoallyl ester 2, diphenic anhydride was chosen as a
starting material and treated with excess of allyl alcohol in the presence of catalyst
Sutiable catalysts include EfeN, HQnig's base, pyridine, amines, NaOH, LiOH, KPH,
and other inorganic bases. Quantitative yields for compound 2 can be achieved.
Compound 5
(Figure Removed)

Compound 5 can be prepared in high yield in a one-pot reaction. Treatment of
compound 2 with one of DPPA, NaN3, or TMSN3 in the presence of Et3N in toluene in
s/ft; produces an acyl azide 1U, which is heated, preferably to 80 'C for 1.5 hour, to
yield isocyanate 3. The compound 3 need not be isolated and is subsequently
treated with a 1-hydroxyglucuronic ester 4, preferably at room temperature overnight
to obtain the title compound 5 (Scheme 3). Compound 4 can be prepared by
following the procedure described US6,380,166B1, which is hereby incorporated by
reference. 'H NMR at 30'C shows that all signals are double due to restricted
rotation around the Ar-Ar bond.
In compound 4, L1 is an aliphatic leaving group, such as, but not limited to, Cf
to C6 alky), methyl, ethyl, and propyl, preferably methyl. Each L2 is a leaving group
which is independently selected from an acetyl group and a benzyllic group. Acetyl
groups are preferred.
EXEMPLARY SYNTHESIS OF THE CARBAMOYL GLUCURONYL METABOLITE
(M6)
An exemplary synthesis of DCDQ carbamoyl glucuronide metabolite (M6) is
shown in Scheme 1:
NMR spectra were recorded on a Varian Inova 300 at 300 MHz ('H and 13C) and
chemical shifts were identified in ppm relative to TMS internal standard. Analytical
and preparative TLCs were performed on Silica Gel 60 F-254 pre-coated plates
obtained from EM Science. Compounds were visualized using UV at 254 nm or 10%
aq. KMnO4 indicator. HPLC analysis was determined on a Waters Alliance 2695
HPLC instrument ^quipped with a PDA (Model 2996) UV detector. Mass spectra
were recorded on a Rnnigan mass spectrometer.
BIPHENYL-2,2'-DfCARBOXYLIC ACID 2'-ALLYL ESTER 2
To a 1-L flask was charged diphenic anhydride (40 g, 178 mmol), allyl alcohol
(300 mL) and DMAP (2.18 g, 17.8 mmol, 10 mol%). The reaction mixture was stirred
for 12 h. The excess of allyl alcohol was evaporated under reduced pressure at 40
°C. The residue was redissolved in EtOAc (400 mL) and washed with aq. NaHSO4
(0.5 N, 200 mL), brine (200 mL x 3) and water (200 mL x 3). The organic layer was
dried with anhydrous Na2S04, passed through a silica gel pad (500 g), washed the
pad with EtOAc (1 L), concentrated under reduced pressure to dryness. Traces of
allyl alcohol were removed by distillation with heptane to give the mono allyl ester 2
(50 g, 100%) as a colorless oil. 'H NMR (300 MHz, CDCI3): 8.03-7.99 (m, 2H), 7.56-
7.39 (m, 4H), 7,19-7.16 (m, 2H), 5.74-5.61 (m, 1H), 5.17-5.06 (m, 2H), 4.52-4.49 (m,
2H).
3,4,5-TRIACETOXY-6-(2'-ALLYLOXYCARBONYLBlPHENYL-2-
YLCARBAMOYLOXY)
TETRAHYDRO-PYRAN-2-CARBOXYLIC ACID METHYL ESTER 5
To a 500 mL-flask was charged biphenyl-2,2'-dicarboxy!ic acid 2'-allyl ester 2
(5.2 g, 18.4 mmol), toluene (100 mL), DPPA (4.8 ml, 22.1 mmol, 1.2 eq) and EfeN
(3.1 ml, 22.1 mmol, 1.2 eq) under nitrogen atmosphere. The reaction mixture was
stirred overnight at room termperature, then heated to 85 "C for 1.5 h to generate in
situ intermediate isocyanate 3. The mixture was cooled to room temperature. To this
mixture was added methyl 2,3,4-triacetyM-hydroxyglucuronic ester 4 (3.7 g, 11
mmol, 0.6 eq)'and stirred overnight The mixture was diluted with EtOAc (500 mL),
washed subsequently with aq. NaHSO4 (0.5 N, 200 mL), saturated NaHCO3 (200
mL), brine (200 mL x 2) and water (200 mL). The organic layer was dried over
anhydrous NaSO4 and concentrated under reduced pressure. The residue (11 g),
mixed with silica gel (22 g), was loaded on a column (4.5 x 50 cm) which was packed
with silica gel (500 g). The column was washed with EtOAc/heptane (2:8,6 L; 3:7,4
L; 4:6,4 L). Fractions (60 mL/fraction) were collected and solvent was evaporated to
give compound 5 (5.5 g, 82%). HPLC, RT=7.73 min, purity: 81.44%. 'HNMR (300
MHz, CDCIs), all signals are double due to restricted rotation around the Ar-Ar bond,
8.03-7.93 (m, 2H), 7.64-7.48 (m, 2H), 7.40-7.23 (m, 2H), 7.18-7.05 (m, 2H), 6.49,
6.42 (2s, 1H, NH), 5.74, 5.73 (2d, J = 8.1 Hz, 1H, p-anomer), 5.70-5.57 (m, 1H), 5.33-
temperature under nitrogen atmosphere to become a solution. To this solution was
added dropwise a solution of DCDQ (2.5 g, 9.6 mmot, 1.1 eq) and N,N-diisopropyl-Nethy!
amine (7.6 ml, 43.5 mmol, 5 eq) in CH2CI2 (200 ml) in 10 min. The reaction
mixture was stirred overnight and filtered through celite. The organic layer was
washed with water (200 ml), dried over MgS04 and evaporated. The residue was
purified by column chromatography (column: 4.5 x 50 cm> silica gel: 500 g, solvent:
EtOAc/heptane (2/8,4 L), (3/7, 8 L), 50 ml/fraction) to obtain compound 7 (4.0 g,
HPLC: 74%), further slurry in CH2CI2 to give compound 7 (3.52 g, 68.8%, HPLC:
96%). 1HNMR (300 MHz, DMSO-d6): 7.12-7.08 (m, 'H), 6.98-6.96 (m, 1H), 6.86-6.77
(m, 1H), 5.81,5,79 (2d, J = 8.1 Hz, 1H, j3-anomer), 5.10-4.90 (m, 2H), 4.63-4.36 (m,
2H), 4.17-4.12 (m, 1H), 3.88-3.68 (m, 1H), 3.64, 3.59 (2s, 3H), 3.40-3.21 (m, 1H),.
3.04-2.59 (m, 4H), 2.30-2.14 (m, 'H), 2.05-1.95 (3s, 9H), 1.70-1.20 (m, 5H). MS:
m/z589[M + H]+.
MS Metabolite of DCDQ
(Figure Removed)

A solution of compound 7 (5.0 g, 8.5 mmol) in THF (64 mL) was added MeOH
(319 mL) and H2O (70 mL). The solution was cooled to 0-5 °C (ice-water bath). And a
solution of LiOH»H2O (2.1 g, 51 mmol, 6 eq) in H2O (58 mL) [0.1 N
LiOH/MeOH/THF/H2O] was added dropwise in 20 min. The reaction mixture was
stirred at 0-5 CC for 2 hours under Nz atmosphere. Progress of the deprotection was
monitored on reversed-phase TLC (Si02-C18 MeCN/H20,3/7). The reaction mixture
was diluted with H2O (500 mL) and neutralized by adding HOAc (3.1 g, 51 mmol) at
20 °C. The solvent was concentrated under reduced pressure at 22 °C and the
resultant aqueous suspension was lyophilized to give crude M6 metabolite (6.2 g,
100%). Further purification of the crude compound (1.2 g) using Biotage silica gel
column chromatography (Horizon),2 CHCI3/MeOH/H2O as an eluent provided M6
(400 mg) with 95% purity (HPLC). 1HNMR (300 MHz, DMSO-d6, D2O exchange):
7.13-6.99 (m, 2H), 6.87-6.80 (m, 1H), 5.09 (d, J = 7.8 Hz, 1H, p-anomer), 4.77-4.58
(m, 1H), 4.19-4.12 (m, 1H), 3.93 (m, 1H), 3.40-2.87 (9m, 9H), 2.68-2.60 (m, 1H), 2.24-
1.99 (m, 3H), 1.63-1.20 (m, 4H); 13C (75 MHz, DMSO-d6): 173.3,173.1,154.6,
154.0,147.3,132.5,132.4,130.9,130.6,130.1,127.9,127.7,121.4,121.1, 96.9,
96.3, 77.1, 76.9, 75.3, 73.2, 72.9, 72.6, 56.9, 56.1, 55.6, 50.9, 50.4, 48.7, 41.7, 35.0,
34.9,32.5, 32.3, 29.8,24.1; LC/MS (ESI), m/z 449 [M+H]*.
REFERENCES
1. HPLC equipment: Waters 2690
Sample preparation: add 2-3 drops of the reaction mixture to 2 ml of acetonitrite,
shake well to a solution and subject to HPLC analysis.
HPLC conditions:
Column: Alltima CIB 3jim 7x53 mm
Column temperature: 25 °C
Mobile phases: Solvent A = 1900 mL H20,100 mL CH3CN, 1 mL H3PO4;
Solvent B = 1900 mL CH3CN, 100 mL H20,1 mL H3PO4
(Table Removed)
IN VITRO / IN VIVO METABOLITE STUDIES
DCDQ is a potent 5-HT2C agonist and is effective in several animal models
predictive of antipsychotic activity, with an atypical antipsychotic profile. The
behavioral profile of DCDQ in these models is consistent with atypical antipsychpticlike
activity with diminished extrapyramidal side-effect liability. The 5-HT2c agonist
DCDQ may also be effective in treating the mood disorders or the cognitive
impairments associated with schizophrenia.
Several metabolites of DCDQ were identified through in vivo and in vitro
models. Without being bound to the theory behind the pathways, FIGS. 1-4 show
proposed metabolic pathways leading to these compounds.
IN VITRO METABOLISM OF [14C]DCDQ IN LIVER MICROSOMES OF MICE, RATS,
DOGS AND HUMANS, AND IN CRYOPRESERVED HUMAN HEPATOCYTES
The metabolism of [14C]DCDQ was investigated by incubation with liver
microsomes from male and female CD-1 mice, Sprague Dawley rats, beagle dogs
and human liver microsomes pooled across sexes, and cryopreserved male human
hepatocytes. Using human liver microsomes, the Km values for the formation of the
major oxidative metabolite M1 and the carbamoyl glucuronide M6 were 10.8 and 56.1
H.M, respectively.
Species differences were observed in DCDQ metabolism. Oxidative
metabolism was the major metabolic pathway for DCDQ in hepatic microsomal
incubations. Several hydroxy metabolites (M1, M2, M3 and M4) of DCDQ were
detected with human liver microsomes in the presence of NADPH. Metabolite Ml
was not detected in other species. Metabolites M2 and M3 were also observed with
dog and rat. Metabolite M4 was also detected in rat, but not in mouse or dog.
Mouse appeared to have less extensive metabolism than other species, and M2 was
the only metabolite detected with mouse liver microsomes. An N-oxide of DCDQ
imine (MS) was detected with dog and human, but not with mouse or rat liver
microsomes. Formation of DCDQ imine (P3) and currently unidentified products P1
and P2 in liver microsomes from all species was not NADPH-dependent, and
requires further investigation. Sex differences were not observed in microsomal
incubations for mice, rats and dogs.
In the presence of UDPGA, the carbamoyl glucuronide of DCDQ (MS) was
detected with dog and human, but not with mouse or rat liver microsomes. While
formation of the hydroxy metabolites was the major metabolic pathway with human
liver microsomes in the presence of both NADPH and UDPGA, the carbamoyl
glucuronide was the major metabolite in human hepatocytes at 50 fiM DCDQ
concentration.
In summary, DCDQ was converted to oxidative metabolites and a carbamoyl
glucuronide in microsomal incubations and human hepatocytes.
INTRODUCTION
This study investigated the in vitro biotransformation of DCDQ in liver
microsomes and human hepatocytes. Cytochrome P450 and
UDP-glucuronosyltransferase dependent pathways were examined and DCDQ
metabolites were characterized by LC/MS.
MATERIALS AND METHODS
MATERIALS
hydrochloride (Lot L25073-42) was synthesized by the radiosynthesis
group of Wyeth Research (Pearl River, NY). The radiochemical purity of
t14C]DCDQ was 98.9% and the chemical purity was 99.9% by UV detection. The
specific activity of the [UC]DCDQ was 222.9 nCi/mg as a hydrochloride salt. The
chemical structure of [14C]DCDQ is shown with the position of the 14C label. The nonlabeled
DCDQ hydrochloride (Lot PB3312) with a chemical purity of 98.6% was
synthesized by Wyeth Research (Pearl River, NY). Unless otherwise indicated,
when referring to DCDQ or [14C]DCDQ, the hydrochloride salt is assumed.
DCDQ
C15H2N2
Monoisotopic MW of
unlabeled free base = 228.2
Cryopreserved human hepatocytes, hepatocyte suspension media and
hepatocyte culture media were obtained from In Vitro Technologies (Baltimore, MD).
The hepatocytes were from two male individuals (Lot 070, 57 year old and Lot DRL,
44 year old) with testosterone 6B-hydroxylase activity of 55 and 43 pmol/106
cells/mm, respectively, as determined by In Vitro Technologies. Liver mtcrosomes
listed in the following Table 2 from CD-1 mice, Sprague Dawley rats and beagle dogs
were also obtained from In Vitro Technologies.
(Table Removed)

Human liver microsomes from subjects 3, 6,15,17,18 and 19 were prepared
from livers received from I'AM (Exton, PA). These microsomes were prepared and
characterized by Dr. Andrew Parkinson and are described in Parkinson A.
Preparation and characterization of human liver microsomes. Wyeth-Ayerst
Research GTR-25617,1994, which is hereby incorporated by reference. Microsomal
preparations were stored at approximately -70°C in aliquots of 250-500 \tL until use.
The following Table lists the characteristics of the human liver microsomes used in
this study.
(Table Removed)

Mean value of pooled microsomes (N=6) 0.51
Ultima Gold, Ultima Flo, Permafluor E+-scinti!lation cocktails, and Carbo-Sorb
E carbon dioxide absorber were purchased from Perkin Elmer (Wellesley, MA). High
performance liquid chromatography (HPLC) grade water and acetonitrile were
obtained from EMD Chemicals (Gibbstown, NJ). Undine S'-diphosphoglucuronic acid
triammonium salt (UDPGA) and EDTA were obtained from Sigma Chemical Co. (St.
Louis, MO). Ammonium acetate and magnesium chloride were obtained from
Mallinckrodt Baker Inc. (Phillipsburg, NJ). All other reagents were analytical grade or
better.
METHODS
INCUBATION OF [UC]DCDQ WITH LIVER MICROSOMES OF MICE,
RATS, DOGS AND HUMANS
[14C]DCDQ was mixed with non-radiolabeled DCDQ (1:3 or 1:5) in the
incubations. Microsomal incubations consisted of [14C]DCDQ, magnesium chloride
(10 mM) and liver microsomes incubated in 0.5 mL of 0.1 M potassium phosphate
buffer, pH 7.4. [14C]DCDQ (20 \nL) in water was added to the incubation tubes
containing buffer, magnesium chloride solution and microsomes. After mixing, the
tubes were pre-incubated for 2 minutes in a shaking water bath at 37°C. The
reactions were initiated by the addition of UDPGA or the NADPH regenerating
system. UDPGA was added to incubations as a 50 aliquot of a 20 mM solution in
water, to give a final concentration of 2 mM. An NADPH regenerating system (30 ^L)
was added to incubations to evaluate CYP450-mediated metabolism. The NADPH
regenerating system consisted of glucose-6-phosphate (2 mg/mL), glucose-6-
phosphate dehydrogenase (0.8 units/mL) and NADP* (2 mg/mL). Control
incubations were conducted under the same conditions, but without the NADPH
generating system, UDPGA or microsomes. All incubations were performed in
duplicate. Incubations were stopped by the addition of 0.5 mL ice-cold methanol.
Samples were vortex-mixed. Denatured proteins were separated by centrifugation at
4300 rpm and 4°C for 10 minutes (Model T21 super centrifuge, Sorvall). The protein
pellets were extracted with 0.5 mL of methanol. The supernatant was combined for
each sample, mixed and evaporated to a volume of about 0.3 mL under a nitrogen
stream in a Zymark TurboVap LV evaporator (Caliper Life Science, Hopkinton, MA).
The concentrated sample was centrifuged and aliquots were radioassayed and
analyzed by HPLC. This method recovered an average of 92.1% of the radioactivity
from the reaction mixture.
Initial rate conditions were determined for DCDQ metabolism in incubations
with human liver microsomes in the presence of NADPH or UDPGA. Incubations for
the time course study contained 20 u.M of [14C]DCDQ and 0.5 mg/mL of microsomal
proteins, and were incubated at 37°C with mild shaking for 0,5,10, 20,30,40, 50
and 60 minutes. The protein dependence study was conducted with 20 u,M of
f14C]DCDQ incubated for 20 minutes with 0,0.1,0.25, 0.5, 0.75 and 1.0 mg/mL of
microsomal proteins.
The Km values were determined with 0.5 mg/mL of human liver microsomes
incubated with [14C]DCDQ for 20 minutes with the NADPH regenerating system or for
10 ,-ninutes with UDPGA. [14C]DCDQ concentrations used were 0.5,1,5,10, 25,50,
75and100nM.
To evaluate species differences in cytochrome P450- and UGT-mediated
metabolism, [14C]DCDQ was Incubated for 20 minutes with 0.5 mg/mL liver
microsomal proteins from mice, rats, dogs or humans in the presence of the NADPH
regenerating system or UDPGA. The assay conditions were the same as described
above, and DCDQ concentrations were 12 jJvl and 56 pM for cytochrome P450- and
UGT-mediated metabolism, respectively.
Samples were analyzed for metabolites by radioactivity flow detection and by
LC/MS.
PREPARATION OF HUMAN HEPATOCYTES
Vials containing cryopreserved human hepatocytes were thawed in a 37°C
water bath with gentle shaking until the ice was almost melted. The vials were
removed from the water bath and gentle shaking continued at room temperature for
30-60 seconds until completely thawed. The hepatocyte suspensions from each vial
were immediately transferred to pre-cooled 50 mL beakers on ice. To each beaker,
12 mL of ice-cotd hepatocyte suspension media was added dropwise over one
minute, with occasional, gentle shaking by hand to prevent the cells from settling.
The cell suspensions were transferred to a 15 mLtube and centrifuged at 100 g force
for 3 min at4°C (Model T21 super centrifuge, Sorvall). The supernatant was
discarded and the pellets were re-suspended in 4 mL of ice-cold hepatocyte culture
media. The cell suspensions contained approximately 3.1 x 106 viable
hepatocytes/mL The average viability was 76.0% as determined using Trypan Blue
exclusion and a hemacytometer.
INCUBATION OF [14C]DCDQ WITH HUMAN HEPATOCYTES
The cell suspensions were distributed into 12-well plates at 1.0 mL per well.
Incubations were performed using pooled hepatocytes from two donors. [1*C]DCDQ
in water was added to the hepatocyte suspension at a final concentration of 10 or
50 jiM. Incubations were carried out at 37°C for 4 hours in an incubator supplied
with 5% CO2. At the end of the incubation, the reaction was stopped by the addition
of 200 U.L cold methanol to each well. The content of each well was transferred to a
15 mL centrifuge tube and sonicated for 30 seconds. After vortex mixing with 6 mL
methanol and then centrifugation, the supernatant was transferred to a clean tube
and evaporated to about u.5 mL in a TurboVap evaporator: The residue was
analyzed by HPLC and LC/MS.
HPLC ANALYSIS
A Waters model 2690 HPLC system (Waters Corp., Milford, MA) with a builtin
autosampler was used for analysis. Separations were accomplished on a
Phenomenex Luna Ci8(2) column (2x150 mm, 5 nm) (Phenomenex, Torrance, CA)
coupled with a fitter (4x2 mm) cartridge. A variable wavelength UV detector set to
monitor 250 nm and Flo-One B Model A525 radioactivity flow detector (Perkin Elmer)
with a 250 jiL LQTR flow cell were used for data acquisition. The flow rate of Ultima
Flow M scintillation fluid was 1 mL/min, providing a mixing ratio of scintillation cocktail
to mobile phase of 5:1. The sample chamber in the autosampler was maintained at
4°C, while the column was at ambient temperature of about 20"C. The mobile phase
consisted of 10 mM ammonium acetate, pH 4.5 (A) and methanol (B) and was
delivered at 0.2 mL/min. The linear gradient conditions were as follows
(Table Removed)
:
LIQUID CHROMATOGRAPHY/MASS SPECTROMETRY
An Agilent Model 1100 HPLC system (Agilent Technologies, Palo Alto, CA)
including an autosampler and diode array UV detector was used for LC/MS analysis.
The UV detector was set to monitor 200 to 400 nm. For selected LC/MS analysis,
radiochromatograms were acquired using a p-Ram model 3 radioactivity flow
detector (IN/US Systems Inc., Tampa, FL) equipped with a solid scintillant flow cell.
Separations were accomplished on a Phenomenex Luna C18(2) column (2x150 mm,
5 nm) under the same conditions as described above.
The mass spectrometer used for metabolite characterization was a
Micromass Q-TOF-2 quadrupole time-of-flight hybrid mass spectrometer (Nature
Corp.). The mass spectrometer was equipped with an electrospray ionlzation (ESI)
Interface and operated in the positive ionfeation mode. Collision energy settings of 5
and 30 eV were used for full MS and MS/MS scans, respectively. Settings for the
mass spectrometer are listed below.
(Table Removed)
I
Flo-One analytical software (Perkin Elmer, version 3.6) was utilized to
integrate the radioactive peaks. The computer program Microsoft Excel® 97 was
used to calculate means and standard deviations and to perform the Student t-test.
Micromass Mass Lynx software (Waters, version 4.0) was used forcoflection and
-analysis of LC/MS dala.
RESULTS
DETERMINATION OF Km VALUES WITH HUMAN LIVER MICROSOMES
Initial rate conditions and Km values for metabolite formation from [14C]DCDQ
were determined for human liver microsomes. In the time-dependency studies,
NADPH-dependent formation of the major oxidative metabolites (M1, M2, M3 and
M4) was linear for 20 minutes and formation of the carbamoyl glucuronide (M6) was
linear for 10 minutes (data not shown). In the protein-dependency studies, oxidative
metabolism and carbamoyl glucuronide formation were linear up to 0.5 mg/mL
microsomal protein. The Km values for the formation of the major oxidative
metabolite M1 and the carbamoyl glucuronide M6 in human liver microsomes were
10.8 and 56.1 nM, respectively. The Km values for formation of metabolites M2, M3
and M4 in human liver microsomes ranged from 8.9 to 13.8 nM. The K™ value for
metabolite M5 formation in human liver microsomes was 36.2 \iM.
[14C]DCDQ METABOLISM BY LIVER MICROSOMES OF
MICE, RATS, DOGS, AND HUMANS
For species comparison in microsomal incubations, DCDQ concentrations for
P450- and UGT-mediated metabolism were 12 and 56 |iM, respectively, which were
about the Km values. In the presence of the NADPH regenerating system, four
hydroxy metabolites (M1, M2, M3 and M4) were detected with human microsomes.
Metabolite M1 was not detected in other species. Metabolites M2 and M3 were
observed with dog and rat Metabolite M4 was also detected in rat, but not in mouse
or dog. Mouse appeared to have less extensive metabolism than other species, and
M2 was the only metabolite detected with mouse liver microsomes. An N-oxide of
DCDQ Imine (M5) was detected with dog and human, but not mouse or rat. Three
other peaks (P1, P2 and a DCDQ imine P3) were also observed in microsomal
incubations. Formation of P1, P2 and P3 were not NADPH-dependent. Since these
products were not formed in the control incubations without microsomes (data not
shown), their formation may be catalyzed by non-P450 enzymes.
In the presence of UDPGA, formation of carbamoyl glucuronide of DCDQ
(M6) was detected with liver microsomes of dog and human, but not mouse or rat.
When DCDQ (20 yM) was incubated with human liver microsomes in the presence of
both NADPH and UDPGA, formation of the hydroxy metabolites was the major
metabolic pathway, and only minor amounts of the carbamoyl glucuronide were
detected. Gender differences were not observed in microsomal incubations for
mouse, rat and dog.
[14C]DCDQ METABOLISM BY HUMAN HEPATOCYTES
When DCDQ was incubated with human hepatocytes, the carbamoyl
glucuronide (M6) was the most prominent metabolite at 50 nM DCDQ concentration.
Oxidative metabolites were also observed at 50 \M DCDQ concentration, although
less abundant relative to the carbamoyl glucuronide. Incubations containing 10 yM
DCDQ with human hepatocytes produced oxidative metabolites at levels
approaching those of the carbamoyl glucuronide. In addition to the metabolites
formed in human microsomal incubations, another metabolite (M7) was detected.
The DCDQ imine (P3), which was formed in microsomes, was also observed in the
hepatocyte incubations.
METABOLITE.CHARACTERIZATION BY LC/MS ANALYSIS
Mass spectra were obtained by LC/MS and LC/MS/MS analysis for DCDQ
and its metabolites. Structural characterization of these compounds is summarized
(Table Removed)

The mass spectral characterization of DCDQ and its metabolites identified in
each of the studies are discussed further below.
DISCUSSION
Species differences were observed in DCDQ metabolism. Oxidative
metabolism was the major metabolic pathway for DCDQ in hepatic microsomal
incubations. Several hydroxy metabolites (M1, M2, M3 and M4) of DCDQ were
detected with human liver microsomes in the presence of NADPH (Figure 1).
Metabolites M2 and M3 were also observed with dog and rat liver microsomes.
Mouse had less extensive metabolism than other species, and M2 was the only
metabolite detected with mouse liver microsomes. An N-oxide of DCDQ imine (M5)
was detected in microsomal incubations for. dog and human, but not mouse or rat
liver microsomes. In the presence of UDPGA, the carbamoyi glucuronide of DCDQ
(M6) was detected with dog and human, but not mouse or rat. While formation of the
hydroxy metabolites was the major metabolic pathway with human liver microsomes
in the presence of both NADPH and UDPGA, the carbamoyi glucuronide M6 was the
major metabolite in human hepatocytes at 50 uM DCDQ concentration. Enzyme
systems other than P450 may also contribute to DCDQ metabolism by formation of a
DCDQ imine (P3) and other products (P1 and P2). Formation of products P1, P2
and P3 was not NADPH-dependent, and requires further investigation since they
were generally present in all incubations with liver microsomes and hepatocytes.
Sex differences were not observed for mice, rats or dogs in microsomal incubations.
In summary, DCDQ was converted to oxidative metabolites and a carbamoyi
glucuronide in microsomal incubations and human hepatocytes.
IN VIVO METABOLISM OF [14C]DCDQ IN MALE AND FEMALE SPRAGUEDAWLEY
RATS FOLLOWING A SINGLE (5 MG/KG) ORAL GAVAGE
ADMINISTRATION
SYNOPSIS
The present study investigated the in vivo metabolism of [14C]DCDQ in male
and female Sprague-Dawley rats after a single oral administration (5 mg/kg). Blood,
plasma and brain were collected at 2,4,8 and 24 hour post-dose from male rats and
at 2 and 8 hour post-dose from female rats. Urine and feces were collected from
male rats at intervals of 0-8 and 8-24 hours post-dose.
In mate rats, plasma radioactivity concentrations were 632 ± 144,659 ± 16.5,,
465 ± 43.1, and 46.9 ± 8.30 ng equivalents/mL at 2,4, 8 and ?4 hour post-dose,
respectively. For female rats, the mean plasma radioactivity concentration of 658 ±
189 ng equivalents/mL at 2 hour post-dose was similar to male rats, but the average
radioactivity concentration of 338 ± 60.7 ng equivalents/mL at 8 hour post-dose was
lower than male rats. The average blood-to-plasma ratio was about 1.1 between 2
and 8 hour post-dose, indicating limited partitioning of DCDQ and its metabolites into
blood cells.
DCDQ represented an average of 13% to 20% of plasma radioactivity
between 2 and 8 hour post-dose. The 24 hour plasma samples were not analyzed
for profiles due to low radioactivity concentrations. Changes in metabolite profiles
were not apparent over time. Metabolites detected in plasma included hydroxy
DCDQ metabolites (M1, M2, M3, M4 and M10), keto DCDQ (M7), and the phase II
metabolites DCDQ sulfamate (M12), di-dehydro DCDQ sulfamate (M14), hydroxy
DCDQ sulfates (M8 and M13), hydroxy DCDQ glucuronide (M9) and acetylated
hydroxy DCDQ (M11). Plasma metabolite profiles exhibited sex-related differences.
While the hydroxy OCDQ metabolites (M1, M2 and M3), the keto DCDQ (M7) and the
hydroxy DCDQ glucuronide (M9) were the major metabolites in male rat plasma, the
hydroxy DCDQ metabolite (M3), the hydroxy DCDQ sulfate (M8), the hydroxy DCDQ
glucuronide (M9) and DCDQ sulfamate (M12) were the major metabolites in female
rats. The primary sex difference was in the formation of sulfates or sulfamates.
Urinary excretion was a major route of elimination of orally administered
DCDQ and accounted for 66.7% of the dose. The major metabolites observed in
plasma samples were also detected in urine, where DCDQ accounted for less than
1% of the dose. The hydroxy metabolites (M1 and M3), the keto DCDQ (M7) and the
glucuronide (M9) were the major metabolites in urine. An average of 21.1% of the
dosed radioactivity was recovered infeces. Metabolites M3, M8, M9, M10, M11 and
only trace amounts of DCDQ were detected in male rat feces.
Radioactivity in brain tissue was significantly higher than in plasma at 2,4 and
8 hour post-dose. Brain radioactivity concentrations were 5.12 ± 1.28,4.94 ± 0.44,
3.25 ± 0.99 and 0.037 ± 0.002 ng equivalents/g tissue at 2,4, 8 and 24 hour postdose
for male rats, respectively, while concentrations were 6.38 ± 2.22 and 2.85 ±
0.68 ng equivalents/g tissue at 2 and 8 hour post-dose for female rats, respectively.
The average brain-to-plasma radioactivity ratios between 2 and 8 hour post-dose
ranged from 6.9 to 9.6, indicating significant uptake by brain tissue. By 24 hour postdose,
the average brain-to-plasma radioactivity ratio decreased to 0.8. DCDQ
accounted for an average of greater than 90% of brain radioactivity for male and
female rats between 2 and 8 hour post-dose. Based on the radioactivity
concentrations and chromatographic distribution of brain radioactivity, it was
estimated that the average brain-to-plasma DCDQ ratios ranged from 49.9 to 56.1.
There were no significant gender differences or changes over time between 2 and 8
hour post-dose. Only minor amounts of metabolites M1, M3, M7, M10 and M11 were
detected in male or female rat brain. These data indicated that DCDQ readily
crossed the blood brain barrier, while uptake of metabolites into brain tissue was
limited. The brain-to-plasma radioactivity ratios also suggested that clearance from
brain occurred rapidly after 8 hour post-dose, since the ratios decreased from 6.9 to
0.8 by 24 hour post-dose.
In summary, DCDQ was extensively metabolized in rats to predominantly
oxidative metabolites. Plasma profiles for male and female rats differed in sulfate
and sulfamate conjugates of DCDQ and its oxidative metabolites. DCDQ was the
predominant drug related component in brain while only minor amounts of
metabolites were observed, and gender difference was not apparent. DCDQ readily
crossed the blood brain barrier while uptake of metabolites was limited to minor
amounts of oxidative metabolites.
INTRODUCTION ,
A previous mass balance study showed that urine was the major route of
excretion in rats, with an average of 64.3% of the dosed radioactivity recovered in
urine. An in vitro study with liver microsomes showed that oxidative metabolism was
the major metabolic pathway for DCDQ in rats. (Iwasaki K, Shiraga T, Tada K, Noda
K, Noguchi H. Age- and sex-related changes in amine sulphoconjugation in
Sprague-Dawley strain rats. Comparison with phenol and alcohol
sulphoconjugations. Xenobiotica. 1986;16:717-723.) The present study
investigated the metabolism of [14C]DCDQ in rats following a single 5 mg/kg oral
dose.
MATERIALS AND METHODS
MATERIALS
[14C]DCDQ hydrochloride was synthesized by the radiosynthesis group of
Wyeth Research (Pearl River, NY) as described in the in vitro study discussed
above. Ultima Gold, Ultima Flo, Permafluor E+-scintillation cocktails, and Carbo-
Sorb E carbon dioxide absorber were purchased from Perkin Elmer (Wellesley, MA).
Polysorbate 80 was obtained from Mallinckrodt Baker (Phillipsburg, NJ) and
methylcellulose was from Sigma-Aldrich (Milwaukee, Wl). Solvents used for
extraction and for chromatographic analysis were HPLC or ACS reagent grade from
EMD Chemicals (Gibbstown, NJ).
METHODS
DRUG ADMINISTRATION AND SPECIMEN COLLECTION
Dose preparation, animal dosing, and specimen collection were performed at
Wyeth Research, Collegeville, PA. The dose vehicle contained 2% (w/w) Tween 80
and 0.5% methylcellulose in water. On the day of dosing, [14C]DCDQ (12.2 mg) and
non-labeled DCDQ (36.5 mg) were dissolved in the vehicle to a final concentration of
approximately 2 mg/mL.
Male rats weighing from 318 to 345 grams and female rats weighing from 227
to 255 grams at the time of dosing were purchased from Charles River Laboratories,
Wilmington, MA. Non-fasted rats were given a single 5 mg/kg (~300 n-Ci/kg) dose of
DCDQ at a volume of 2.5 mL/kg via intragastric gavage. Animals were provided
Purina rat chow and water ad libitum, and were kept individually in metabolism
cages. Male rats were sacrificed at 2,4, 8 and 24 hour after dose administration.
Female rats were sacrificed at 2 and 8 hour after dose administration.
At sacrifice, blood samples were collected by cardiac puncture into tubes
containing EDTA as the anticoagulant and placing them on ice. Aliquots of 50 jiL
were removed for combustion and determination of radioactivity content. Plasma
was immediately obtained from the remaining blood by centrifugation at 4°C. Brains
were excised after perfusion with 50 ml of chilled sterile saline. Urine samples were
collected on dry ice at intervals of 0-8 and 8-24 hour post-dosing. Feces were
collected at intervals of 0-8 and 8-24 hr post-dosing at room temperature and were
homogenized as described previously. The biological specimens and aliquots of the
dosing solution at pre- and post-dose were stored at approximately -70°C until
analyzed.
RADIOACTIVITY DETERMINATIONS
Plasma (20 jiL) and urine (50 pi.) aliquots were analyzed for radioactivity
concentrations. Radioactivity determinations of dose, plasma and urine were made
with a Tri-Carb Model 3100 TR/LL liquid scintillation counter (LSC) (Perkin Elmer)
using 10 ml of Ultima Gold as the scintillation fluid.
Brain and fecal samples were weighed and homogenized in water at volumeto-
weight ratios of about 1:1 and 5:1, respectively. Blood aliquots (50 piL), brain
homogenates (0.1 gram) and fecal homogenates (0.2 gram) were placed on
Combusto-cones with Combusto-pads and combusted. A model 307 Tri-Carb
Sample Oxidizer, equipped with an Oximate-80 Robotic Automatic Sampler (Perkin
Elmer), was used for combustion. The liberated 14CO2 was trapped with Carbo-Sorb
E carbon dioxide absorber, mixed with PermaFluor® E+ liquid scintillation cocktail,
and counted in a Tri-Carb Model 3100 TR/LL liquid scintillation counter (Perkin
Elmer). The oxidation efficiency of the oxidizer was 98.2%.
A Flo-One p Model A525 radioactivity detector (Perkin Elmer) with a 250 \d.
LQTR flow cell was used for in-line radioactivity detection for HPLC. The flow rate of
Ultima Flow M scintillation fluid was 1 mL/min, providing a mixing ratio of scintillation
cocktail to mobile phase of 5:1. The limits of detection were approximately 1 ng.
equivalent/g for brain, 2 ng equivalents/ml for plasma, 5 ng equivalents/g for feces
and 10 ng equivalents/ml for urine.
DOSE ANALYSIS
Aliquots of the pre- and post-dose solutions were diluted with 25% methanoi
in water and analyzed for radioactivity concentrations as described above.
Approximately 100,000 DPM in 10 jiL of the diluted solution was analyzed by HPLC
for radibchemical purity and chemical purity. To determine the specific radioactivity
of the dose suspension, non-radiolabeled DCDQ was dissolved in methanoi, diluted
with 25% methanoi In water, and concurrently analyzed by HPLC to generate a
standard curve. Aliquots (10 pL) of the diluted dose solution were injected onto the
HPLC column and fractions were collected at 1 minute intervals after UV detection.
Radioactivity in each fraction was determined. Fractions were also collected from a
blank injection to obtain the background ievel of radioactivity.
PLASMA METABOLITE PROFILES
Plasma samples were analyzed for metabolite profiles by HPLC. Aliquots of
1.5 mL plasma were mixed with 3.0 mL methanoi, placed on ice for about
10 minutes, and then centrifuged. The supernatant was transferred to a clean tube.
The protein pellets were extracted once with 3.0 mL methanoi. The supematants
from precipitation and extraction of each sample were pooled, mixed, and evaporated
at 22"C under nitrogen in a Zymark TurboVap LV (Caliper Life Sciences,
Hopkinton, MA) to about 0.3 mL. The concentrated extract was centrifuged, the
supernatant volume measured and extraction efficiency was determined by analyzing
duplicate 10 uL aliquots for radioactivity. An aliquot of the supernatant (50-200 pL)
was analyzed by HPLC with radioactivity flow detection. Plasma extracts were also
analyzed by LC/MS.
ANALYSIS OF FECES AND URINE
Fecal homogenates were analyzed for metabolite profiles. Aliquots of 1 gram
of fecal homogenates were mixed with 2 mL methanoi, placed on ice for about
10 minutes and centrifuged. The supernatant was transferred to a clean tube. The
residue was extracted three times with 2 mL of a watermethanol (3:7) mixture. The
supernatants of each sample were combined, evaporated to about 1 mL, and
centrifuged. Extraction efficiency was determined by analyzing aliquots of 10 /iL of
the supernatant for radioactivity. An aliquot (50-200 nL) of the supernatant was
analyzed by HPLC with radioactivity flow detection for profiling. Samples were also
analyzed by LC/MS to characterize the radioactive peaks.
Urine was analyzed for radioactivity concentration as and analyzed for
metabolite profiles by direct injection onto the HPLC column. LC/MS analyses for
metabolite identification were also earned out with urine samples.
METABOLITE PROFILES IN BRAIN
Brain homogenates were analyzed for metabolite profiles. Aliquots of 1 gram
of brain homogenates were mixed with an equal volume of methanol, placed on ice
for about 10 minutes and centrifuged. The supernatant was transferred to a clean
tube. The residue was extracted three times with 1 mL methanol. The supernatants
of each sample were combined, evaporated to about 0.5 mL, and centrifuged.
Extraction efficiency was determined by analyzing aliquots of 10 nL of the
supernatant for radioactivity. An aliquot (100-200 \iL) of the supernatant was
analyzed by HPLC with radioactivity flow detection for profiling. Samples were also
analyzed by LC/MS to characterize the radioactive peaks.
• HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
A Waters model 2690 HPLC system (Waters Corp., Milford, MA) with a builtin
autosampler was used for analysis. Separations were accomplished on a
Phenomenex Luna C18(2) column (150 x 2.0 mm, 5\m) (Phenomenex, Torrance,
CA). The sample chamber of the autosampler was maintained at 4"C, while the
column was at ambient temperature of about 20°C. A variable wavelength UV
detector set to monitor 250 nm and a Flo-One p Model A525 radioactivity detector
described above were used for data acquisition. The HPLC mobile phase consisted
of 10 mM ammonium acetate, pH 4.5 (A) and methanol (B), and was delivered at
0.2 mL/min. Chromatographic condition A was used for dose analysis, while
condition B was used for analysis of urine and plasma, brain and fecal extracts.
(Table Removed)

LC/MS ANALYSES
An Agilent Model! 100 HPLC system (Agilent Technologies, Wilmington, DE)
including an autosampler and diode array UV detector was used for LC/MS analysis
of plasma and urine samples. The UV detector was set to monitor 200 to 400 ntn.
For selected LC/MS analyses, radiochromatograms were acquired using a p-Ram
model 3 radioactivity flow detector (IN/US Systems Inc., Tampa, FL) equipped with a
solid scintillant flow cell. Fecal samples were also analyzed using a Waters Alliance
model 2690 HPLC system. It was equipped with a built-in autosampler and a model
996 diode array UV detector set to 210-350 nm. The HPLC flow was split between a
Radiomatic model 150TR flow scintillation analyzer (Perkin Elmer) and the mass
spectrometer. Other HPLC conditions were the same as condition B described
above.
The mass spectrometer used for metabolite characterization for plasma and
urine was a Micromass Q-TOF-2 quadrupole time-of-flight hybrid mass spectrometer
(Waters). The mass spectrometer was equipped with an electrospray ionization
(ESI) interface and operated in the positive ionization mode. Collision energy
settings of 5 and 30 eV were used for full MS and MS/MS scans, respectively.
Settings for the mass spectrometer are listed below.
(Table Removed)

DATA ANALYSIS AND STATISTICAL EVALUATION
Flo-One analytical software (Packard, version 3.6) was utilized to integrate
the radioactive peaks. The computer program Microsoft Excel® 97 was used to
calculate means and standard deviations and to perform the student t-test.
Micromass MassLynx software (Waters, version 4.0) was used for collection and
analysis of LC/MS data.
RESULTS
DOSE ANALYSIS
The radiochemical purity and estimated chemical purity (by ultraviolet
detection) of (14C]DCDQ in the dose solution were 99.0 ± 0.3% and 99.6 ± 0.1 %,
respectively. The pre- and post-dose aliquots had the same purity. The specific
activity of [1*C]DCDQ in the dosing solution was 48.2 u.Ci/mg as the hydrochloride
salt The average drug concentration was 2.48 mg/mL as the hydrochloride salt or
2.14 mg/mL as the free base. The actual dose of DCDQ administered ranged from
5.2 to 5.4 mg/kg as the free base, or 6.1 to 6.3 mg/kg as the hydrochloride salt.
PLASMA RADIOACTIVITY CONCENTRATIONS AND METABOLITE PROFILES
The concentrations of radioactivity in blood and plasma after a single oral
dose of [14C]DCDQ are summarized in Table 11.
(Table Removed)

Significantly lower than male at 8 hour, p<0.05
In male rats, the average plasma radioactivity concentrations were 632,659,
465 and 46.9 ng equivalents/mL at 2,4, 8 and 24 hour post-dose, respectively. In
female rats, the average plasma radioactivity concentration of 658 ng equivalents/mL
at 2 hour was similar to male rats, but the average plasma concentration of 338 ng
equivalents/mL at 8 hour post-dose was significantly tewer than in male rats. Blood
samples had slightly higher radioactivity concentrations than plasma at all time
points. The average blood-to-plasma radioactivity ratios ranged from about 1.1 for
male and female rats at 2,4 and 8 hour post-dose to about 1.5 for male rats at
24 hour post-dose, indicating limited partitioning of DCDQ or its metabolites into
blood cells (Tabfe 12).
(Table Removed)

Plasma extracts contained an average of 82 to 96% of total plasma
radioactivity for the 2,4 and 8 hour samples. Metabolite profiles were not obtained
from the 24 hour plasma samples due to low radioactivity concentrations. DCDQ
was extensively metabolized in rats. The parent drug represented an average of 13
to 20% of total radioactivity in plasma extracts with no apparent differences between
males and females or over time (Tables 13 and 14). Several hydroxy DCDQ
metabolites (M1, M2, M3, M4 and M10) and keto DCDQ (M7) were detected in
plasma (Figure 1). Phase II metabolites observed in plasma included DCDQ
sulfamate (M12, major in female plasma only), di-dehydro DCDQ sulfamate (M14,
major in female plasma only), hydroxy DCDQ sulfates (M8 and M13), hydroxy DCDQ
glucuronide (M9) and acetylated hydroxy DCDQ (M11) (Figure 1). Percent
distribution of plasma radioactivity did not change significantly over time, except for
metabolite MS, which was markedly lower at 8 hour post-dose. Metabolites M1, M2,
M3, M7 and M9 were the major metabolites in male rats, while M3, M8, M9 and M12
were the major metabolites in female rats, indicating sex differences in metabolite
profiles (Tables 13 and 14). A number of relatively minor metabolites detected in
plasma extracts were not characterized, although when combined represented
19-38% of the plasma radioactivity. Plasma concentrations of the individual
metabolites based on their percent distribution are presented in Table 4. DCDQ
concentrations generally equaled or exceeded the concentrations of each individual
metabolite in male and female rat plasma. In male rats, metabolites M1, M3+M9 and
M7 exhibited the highest concentrations while in female rats, metabolites M3+M9 and
M8 were the more prominent metabolites.
(Table Removed)

Concentrations were estimated based on the total plasma c:
radioactivity concentrations (Table 14) and the percent distribution d:
of plasma radioactivity (Table 13). e:
Standard deviation (n=3)
BQL, Below quantitation limit (2 ng equivalents/mL for plasma)
Significantly different from male, p<0.01
Significantly different from male, p<0.05
URINARY EXCRETION AND METABOLITE PROFILES
Urine was a major route of excretion, with 66.7 ± 5.0% of the radioactive dose
recovered in urine samples in the first 24 hours post-dose, with 32.5% in the 0-8 hour
period and 34.2% in the 8-24 hour period. Most of the major plasma metabolites were
also detected in urine (Table 15). The major metabolites in urine from male rats
included hydroxy DCDQ metabolites (M1, M2, M3 and M4), keto DCDQ (M7) and
hydroxy DCDQ glucuronide (M9) (Table 15). The individual metabolites in the 0-24 hour
urine represented about 2 to 16% of the administered dose (Table 16), while DCDQ
represented less than 1 % of the dose. The distribution of metabolites was similar for the
0-8 hour and 8-24 hour collections.
(Table Removed)

a: Standard deviation (n=3)
FFCAL EXCRETION AND METABOLITE PROFILES
Fecal elimination accounted for 21.1 ±2.1% of the dosed radioactivity recovered
in the first 24 hours post-dosing for male rats. Extraction efficiency for the 8-24 hour
fecal samples was 64.3%, while an average of 89.5% of the radioactivity was extracted
from incubations of [14C]DCDQ in control fecal homogenate. Hydroxy DCDQ
metabolites (M3 and M4), the hydroxy DCDQ sulfate (M8), the hydroxy DCDQ
glucuronide (M9) and the acetylated hydroxy DCDQ (M11) were the major metabolites in
the 8-24 hour fecal extracts, with only trace amounts of parent drug detected. Metabolite
profiles were not obtained from the 0-8 hour fecal samples because of low radioactivity
(less than 0.1% of dosed radioactivity). Incubation of [14C]DCDQ in fecal homogenate at
37°C for 24 hours showed no detectable degradation.
RADIOACTIVITY CONTENT AND METABOLITE PROFILES IN BRAIN
An average of 84.5% of the radioactivity in brain tissue was extracted. Brain
radioactivity concentrations were higher than plasma through 8 hours post-dose, and
DCDQ was the predominant drug-related component in rat brain. DCDQ accounted for
an average of greater than 90% of the radioactivity in brain extracts for male rats at 2,4
and 8 hour post-dose, and greater than 94% at 2 and 8 hour post-dose for female rats
The average radioactivity concentrations in male and female rat brain were
similar and only decreased slightly from 2 hour (5.1 and 6.4 jag equivalents/g for male
and female, respectively) to 8 hour (3.2 and 2.8 ug equivalents/g for male and female
rats, respectively). By 24 hour, the brain concentration, at an average of 0.04 pg
equivalents/g for male rats, was lower than in plasma. The average brain-to-plasma
radioactivity ratios between 2 and 8 hour post-dosing were 6.9 to 8.2 for male rats and
8.7 to 9.6 for female rats, and decreased to 0.8 at 24 hour for male rats. There were no
significant differences in brain radioactivity content or brain-to-plasma radioactivity ratios
between male and female rats. The brain-to-plasma DCDQ ratios were much higher
than the radioactivity ratios (Table 17). The average brain-to-plasma DCDQ ratio was
between 49.9 and 56.1 independent of time or sex. Only minor amounts of metabolites
M7, M10 and M11 were detected in male and female rat brain, and each metabolite
represented an average of less than 4.5% of brain radioactivity. Two additional minor
metabolites (M1 and M3) were observed in male rat brain. By 8 hour post-dose, most
metabolites were not detectable and only DCDQ was observed.
(Table Removed)

Time Concentration of Radioactivity % DCDQ of Brain
Brain/Plasma Ratio
(hr) (jig equivalents/g) Radioactivity
8 2.85 ± 0.68 2J38 ± 0.66 94.1 ±0.7 8.69 ± 2.86 56.1 ± 17.8
a: Data are presented as mean ± S.D., N=3
b: DCDQ concentrations were estimated on the total radioactivity concentrations in
brain and percent distribution of brain radioactivity,
c: Not available, concentration below level for profiling
METABOLITE CHARACTERIZATION BY LC/MS ANALYSES
Mass spectra were obtained by LC/MS and LC/MS/MS analysis for DCDQ and
its metabolites. Structural characterization of these compounds is summarized in
mass spectral characterization of DCDQ and its metabolites are
discussed below with the characterization from the other studies described herein.
(Table Removed)

a: LC/MS retention times were normalized to LC/MS data file GU_071 B03_0003, and
GU_081303_0002.
b: P=plasma; U=urine; B=brain; F=feces. Fecal metabolites were detected by selective reaction
Lmonitoring.
DISCUSSION
DCDQ was extensively metabolized in rats following a single oral 5 mg/kg
administration and oxidative metabolism was the major metabolic pathway. DCDQ
represented an average of 13% to 20% of plasma radioactivity between 2 and 8 hour
post-dose and less than 2% of total urinary radioactivity at 0-8 and 8-24 hour post-dose.
Metabolites observed in plasma included hydroxy DCDQ metabolites (M1, M2, M3, M4
and M10), keto DCDQ (M7), and phase II metabolites such as DCDQ sulfamate (M12),
di-dehydro DCDQ sulfamate (M14), hydroxy DCDQ sulfates (M8 and M13), hydroxy
DCDQ glucuronide (M9) and acetylated hydroxy DCDQ (M11) (Figure 1). Percent
distribution of radioactivity in plasma did not change significantly over time, except for
metabolite M8, which was significantly lower at 8 hour than 2 and 4 hour post-dose.
Plasma metabolite profiles exhibited differences in male and female rats. While the
hydroxy DCDQ metabolites (M1, M2 and M3), the keto DCDQ (M7) and the hydroxy
DCDQ glucuronide (M9) were the major metabolites in male rat plasma, the hydroxy
DCDQ metabolite (M3), the hydroxy DCDQ sulfate (MS), the hydroxy DCDQ glucuronide
(M9) and DCDQ sulfamate (M12) were the major metabolites in female rats. The
primary sex difference was in the formation of sulfates or sulfamates. These sex
differences were predictable since sulfotransferase activity toward alcohol and alicyclic
amines has been reported to be markedly higher in female rats than in male rats.
(Naritomi Y, Niwa T, Shiraga T, Iwasaki K, Noda K. Isolation and characterization of an
alicyclic amine N-sulfotransferase from female rat liver. Biological & Pharmaceutical
Bulletin. 1994;7:1008-1011.)
Most of the major plasma metabolites were also detected in urine. Similar
profiles were obtained for the 0-8 hour and the 8-24 hour urine samples. The major
metabolites in urine from male rats included hydroxy DCDQ metabolites (M1, M2, M3
and M4), keto DCDQ (M7) and hydroxy DCDQ glucuronide (M9). Each individual
metabolite in the 0-24 hour urine represented about 2 to 16% of the administered dose,
while DCDQ represented less than 1% of the dose. In the 8-24 hour fecal samples, the
hydroxy DCDQ metabolites (M3 and M4), the hydroxy DCDQ sulfate (M8), the hydroxy
DCDQ glucuronide (M9) and the acetylated hydroxy DCDQ (M11) were the major
metabolites observed, with only trace amounts of parent drug detected.
Radioactivity in brain tissue was significantly higher than in plasma at 2, 4 and 8
hour post-dose. DCDQ accounted for an average of greater than 90% of brain .
radioactivity for male and female rats. The average brain-to-plasma radioactivity ratios
between 2 and 8 hour post-dose ranged from 6.9 to 9.6, indicating uptake by brain
tissue. By 24 hour post-dose, the average brain-to-plasma radioactivity ratio decreased
to 0.8. Therewere no significant differences in brain radioactivity content or brain-toplasma
radioactivity ratios between male and female rats. The average brain-to-plasma
DCDQ ratios ranged from 49.9 to 56.1, with no sex differences or changes overtime
between 2 and 8 hour post-dose. Minor amounts of metabolites M7, M10 and M11 were
detected in male and female rat brain. These data indicated that DCDQ readily crossed
the blood brain barrier, while uptake of metabolites into brain tissue was limited. The
brain-to-plasma radioactivity ratios also suggested that clearance from brain occurred
rapidly after 8 hour post-dose, since the ratios decreased from 6.9 to 0.8 by 24 hour
post-dose. While partitioning of radioactivity into brain was apparent, partitioning into
blood cells was limited with blood-to-plasma ratios of only about 1.1 between 2 and 8
hour post-dose.
Metabolism of DCDQ appeared more extensive in the present study compared
with a previous in vitro metabolism study with rat liver microsomes. Only three oxidative
metabolites (M2, M3 and M4) were observed with rat liver microsomes and sex
differences were not observed. However, sex differences in formation of sulfates and
sulfamates, which were observed in rat, were not investigated in any in vitro system. In
addition to the metabolites M2, M3 and M4 detected with rat liver microsomes, other
oxidative metabolites (M1, M7 and M10) and several phase II metabolites (M8, M11,
M12, M13 and M14) were also observed in rats (Figure 1).
In summary, DCDQ was extensively metabolized in rats to predominantly
oxidative metabolites. Plasma profiles for male and female rats differed in sulfate and
sulfamate conjugates of DCDQ and some oxidative metabolites. DCDQ was the
predominant drug related component in brain while only minor amounts of metabolites
were observed, and sex differences were not apparent. DCDQ readily crossed the
blood brain barrier while uptake of metabolites was limited to minor amounts of oxidative
metabolites.
IN VIVO METABOLISM OF [14C]DCDQ IN MALE DOGS FOLLOWING A SINGLE
15 MG/KG ORAL CAPSULE ADMINISTRATION
SYNOPSIS
The present study investigated metabolism of [14C]DCDQ in four male beagle
dogs following a single administration of 14.1 to 16.7 m'g/kg of [14C]DCDQ hydrochloride
in an enteric coated capsule. Ptasma samples were collected at 2,4, 8, 24 and 48 hour
post-dose. Feces and urine were collected at intervals of 0-8, 8-24 and 24-48 hour postdose.
Samples were analyzed for radioactivity content and metabolite profiles.
Plasma concentrations of radioactivity were 422 ± 573, 564 ± 748, 528 ± 566,
1340 ± 508 and 507 ± 135 ng equivalents/ml at 2,4, 8,24 and 48 hour post-dose,
respectively. Large individual variations were observed in plasma radioactivity
concentrations, ranging from 4 to 1640 ng equivalents/ml at 2,4 and 8 hour post-dose.
The highest plasma radioactivity concentrations occurred at 24 hour except dog 2,
where concentrations were the highest at 4 hour post-dose. The data are consistent
with variations in excretion of radioactivity observed in the first 24 hours post-dose. The
variability may be associated with slow and prolonged absorption of DCDQ in some'
dogs, and the enteric-coated capsules. The average blood-to-plasma radioactivity ratio
for dog was approximately 0.72.
DCDQ was extensively metabolized in dogs. Oxidative metabolism was the
major metabolic pathway, while formation of a DCDQ carbamoyl glucuronide was also
observed. DCDQ represented 1.9% to 21% of plasma radioactivity at 2 and 4 hour, less
than 3% at 8 and 24 hour, and was not detected at 48 hour post-dose. DCDQ
accounted for an average of less than 11% of urinary radioactivity at all time periods. In
fecal extracts, 54% to 97% of the radioactivity was attributed to the parent drug. The
major metabolites observed in the 2 and 4 hour plasma included hydrcxy DCDQ (M1,
M2 and M3), an N-oxide DCDQ (M5), a keto DCDQ (M7), a hydroxy DCDQ imtne (M15),
a hydroxy DCDQ giucuronide (M9) and the carbomoyl glucuronide of DCDQ (M6)
(Figure 1). Metabolites M3 and M9 accounted for the majority of plasma radioactivity at
8, 24 and 48 hour post-dose. Metabolites M2, M3, M5 and M6 were also observed in
the in vitro incubation of DCDQ with dog liver microsomes in the presence of NADPH.
Metabolites observed in dog plasma were also detected in dog urine except for the
metabolite M7. A sulfate conjugate of hydroxy DCDQ (M16) and a diazepinyl DCDQ
carboxylic acid (M17), which were not detected in plasma, were observed in urine
samples. Hydroxy DCDQ metabolites (M2, M3 and M19), a keto DCDQ (M18) and the
hydroxy DCDQ imine (M15) were detected in fecal extracts. Extensive metabolism and
prolonged oral absorption of DCDQ probably accounted for the relatively low oral
bioavailability of approximately 25.4% in dogs.
Metabolism of DCDQ in dog exhibited some differences from rats. Some
different oxidative metabolites were observed in rats and dogs. Oxidative metabolites
M15, M16, M17, M18 and M19 were not observed in rats, while a hydroxy metabolite
M4, which was observed in rats, was not detected in dogs. More phase II metabolites
were observed in rats than in dogs. The sulfates M8 and M13,'and sulfamates M12 and
M14 were observed in rats, but not in dogs. The sulfate M16 was observed in dogs, but
not in rats. The carbamoyl glucuronide of DCDQ, which was detected in dog plasma
and urine, was not observed in rat plasma or urine.
In summary, DCDQ was extensively metabolized in dogs, with the oxidative
metabolism as the major metabolic pathway, although formation of a DCDQ carbamoyl
glucuronide was also observed.
INTRODUCTION
Mass balance studies showed that an average of 64.3% of the oral dose was
excreted in rat urine, while 32.7% of the dose was recovered in dog urine following
administration of an enteric-coated capsule. When incubated with dog liver microsomes
in the presence of NADPH and UDPGA, [14C]DCDQ was converted to several oxidative
metabolites and a carbamoyl glucuronide. A previous metabolism study rats showed
that DCDQ was extensively metabolized and oxidative metabolism was the major
metabolic pathway in rats, The present study investigated metabolism of [14C]DCDQ
following a single oral capsule administration to dogs.
MATERIALS AND METHODS
MATERIALS
[14C]DCDQ hydrochloride was synthesized by the radiosynthesis group of Wyeth
Research (Pearl River, NY) as described above in the in vivo studies. Ultima Gold,
Ultima Flo, Permafluor E+-scintillation cocktails, and Carbo-Sorb E carbon dioxide
absorber were purchased from Perkin Elmer (Wellesley, MA). EDTA was obtained from
Sigma-Aldrich (Milwaukee, Wl). Solvents used for extraction and for chromatographic
analysis were HPLC or ACS reagent grade from EMD Chemicals (Gibbstown, NJ).
METHODS
CAPSULE PREPARATION AND ANALYSIS
About 11 mg of [14C]DCDQ hydrochloride and 940 mg of non-labeled DCDQ
hydrochloride were dissolved in methanol and then evaporated under a nitrogen stream
to dryness. Capsules (#2) were filled with accurate amounts (126.7-138.1 mg) of the
mixed drug substance according to animal weights. The filled gelatin capsules were
then enteric-coated manually.
The drug substance in an extra capsule was analyzed for radiochemical purity
and specific activity. An aliquot of the drug substance was dissolved in DMSO, diluted in
water, and analyzed by HPLC with radioactivity flow detection and UV detection at 250
nm. To determine the specific activity, non-labeled DCDQ solutions at five different
concentrations were prepared by diluting a stock solution in methanol, and analyzed by
HPLC to generate a standard curve. The UV peak of [' 'C]DCDQ was integrated to
calculate the amount of DCDQ against the standard curve. Fractions around the
[14C]DCDQ peak were collected at 1 minute intervals after UV detection. Radioactivity in
each fraction was determined by liquid scintillation counting (LSC). Fractions were also
collected from a blank injection to obtain the background level of radioactivity.
DRUG ADMINISTRATION AND SPECIMEN COLLECTION
Four male beagle dogs, weighing from 7.6 to 9.8 kg at the time of dosing, were
from an in-house colony. Each dog was given one enteric-coated capsule containing
[14C]DCDQ as the hydrochloride salt. Animals were fed two hours prior to dosing and
provided Purina dog chow and water ad libitum, and were housed individually in
metabolic cages.
Blood samples were collected from the jugular vein at 2,4, 8, 24 and 48 hour
after dose administration into tubes containing potassium EDTA as the anticoagulant
and then placed on ice. Aliquots of 50 ^L were removed for combustion and
determination of radioactivity content. Plasma was immediately obtained from the
remaining blood by centrifugation at 4°C. Urine samples were collected into tubes on
dry ice at intervals of 0-8, 8-24 and 24-48 hour post-dose. Fecal samples were collected
at intervals of 0-8, 8-24 and 24-48 hour post-dose at room temperature, and were.
homogenized. The biological specimens were stored at approximately -70°C until
analysis.
RADIOACTIVITY DETERMINATIONS
Aliquots of 50 \iL of plasma and 100-200 pL of urine were analyzed for
radioactivity concentrations. Radioactivity determinations of dose, plasma, and urine
were made with a Tri-Carb Model 3100 TRILL LSC using 5-10 mL of Ultima Gold as the
scintillation fluid.
Feces were weighed and homogenized in water at a volume-to-weight ratio of
about 5:1. Aliquots of blood (200 pL) and fecal homogenates (0.25-0.53 gram) were
placed on Combusto-cones with Combusto-pads and combusted. A model 3u7 Tri-Carb
sample oxidizer, equipped with an Oximate-80 robotic automatic sampler (Perkirt Elmer),
was used for combustion of blood and fecal samples. The liberated 14CO2 was trapped
with Carbo-Sorb E carbon dioxide absorber, mixed with PermaFluor® E+ liquid
scintillation cocktail, and counted on a Tri-Carb Model 3100 TRILL liquid scintillation
counter (Perkin Elmer). The efficiency of combustion was 98.9%.
For plasma profiles, a TopCount NXT radiometric microplate reader (Perkin
Elmer) was used to analyze the radioactivity to collected HPLC fractions. The limit of
detection by TopCount was about 1 ng equivalent/mL. A Flo-One p Model A525
radioactivity detector (Perkin Elmer) with a 250 pi. LQTR flow cell was used to acquire
data for urine and fecal samples. The flow rate of Ultima Flow M scintillation fluid was
1 mL/min, providing a mixing ratio of scintillation cocktail to mobile phase of 5:1. The
limits of detection by Flo-One detector were about 200 ng equivalents/ml for urine and
12 ng equivalents/g for feces.
PLASMA METABOLITE PROFILES
Plasma samples were analyzed for metabolite profiles by HPLC. Aliquots of
plasma were mixed with two volumes of cold methanol containing 0.1% trifluoroacetic
acid (TFA), placed on ice for about 2 minutes and then centrifuged. The supernatant
fluid was transferred to a clean tube and evaporated at 22°C under nitrogen in a Zymark
TurboVap LV (Caliper Life Sciences, Hopkinton, MA) to a volume of about 0.3 mL The
residue was centrifuged, the supernatant volume measured and extraction efficiency
determined by analysis of duplicate 20 pL aliquots for radioactivity. A 200 pL aliquot of
the supernatant was injected onto the HPLC column and the effluent was collected at
20 second intervals into 96-well Lumaplates (Perkin Elmer). The plates were dried
overnight in an oven at 40°C and analyzed by a TopCount. Plasma extracts were also
analyzed by LC/MS.
ANALYSIS OF FECES AND URINE
Fecal homogenates were analyzed for metabolite profiles. Aliquots of 1 gram of
fecal homogenate were mixed with 2 mL methanol, placed on ice for about 10 minutes
and centrifuged. The supernatant was transferred to a clean tube. The residue was
extracted three times with 2 mL of a watenmethanol (3:7) mixture. The supernatants
from each sample were combined, evaporated to about 1 mL, and centrifuged.
Extraction efficiency was determined by analyzing aliquots of 10 p,L of the supernatant
for radioactivity. An aliquot (50-200 u.L) of the supernatant was analyzed by HPLC with
radioactivity flow detection for metabolite profiles. Samples were also analyzed by
LC/MS to characterize the radioactive peaks.
Urine was analyzed for radioactivity concentration and analyzed by HPLC with
radioactivity flow detection for metabolite profiles by direct injection to the HPLC column.
LC/MS analyses for metabolite identification were also carried out with urine samples.
HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
A Waters model 2690 HPLC system (Waters Corp., Milford, MA) with a built-in
autosampler was used for analysis. Separations were accomplished on a Phenomenex
Luna Ci8(2) column (150 x 2.0 mm, 5 pm) (Phenomenex, Torrance, CA). The sample
chamber of the autosampler was maintained at 4°C, while the column was at ambient
temperature of about 20°C. A variable wavelength UV detector set to monitor 250 nm
and a Flo-One p Model A525 radioactivity detector were used for data acquisition. The
HPLC mobile phase consisted of 10 mM ammonium acetate, pH 4.5 (A) and acetonitrile
(B), and was delivered at 0.2 mL/min. Chromatographic condition A was used for dose
analysis, while condition B was used for analysis of urine and plasma, brain and fecal
extracts.
(Table Removed)

Agilent Model 1100 HPLC system (Agilent Technologies, Palo Alto, CA)
including an autosampler and diode array UV detector was used for LC/MS analysis.
The UV detector was set to monitor 200 to 400 nm. For selected LC/MS analysis,
radiochromatograms were acquired using a p-Ram model 3 radioactivity flow detector
(IN/US Systems Inc., Tampa, FL) equipped with a solid scintillant flow cell. LC
conditions were the same as the condition B described above.
The mass spectrometer used for metabolite characterization was a Micromass
Q-TOF-2 quadrupole time-of-flight hybrid mass spectrometer (Waters). The mass
spectrometer was equipped with an electrospray ionization (ESI) interface and operated
in the positive ionization mode. Collision energy settings of 5 and 30 eV were used for
full MS and MS/MS scans, respectively. Settings for the mass spectrometer are listed
below.
(Table Removed)

DATA ANALYSIS AND STATISTICAL EVALUATION
Flo-One analytical software (Perkin Elmer, version 3.6) was utilized to integrate
the radioactive peaks. DataFlo Software Utility (Perkin Elmer, beta version 0.55) was
used to convert ASCII files from the TopCount NXT microplate counter into CR format
for processing in Flo-One Analysis software. The computer program Microsoft Excel®
97 was used to calculate means and standard deviations and to perform the student
test. Micromass MassLynx software (Waters, version 4.0) was used for collection and
analysis of LC/MS data.
RESULTS
ANALYSIS OF CAPSULE CONTENT
The [14C]DCDQ loaded in capsules had an average radiochemical purity of about
98.9% and a chemical purity (by ultraviolet detection) of greater than 99%. The specific
activity of [14CJDCDQ in the capsules was 2.18 jiCi/mg as the hydrochloride salt. The
actual DCDQ dose administered ranged from 12.2 to 14.4 mg/kg as the free base.
Plasma Radioactivity Concentrations and Metabolite Profiles
The concentrations of radioactivity in blood and plasma after a single capsule
dose of [14C]DCDQ are summarized in Table 21.
(Table Removed)

a: Dog number
The average plasma radioactivity concentrations ranged from 423 ng
equivalents/mL at 2 hour to 1340 ng equivalents/mL at 24 hour post-dose. The highest
radioactivity concentration generally occurred at 24 hour post-dose except for dog 2,
where concentrations were the highest at 4 hour post-dose. Large individual variations
were observed in plasma radioactivity concentrations, ranging from 4 to 1640 ng
equivalents/mL at 2,4 and 8 hour post-dose. The data are in agreement with the large
variations in excretion of radioactivity observed in the first 24 hours post-dose. These
variations may be attributed to slow and prolonged absorption of DCDQ in some dogs.
Blood radioactivity concentrations were lower than plasma radioactivity levels, and the
average blood-to-plasma radioactivity ratios ranged between 0.68 and 0.79 (Table 22).
Partitioning of DCDQ and its metabolites into blood cells was limited based on these
ratios.
(Table Removed)

than 3% of plasma radioactivity at 8 and 24 and was not detectable at 48 hour post-dose
(Tables 23 and 24). The major metabolites observed in the 2 and 4 hour plasma
included hydroxy DCDQ metabolites (M2 and M3), an N-oxide DCDQ (M5), a keto
DCDQ (M7), an imine of hydroxy DCDQ (M15), a glucuronide of hydroxy DCDQ (M9)
and a carbamoyl glucuronide of DCDQ (M6). Similar profiles were obtained for the 8, 24
and 48 plasma samples, although the majority of radioactivity at these later timfe points
was attributed to the hydroxy metabolite M3 and the glucuronide M9, which were not
chromatographically separated. A number of relatively minor metabolites accounted for
6.2% to 42% of plasma radioactivity in the 2 and 4 hour samples. These metabolites
were not characterized due to low concentrations.
(Table Removed)

a: Profiles for the 2 and 4 hour samples for dog 3 and 4, and the 8, 24 and 48 hour
samples for dog 4 were not obtained.
b: Includes non-characterized metabolites
c: Not detected
(Table Removed)

a: Data for the 2 and 4 hour samples for dog 3 and 4, and the 8,24 and 48 hour
samples for dog 4 were not obtained due to low concentrations of circulating
radioactivity; concentrations were estimated based on the total plasma
radioactivity concentrations (Table 21) and the chromatographic distribution of the
radioactivity (Table 23).
b: Below quantisation limit (1 ng equivalent/mL for plasma).
URINARY METABOLITE PROFILES
Urine was a major route of elimination of DCDQ in dog, although fecal excretion
was greater than urinary excretion. Numerous metabolites were detected in urine.
DCDQ represented an average of less than 11 % of the urinary radioactivity for all time
points (Table 25). The major metabolites included hydroxy DCDQ metabolites (M2 and
M3), an N-oxide DCDQ (M5), an imine of hydroxy DCDQ (M15), a hydroxy DCDQ
sulfate (M16), a diazepinyl DCDQ carboxylic acid (M17), a hydroxy DCDQ glucuronide
(Table Removed)

Chromatographic Distribution (Percentage) Of Radioactivity In Dog Urine Following Administration Of An Enteric-
Coated Capsule Containing [14C]DCDQa
Time Dog
(hr) No. M1 M2 M3+M9 M5 M6 M7 M15 M16 M17 DCDQ Others
C
~a: The 0-8 hour samples for dogs 2,3 and 4, and the 0-24 hour ^c? It includes a number of non-characterized metabolites
sample for dog 4 did not have enough radioactivity for profiling. d: Not available
b: ND, not detected
FECAL METABOLITE PROFILES
An average of 70.2% of the fecal radioactivity was extracted, while an average of
88.2% of the radioactivity was extracted from incubations of [14C]DCDQ in blank fecal
homogenate. In fecal extracts, DCDQ was major radioactive component, representing
54.4% to 96.7% of the total radioactivity. The metabolites detected in feces included
hydroxy DCDQ (M2, M3 and M19), a keto DCDQ (M18) and an uncharacterized peak
(M20). The most abundant metabolite M18 represented up to 16.4% of the total
radioactivity in fecal extracts. The glucuronide of hydroxy DCDQ (M9) and the
carbamoyl glucuronide of DCDQ (M6) were not detected in feces. Incubation of
[14C]DCDQ in fecal homogenate at 37°C for 24 hours showed no obvious degradation
(data not shown).
METABOLITE CHARACTERIZATION BY LC/MS ANALYSES
Mass spectra were obtained by LC/MS and LC/MS/MS analysis for DCDQ and
its metabolites. Structural characterization of these compounds is summarized in
a: LC/MS retention times were normalized to LC/MS data file GU_072303_0004,
(Table Removed)

GU_072403_0004, and GU_081403_0005
b: Matrix where metabolites were detected and characterized by LC/MS, P=plasma;
U=urine; B=brain; F=feces
DISCUSSION
Large individual variations were observed in plasma radioactivity concentrations,
ranging from 4 to 1640 ng equivalents/mL at 2, 4 and 8 hour post-dose. The data are
consistent with the variations in excretion of radioactivity observed in the first 24 hours
post-dose. Urinary excretion varied from 0 to 25% while fecal excretion ranged from 0 to
23% of the dosed radioactivity in the first 24 hours post-dose. The highest plasma
radioactivity concentrations occurred at 24 hour except dog 2, where concentration were
the highest at 4 hour post-dose. The variability may be associated with slow and
prolonged absorption of DCDQ in some dogs, and possibly the enteric-coated capsules.
The average blood-to-plasma radioactivity ratio for dog was approximately 0.72
compared with about 1.1 for rat between 2 and 8 hour post-dose, indicating less uptake
of DCDQ and its metabolites into blood cells of dog than of rat.
DCDQ was extensively metabolized in dogs as seen in rats, following
administration of an enteric-coated capsule containing [14C]DCDQ (Figure 1). Oxidative
metabolism was the major metabolic pathway, while formation of a DCDQ carbamoyl
glucurohide, which was not observed in rats, was also observed. DCDQ represented
1.9% to 21 % of plasma radioactivity at 2 and 4 hour, less than 3% at 8 and 24 hour, and
was not detected at 48 hour post-dose. DCDQ accounted for an average of less than
11% of urinary radioactivity at all time points. In fecal extracts, 54.4% to 96.7% of the
radioactivity was attributed to the parent drug. Plasma metabolites at 2 and 4 hour postdose
included hydroxy DCDu (M1, M2 and M3), an N-oxide DCDQ (MS), a keto DCDQ
(M7), a hydroxy DCDQ imtne (M15), a hydroxy DCDQ glucuronide (M9) and the
carbomoyl glucuronide of DCDQ (M6). The majority of radioactivity at 8, 24 and 48 hour
post-dose was attributed to the hydroxy metabolite M3 and the glucuronide M9, which
were not chromatographically separated. Metabolites M2, M3, M5 and M6 were also
observed in tha in vitro incubation of DCDQ with dog liver microsomes in the presence of
NADPH. Metabolites observed in dog plasma were also detected in dog urine except for
the metabolite M7. A sulrate conjugate of hydroxy DGDQ (M16) and a diazepinyl DCDQ
carboxylic acid (M17), which were not detected in plasma, were observed in urine
samples. Hydroxy DCDQ metabolites (M2, M3 and M19), a keto DCDQ (M18) and a
hydroxy DCDQ imine were detected in fecal extracts. Formation of metabolite M6 may
be underestimated due to possible hydrolysis in the Gl tract. Extensive metabolism and
prolonged oral absorption of DCDQ probably accounted for the relatively low oral
bioavailability of approximately 25.4% in dogs.
Metabolism of DCDQ in dog exhibited some differences from rats (Figure 1).
Some different oxidative metabolites were observed in rats and dogs. Oxidative
metabolites M15, M16, M17, M18 and M19 were not observed in rats, while a hydroxy
metabolite M4, which was observed in rats, was not detected in dogs. More phase II
metabolites were observed in rats than in dogs. The sulfates M8 and M13, and
sulfamates M12 and M14 were observed in rats, but not in dogs. The sulfate M16 was
*•
observed in dogs, but not in rats. The carbamoyl glucuronide of DCDQ, which was
detected in dog plasma and urine, was not observed in rat plasma or urine.
In summary, DCDQ was extensively metabolized in dogs, with the oxidative
metabolism as the major metabolic pathway, although formation of a DCDQ carbamoyl
glucuronide was also observed.
METABOLITE CHARACTERIZATION BY LC/MS ANALYSES
Mass spectra were obtained by LC/MS and LC/MS/MS analysis for DCDQ and
its metabolites identified in the studies above. The mass spectral characterization of
DCDQ and its metabolites, from each of the studies, are discussed below. .
DCDQ
The mass spectra! characteristics of DCDQ standard were examined for
comparison with the metabolites. In the LC/MS spectrum of DCDQ, a prbtonated
molecular ion, [M+H]*, was observed at m/z 229. The product ions of m/z 229 mass
spectrum of DCDQ obtained from collision-induced dissociation (CID), and the proposed
fragmentation scheme indicated loss of methyleneamine, ethylideneamine, and
ethylidene-methyl-amine from the molecular ion generated the product ions at m/z 200,
186, and 171, respectively. Loss of the propene group from the molecular ion generated
the fragment at m/z 187 and further loss of methyleneamine and ethylideneamine
generated the fragments ions at m/z 158 and 144. Loss of the cyclopentylmethyleneamine
group generated the fragment ion at m/z 132.
METABOLITE M1: FROM IN VITRO, AND IN VIVO RAT AND DOG STUDIES
The IM+H]+ for M1 was observed at m/z 245. The product ions of m/z 245 mass
spectrum of M1 and the proposed fragmentation scheme indicated an increase of 16 Da,
suggesting monohydroxylation. Loss of propene from the molecular ion generated the
fragment at m/z 203, which was 16 Da higher than the corresponding ion at m/z 187 for
DCDQ. The fragment ions at m/z 171 and 186 were the same as in the product ion
spectrum of DCDQ, indicating that the hydroxylation occurred in the diazepane portion of
the molecule as shown. Therefore, M1 was proposed to be hydroxy DCDQ.
METABOLITE M2: FROM FROM IN VITRO, AND IN VIVO RAT
AND DOG STUDIES
The [M+Hf for M2 was observed at m/z 245. The product ions of m/z 245 mass
spectrum of M2 and the proposed fragmentation scheme indicated an increase of 16 Da,
suggesting monohydroxylation. Loss of propene from the molecular ion generated the
fragment at m/z 203, which was 16 Da higher than the corresponding ion at m/z 187 for
DCDQ. This indicated that the cyclopentane ring was not the site of biotransformation.
The fragment ion at m/z 132 was the same for DCDQ indicating that the diazepane
portion was not the site of biotransformation. The fragment ions at m/z 169 and 184
wc.i« 2 Da less than the corresponding ions for DCDQ at m/z 171 snd 186, respectively,
indicating loss of H2O from the pyridine ring as a result of hydroxylation. Therefore, M2
was proposed to be hydroxy DCDQ.
METABOLITE M3: FROM IN VITRO, AND IN VIVO RAT AND DOG STUDIES
The [M+H]* for M3 was observed at m/z 245. The product ions of m/z 245 mass
spectrum of M3 and the proposed fragmentation scheme indicated an increase of 16 Da,
suggesting monohydroxylation. Loss of ethylideneamine generated the fragment at
m/z 202, which was 16 Da higher than the corresponding ion at m/z 186 for SAX-187.
The fragment ions at m/z 158 and 144 were the same as in the product ion spectrum of
DCDQ. This indicated that the hydroxylation occurred in the cyclopentane portion of the
molecule as shown. Therefore, M3 was proposed to be hydroxy DCDQ.
METABOLITE M4: FROM IN VITRO AND IN VIVO RAT STUDIES
The [M+H]* for M4 was observed at m/z 245. The product ions of m/z 245 mass
spectrum of M4 and the proposed fragmentation scheme indicated an increase of 16 Da,
suggesting monohydroxylation. Loss of H2O from the molecular ion generated the
fragment at m/z 227. The product ion at m/z 144 was also observed for DCDQ,
indicating that the hydroxylation occurred in the cyclopentane portion of the molecule as
shown. This was also consistent with the presence of the m/z 184 product ion,
generated by loss of ethylideneamine and H2O from the corresponding ion at m/z 186 for
DCDQ. The measured accurate mass for this ion was 184.1120 Da, which was within
3.6 ppm of the theretical mass for Ci3H14N. Therefore, M4 was proposed to be hydroxy
DCDQ.
METABOLITE M5: FROM IN VITRO STUDIES
The [M+H]* for M5 was observed at m/z 243. The measured accurate mass for
M5 was 243.1478 Da, which was within 7.9 ppm of the theoretical mass for C15H19N2O.
This corresponded to the addition of one oxygen and loss of two hydrogen atoms
compared with the molecular formula for DCDQ. A fragment ion at m/z 130 was 2 Da
less than the corresponding ion for DCDQ, suggesting the formation of the imine.
LC/MS with D2O substituted for H2O in the mobile phase confirmed that no
exchangeable protons existed for M5, indicating that M5 was an N-oxide. Therefore, M5
was proposed to be the N-oxide of DCDQ imine.
METABOLITE M6: FROM IN VITRO AND IN VIVO DOG STUDIES
The [M+H]* for M6 was observed at m/z 449. The product ions of m/z 449 mass
spectrum of M6 and the proposed fragmentation scheme indicated a loss of 176 Da from
the molecular ion generated a fragment at m/z 273, indicating that M5 was a glucuronide
conjugate. Further loss of 44 Da from m/z 273 generated m/z 229, which was also the
molecular ion for DCDQ. Therefore, M6 was proposed to be the carbamoyl glucuronide
ofDCDQ.
METABOLITE M7: FROM IN VITRO AND IN VIVO RAT AND DOG STUDIES
The [M+H]* for M7 was observed at m/z 243. The product ions of m/z 243 mass
spectrum of M7 and the proposed fragmentation scheme indicated loss of
methyleneamine, ethylideneamine from the molecular ion generated the product ions at
m/z 214 and 200, which were 14 Da more than the corresponding ions at m/z 200 and
186, respectively, for DCDQ. This suggested the addition of one oxygen atom and loss
of two hydrogen atoms from DCDQ. The product ions at m/z 132,144 and 158 were the
same as DCDQ, which indicated that the biotransformation occurred in the pyridine and
cyclopentane rings. LC/MS with D20 substituted for H2O in the mobile phase confirmed
that there was only one exchangeable proton for M7, which was from the NH group in
the diazepane ring^ Therefore, M7 was proposed to be a keto DCDQ.
METABOLITE M8: FROM IN VIVO RAT STUDIES
The [M+Hf for MB was observed at m/z 325. The product ions of m/z 325 mass
spectrum of MS and the proposed fragmentation scheme indicated a loss of propene
from the molecular ion generated the product ion at m/z 283, indicating the
biotransformation did not occur on the cyclopentane ring. Loss of methyleneamine,
ethylideneamine from the product ion at m/z 283 and subsequent loss of sulfate group
generated the product ions at m/z 158 and 144, respectively. Loss of ethylideneamine
from the molecular ion generated the product ion at m/z 282 and subsequent loss of the
sulfonate group and H2O generated the product ions at m/z 202 and 184, respectively.
The fragment ion at m/z 132 was the same as for DCDQ indicating that the diazepane
portion was not the site of biotransformation. Therefore, MS was proposed to be sulfate
conjugate of hydroxy DCDQ.
METABOLITE M9: FROM IN VIVO RAT AND DOG STUDIES
The [M+H]* for M9 was observed at m/z 421. The product ions of m/z 421 mass
spectrum of M9 and the proposed fragmentation scheme indicated a loss of 176 Da from
the molecular ion generated the fragment ion at m/z 245, which indicated
glucuronidation of hydroxy DCDQ. Loss of ethylideneamine and glucuronic acid
generated the fragment at m/z 202, which was 16 Da higher than the corresponding ion
at m/z 186 for DCDQ. The fragment ion at m/z 187 suggested that the biotransformation
occurred in the cyclopentane ring. Therefore, M9 was proposed to be a glucuronide of
hydroxy DCDQ.
METABOLITE M10
The [M+H]+ for M10 was observed at m/z 245. The product ions of m/z 245
mass spectrum of M10 and the proposed fragmentation scheme indicated an increase of
16 Da, suggesting monohydroxylation. The fragment Ions at m/z 171 and 186 were the
same as in the product ion spectrum of DCDQ, indicating that the hydroxylation occurred
in the diazepane portion of the molecule as shown. Therefore, M10 was proposed to be
hydroxy DCDQ.
METABOLITE M11: FROM IN VIVO RAT STUDIES
The [M+H]* for M11 was observed at m/z 287. The product ions of m/z 287
mass spectrum of M11 and the proposed fragmentation scheme indicated a loss of H20
from the molecular ion generated the fragment ion at m/z 269. Further loss of 42 Da
generated m/z 227, which indicated acetylation. The fragment ions at m/z 171 and 186
were the same as in the product ion spectrum of DCDQ, indicating that the
biotransformations occurred in the diazepane portion of the molecule as shown.
Therefore, M11 was proposed to be acetylated hydroxy DCDQ.
METABOLITE M12: FROM IN VIVO RAT STUDIES
The [M+H]+ for M12 was observed at m/z 309. The product ions of m/z 309
mass spectrum of M12 indicated a loss of 80 Da generated the product ion at m/z 229,
which is the molecular ion of DCDQ. This indicated sulfation. Further loss of
methyleneamine, ethylideneamine generated the product ions at m/z 200 and 186,
which were the same for DCDQ. Therefore, M12 was proposed to be the N-sulfate of
DCDQ.
METABOLITE M13: FROM IN VIVO RAT STUDIES
The [M+Hf for M13 was observed at m/z 325. The product ions of m/z 325
mass spectrum of M13 and the proposed fragmentation scheme indicated a loss of 80
Da from [M+H]+ yielded m/z 245 which was 16 Da larger than the [M+H]+ for DCDQ.
This indicated that M13 was a sulfate conjugate of hydroxy DCDQ. Therefore, M13 was
proposed to be sulfate conjugate of hydroxy DCDQ.
METABOLITE M14: FROM IN VIVO RAT STUDIES
The [M+H]* for M14 was observed at m/z 305. The product ions of m/z 305
mass spectrum of M14, the product ions of m/z 225 mass spectrum and the proposed
fragmentation scheme for M14 indicated a loss of 80 Da from the molecular ion
generated the ion at m/z 225, which indicated that M14 was a sulfate. Further loss of
ethylideneamine, and ethylidene-methyl-amine generated the product ions at 182 and
167, respectively, which were 4 Da less than the corresponding ions for DCDQ at m/z
186 and 171, respectively, which indicated metabolism of the cyclopentane group.
Therefore, M14 was proposed to be the sulfate conjugate of di-dehydro DCDQ.
METABOLITE M15: FROM IN VIVO DOG STUDIES
The [M+Hf for M15 was observed at m/z 245. The product ions of m/z 245
mass spectrum of M15 and the proposed fragmentation scheme indicated a fragment
ion at mil 187 was 16 Da more than the corresponding ion at m/z 171 for DCDQ,
indicating hydroxylation of the cyclopentane or the pyridine ring. The fragment ion at
m/z 130 was 2 Da less than the corresponding ion for DCDQ indicating the formation of
imine. LC/MS with D20 substituted for H2O in the mobile phase confirmed that there
was only one exchangeable proton for M15. Therefore, M15 was proposed to be
hydroxy DCDQ imine.
METABOLITE M16: FROM IN VIVO DOG STUDIES
The [M+HJ* for M16 was observed at m/z 325. The product ions^f m/z 325
. -. rv , v. *J,' -,
mass spectrum of M13 and the proposed fragmentation scheme indicated a loss of
80 Da from the molecular ion generated the product ion at m/z 245, indicating sulfation.
Loss of propene from the molecular ion generated the product ion at m/z 283, indicating
the biotransformation did not occur on the cyclopentane ring. Loss of ethylideneamine
generated the product ion at m/z 282 and subsequent loss of sulfate group andH2O
generated the product ions at m/z 202 and 184 respectively. The product ion at
m/z 148,16 Da more than the corresponding ion at 132 for DCDQ, and the m/z 282
product ion indicated that the hydroxylation occurred in the benzyl group of the molecule
as shown. Therefore, M16 was proposed to be sulfate conjugate of hydroxy DCDQ.
METABOLITE M17: FROM IN VIVO DOG STUDIES
The [M+H]+ for M17 was observed at rn/z 257. The measured accurate mass of
[M+Hf was 257.1292 Da, which was within 0.8 ppm of the theoretical mass for
C15H17N2O2. This corresponded to the addition of two oxygen atoms and loss of
4 hydrogen atoms compared to the molecular formula of DCDQ. Loss of 44 Da from the
molecular ion generated the fragment at m/z 213. The measured accurate mass of this
fragment was 213.1376 Da, which was within 7.6 ppm of the theoretical mass for
C14Hi7N2. This confirmed that the loss of 44 was from the neutral loss of CO2, indicating
that M17 was a carboxylic acid. Further loss of cyclopentene, pentane, propene and
HCN from m/z 213 generated the fragments at m/z 145,171 and 186 respectively. The
product ion at m/z 130 was 2 Da less than the corresponding ion at m/z 132 for DCDQ
indicating the formation of an imine. LC/MS with D2O substituted for H20 in the mobile
phase confirmed that there was only one exchangeable proton for M17, which was from
the carboxylic acid group. Therefore, M17 was proposed to be Benzo-diazepinylcyclopentanecarboxylic
acid (diazepinyl DCDQ carboxylic acid).
METABOLITE M18: FROM IN VIVO DOG STUDIES
The [M+Hf for M18 was observed at m/z 243. The product ions of m/z 243
mass spectrum of M18 and the proposed fragmentation scheme indicated a loss of
propene and ethylideneamine groups from the molecular ion generated the product ion
at m/z 158. Loss of methyleneamine, ethylideneamine from the molecular ion generated
the product ions at m/z 214 and 200, which were 14 Da more than the corresponding
ions at m/z 200 and 186, respectively, for DCDQ. This suggested the addition of one
oxygen atom and loss of two hydrogen atoms from DCDQ. The product ion at m/z 146,
14 Da more than the corresponding ion at m/z 132 for DCDQ, and the m/z 200 product
ion indicated that the modification occurred on the benzyl group. LC/MS with D20
substituted for H2O in the mobile phase confirmed that there was only one exchangeable
proton for M14, which was from the NH group in the diazepane ring. Therefore, M18
was proposed to be a keto DCDQ.
METABOLITE M19: FROM IN VIVO DOG STUDIES
The [M+Hf for M19 was observed at m/z 245. The product ions of m/z 245
mass spectrum of M19 and the proposed fragmentation scheme indicated an increase of
16 Da, suggesting monohydroxylation. The product ir-ns at m/z 216, 202 and 187 were
16 Da more than the corresponding ions at m/z 200,186 and 171, respectively, for
DCDQ, indicating that diazlpane group was not the site of modification. Loss of
propenefrom the molecular ion generated the fragment at m/z 203 and further loss of
methyleneamine and ethylideneamine generated the fragment ions at m/z 174 and
These were 16 Da more than the corresponding ions for DCDQ, indicating that
hydroxylation occurred at either the benzene or pyridine group. Therefore, M19 was
proposed to be hydroxy DCDQ.
PRODUCT P3: FROM IN VIVO STUDIES
The [M+H]+ for P3 was observed at m/z 227. The product ions of m/z 227 mass
spectrum of P3 and the proposed fragmentation scheme indicated the molecular weight
forP3 was 2 Da less than DCDQ suggesting the formation of a double bond. The
fragment ion at m/z 130 was 2 Da less than the corresponding ion for DCDQ, suggesting
the formation of an imine. Therefore, P3 was proposed to be DCDQ imine.
IDENTIFICATION OF METABOLITES M7, M9 AND M13 IN RAT URINE
FOLLOWING A SINGLE ORAL 50 MG/KG ADMINISTRATION OF DCDQ
SYNOPSIS
This study was designed to obtain rat urine for metabolite isolation and to obtain
more specific structural identification for selected metabolites of DCDQ. Three male and
three female rats were given a single 50 mg/kg dose of DCDQ. Urine was collected at
0-12 and 12-24 hour intervals. DCDQ metabolites M7 (keto DCDQ), M9 (hydroxy DCDQ
glucuronide) and M13 (hydroxy DCDQ sulfate) were isolated from the urine by a two
stage semi-preparative HPLC method in low microgram quantities sufficient for NMR
spectroscopic analysis. Based upon MS and NMR spectroscopic analysis the site of
metabolism for M7 and M13 was at 17 position 17. The site of metabolism for M9 was at
position 13.
INTRODUCTION
When incubated with rat liver microsomes in the presence of NADPH and
UDPGA, [14C]DCDQ was converted to several oxidative metabolites. A previous
metabolism study in rats showed that DCDQ was extensively metabolized and oxidative
metabolism was the major metabolic pathway in rats. Phase II metabolites including
sulfate and a glucuronide of hydroxy DCDQ were also detected in rats. The present
study was designed to obtain rat urine for metabolite isolation and to obtain more
specific structural identification for selected metabolites of DCDQ.
MATERIALS AND METHODS
Materials
DCDQ hydrochloride was synthesized by Wyeth Research as described above.
Polysorbate 80 was obtained from Mallinckrodt Baker (Phillipsburg, NJ) and
methylceHulose was from Sigma-Aldrich (Milwaukee, Wl), Solvents used for extraction,
and for chromatographic analysis were HPLC or ACS reagent grade from EMD
Chemicals (Gibbstown, NJ). Deuterated dimethyl sulfoxide (DMSO-d6) was purchased
from Cambridge Isotope Laboratories (Andover, MA). NMR tubes (3mm) were
purchased from Wilmad Glass Co. (Buena, NJ).
METHODS
DRUG ADMINISTRATION AND SPECIMEN COLLECTION
Dose preparation, animal dosing and specimen collection were performed at
Wyeth Research, Collegeville, PA. The dose vehicle contained 2% (v/v) Tween 80 and
0.5% (v/v) methylceHulose in water. On the day of dosing, non-labeled DCDQ (205.7
mg) was dissolved in the vehicle to a final concentration of approximately 10 mg/mL.
Three male rats weighing from 413 to 474 grams and three female rats weighing
from 272 to 290 grams at the time of dosing were purchased from Charles River
Laboratories (Wilmington, MA). Non-fasted rats were given a single 50 mg/kg target
dose of DCDQ at a volume of 5.0 mL/kg via intragastric gavage. Animals were provided
standard rat chow and water ad libitum, and were kept in metabolism cages individually.
Urine was collected into containers on dry ice at 0-12 and 12-24 hour intervals,
and stored at approximately -70°C until fraction collection.
ANALYSIS OF RAT URINE BY LIQUID CHROMATOGRAPHY/MASS
SPECTROMETRY
Rat urine samples were analyzed by LC/MS to characterize the DCDQ
metabolites present in the rat urine samples used for metabolite isolation. The HPLC
system used for LC/MS analysis was an Agilent Model 1100 HPLC system (Agilent
Technologies, Palo Alto, CA) equipped with a binary pump, autosampler and diode array
UV detector. The autosampler temperature was set to 10°C. The UV detector was set
to monitor 190 to 400 nm. Separations were accomplished with a Supelco Discovery
C18 column (250 x 2.1 mm x 5 urn). The column temperature was 20°C. The mobile
phase gradient program used was as described below.
Mobile phase A: 10 mM Ammonium acetate in water, pH 4.5
Mobile phase B: Methanol
(Table Removed)

The mass spectrometer used for metabolite characterization was a Finnigan LCQ
ion trap mass spectrometer (ThermoElectron Corp., San Jose, CA). It was equipped
with an electrospray ionization (ESI) interface and operated in the positive ionization
mode. Settings for the mass spectrometer are listed below.
Table 28 Finnigan LCQ Ion Trap Mass Spectrometer Settings
Nebulizer gas 90 arb. units
Auxiliary gas 10 arb. units
Spray voltage 3.5 KV
Heated capillary temp. 200 °C
Full scan AGC setting 4x107
Relative collision energy 30%
METABOLITE ISOLATION BY LIQUID CHROMATOGRAPHY
The HPLC system used for metabolite isolation consisted of a Waters Prep LC
4000 pump, a Waters 2767 Sample Manager for sample injection, Waters 996 diode
array UV detector and a Gilson FC204 fraction collector (Gilson, Inc., Middleton, Wl).
The UV detestor was set to monitor 210-450 nm. The fraction collector was set to
collect fractions at 1 min intervals. The HPLC mobile phase gradient was as described
above for LC/MS analysis except that the flow rate was 4.7 mL/min. Mobile phases
were as described below for each HPLC Condition. No mass spectral analysis was
conducted during fraction collection.
Two HPLC Conditions were used to isolate metabolites. HPLC Condition 1 was
used to fractionate metabolites from rat urine. HPLC Condition 2 was used to further
purify the DCDQ metabolite fractions collected using HPLC Condition 1. The columns
and mobile phases used for HPLC Conditions 1 and 2 are listed below.
HPLC Condition 1
Column: Supelco Discovery C18 semi-preparative column (250 x 10 mm, 5 nm)
(Supelco, Bellefonte, PA).
Mobile phase A: 10 mM Ammonium acetate in water, pH 4.5
Mobile phase B: Methanol.
HPLC Condition 2
Column: Zorbax SB-CN semi-preparative column (250 x 9.4 mm, 5 urn) (Agilent
Technologies)
Mobile phase A: 0.02% Trifluoroacetic acid in water
Mobile phase B: 0.02% Trifluoroacetic acid in methanol
. Fractions containing metabolites M7, M9 and M13 from HPLC Condition 2 were
combined and evaporated to dryness under nitrogen using a Zymark TurboVap (Caliper
Life Sciences, Hopkinton, MA). Dried metabolites were submitted for NMR
spectroscopic analysis.
NUCLEAR MAGNETIC RESONANCE (NMR) SPECTROSCOPY ANALYSIS OF
ISOLATED M7, M9 AND M13
For NMR spectroscopy, samples of isolated DCDQ metabolites M7, M9 and M13
were each dissolved in 150 uL of 100% DMSO-d6 and transferred to individual 3 mm
NMR tubes under a nitrogen gas atmosphere. One-dirnensional (1D) proton NMR and
two-dimensional (2D) NMR (COSY, ROESY) data were collected on a Varian Inova 500
MHz NMR spectrometer (Palo Alto, CA) equipped With a Naiorac 5mm z-gradierit
indirect detection probe (Varian).
Data Analysis
ThermoFinnigan Xcalibur software (version 1.3) was used to control the LC/MS
system and analyze LC/MS data. Micromass MassLynx software (version 4.0) was used
for control of the HPLC equipment used for fraction collection. NMR spectroscopic data
were collected, processed and displayed using the VNMR program (version 6.1C,
Varian).
RESULTS
DCDQ METABOLITE CHARACTERIZATION BY LC/MS AND
NMR SPECTROSCOPY
In this study, DCDQ metabolites M7, M9 and M13 were isolated in sufficient
amounts to conduct NMR spectroscopic analysis for more detailed structural
characterizations. The structural identifications for M7 (keto DCDQ), M9 (hydroxy
DCDQ glucuronide) and M13 (hydroxy DCDQ sulfate) presented in this report shall
replace those presented in previous reports. Structures of DCDQ, M7, M9 and M13,
along with their NMR numbering schemes, are summarized in Figure 5. Identification of
M7, M9 and M13 by mass and NMR spectroscopy is discussed below.
DCDQ
The mass spectral and NMR characteristics of DCDQ standard were examined
for comparison with the metabolites. In the LC/MS spectrum of DCDQ, a protonated
molecular ion, [M+H]*, was observed at m/z 229. The product ions of m/z 229 mass
spectrum of DCDQ obtained from collision-induced dissociation (CID), and the proposed
fragmentation scheme indicated a loss of methyleneamine and ethylideneaminefrom the
molecular ion generated the product ions at m/z 200 and 186, respectively. Loss of
propene from the molecular ion generated m/z 187 and further loss of ethylideneamine
generated m/z 144. Loss of the cyclopentyl-methyleneamine group generated the
m/z 132 product ion.
Table 29 summarizes the 1HNMR chemical shift data for DCDQ. These data
were used for comparison with the isolated metabolites.
(Table Removed)

'•Chemical shifts are referenced to residual internal TMS (0.0 ppm) for 1H.
b-Several proton assignments could not be made because of overlap in the 3.35 to
3.15 ppm region.
Metabolite M7
The [M+H]+ for M7 was observed at m/z 243. The product ions of m/z 243 mass
spectrum of M7 and the proposed fragmentation scheme indicated a loss of
methyleneamine, ethylideneamine from the molecular ion generated the product ions at
m/z 214 and 200, respectively, which were 14 Da larger than the corresponding ions at
m/z 200 and 186, respectively, for DCDQ. This suggested the addition of one oxygen
atom and loss of two hydrogen atoms from DCDQ. The product ions at m/z 132,144
and 158 were the same as for DCDQ, which indicated the site of biotransformation as
the cyclopentane ring.
Table 30 lists the chemical shifts and assignments for M7. The metabolite was
assigned using information from the 1D NMR spectrum and the 2D COSY spectrum.
The 1D1H NMRspectrum showed that the aromatic ring was intact with three aromatic
resonances coupled in series. With the available data, it was not possible to distinguish
H12 from H14. The protons in the dizaepine ring were assigned from the salt
resonances (H4) at 9.10 and 8.62 ppm. The 2D COSY data showed that these protons
were coupled to the protons at 3.20 ppm (H3) and 4.18 and 4.15 ppm (H5). The H3
protons were also coupled to protons at 3.34 and 3.06 (H2). These results confirmed
that the dizaepine ring was intact.
(Table Removed)

a'Chemical shifts are referenced to residual internal DMSO-d6 at 2.49 ppm for 1H.
bThe assignments for H12 and H14 might be interchanged.
The 1D1H NMRspectrum also showed a change occurred in the cyclopentyi
region versus DCbQ because there were three resonances upfield of 2.5 ppm while for"
DCDQ, there were seven resonances. The assignment of the remaining protons began
with the H11 protons. The resonances at 3.16 ppm and 3.01 ppm were assigned to H11
based on comparison to the coupling constants observed for DCDQ The resonance at
3.01 ppm was a triplet and the resonance at 3.16 ppm was a doublet of doublets. These
were also observed for DCDQ. The H11 protons were both coupled to a resonance at
2,59 ppm (H10). The-H10 resonance was coupled to one other resonance at 3.47 ppm
(H9). The H9 resonance was coupled to a methylene pair at 2.53 ppm and 1.76 pprn
(H15). Tlie HIS resonances were coupled to another methylene pair at 2.32 ppm and
2.14 ppm (H16). There were no resonances assignable to H17, which indicated the site
of metabolism as the C17 position. The downfield shift of the H16 protons would be
consistent with a carbonyl oxygen at C17. Therefore, M7 was identified as 17-keto
DCDQ. , .
Metabolite M9
M9 generated a [M+H]+ at m/z 421. The product ions of m/z 421 mass spectrum
of M9 and the proposed fragmentation scheme indicated a loss of 176 Da from the
molecular ion generated m/z 245,16 Da larger than the DCDQ molecular ion, which
indicated glucuronidation of hydroxy DCDQ. Loss of ethylideneamine from [M+H]+
yielded m/z 378. This indicated an unchanged ethyleneamine moiety. Loss of
glucuronic acid (176 Da) from m/z 378 yielded m/z 202, which was 16 Da higher than
the corresponding ion at m/z 186 for DCDQ. This eliminated the three methylene groups
of the cyclopropane ring as sites of metabolism. The product ion at m/z 203 was 16 Da
larger than the corresponding ion at 187 for DCDQ. These data were consistent with
either the benzyl or tetrahydropyridine group as the site of metabolism,
Table 31 lists the NMR chemical shifts and assignments for M9 using the
numbering scheme in Figure 5. Much of the metabolite could be assigned using
information from the 1D NMR spectrum and results from 2D COSY analysis, showing
the through-bond correlations in M9, and ROESY analysis, showing through-space NOE
close contacts in M9, experiments. The resonances from the methylene protons on C2
were not assigned because of overlap. Their resonances were located between 3.35
ppm and 3.15 ppm. The upfield regions of the NMR spectra for M9 DCDQ were
identical, Further analysis of this region using a COSY experiment confirmed that the
pentyl ring system was intact. Also visible in the 1D1H NMR spectrum for M9 were the
resonances from the glucuronic acid. Several of these resonances could not be
unambiguously assigned because of spectral overlap. There was an adequate amount
of metabolite for the unassigned protons to resonate in the 3.35 to 3.15 ppm region.
a-Chemical shifts are referenced to residual internal DMSO at 2.49 ppm for 1H.
(Table Removed)

b-Several proton assignments could not be made because of overlap in the 3.35 to
3.15 ppm region.
Inspection of the 500 MHz 1D1H NMR spectrum showed that the resonances for
the aromatic region were changed from the NMR spectrum of DCDQ. Two of these
aromatic resonances remained from the three for DCDQ, Coupling at 2.5 Hz between
these aromatic resonances is characteristic of a mefa orientation between the protons.
This placed the glucuronic acid at the C13 position. The location of the glucuronic acid
was further supported by the results of a ROESY experiment that showed H12 had
NOEs to the H5 proton and H14 had an NOE to H9. These results positioned H12 and
H14 at opposite ends of the aromatic ring. Both aromatic protons also had NOEs to the
anomeric proton of the glucuronic acid ring. All these results were consistent with the
glucuronic acid conjugation being at C13.
Metabolite M13
The [M+H]+ for M13 was observed at m/z 325. The product ions of m/z 325
mass spectrum of M13 and the proposed fragmentation scheme indicated a loss of 80
D from [M+Hf yielded m/z 245, which was 16 Da larger than [M+H]+ for DCDQ. This
indicated that M13 was a sulfate conjugate of hydroxy DCDQ. Loss of ethylideneamine
from the molecular ion yielded m/z 282. The presence of product ions at m/z 144 and
132, also observed for DCDQ, indicated that one of the three methylene positions of the
cyclopentane ring was the site of metabolism.
Table 32 lists the chemical shifts and assignments for M13. The metabolite was
assigned using information from the 1D1H NMR spectrum, 2D COSY spectrum and 2D
ROESY spectrum. The 1D1H NMR spectrum for M13 showed that the aromatic ring
was intact with three coupled protons at 7.15 ppm (H12), 6.91 ppnv(H13) and 7.23 ppm
(H14). The assignments were confirmed by observing an ROE from H12 to the
resonances at 4.17 ppm and 4.14 ppm which were identified as H5. The protons in the
dizaepine ring were assigned from the salt resonances (H4) at 9 04 and 8.57 ppm. The
2D COSY data showed that these protons were coupled to the protons at 3.22 ppm and
3.20 ppm (H3) and 4.17 and 4.14 ppm (H5). The H3 protons were also coupled to
protons at 3.34 and 3.14 (H2). These results confirmed that the dizaepine ring was
intact.
(Table Removed)

Chemical shifts are referenced to residual internal DMSO at 2.49 ppm for 1H.
The 1D1H NMR spectral data (Table 32) showed that a change occurred in the
cyclopentyl region because there were five resonances upfield of 2.5 ppm for M13 while
in the DCDQ NMR spectrum, there were seven resonances. The protons at position 11
were assigned based on their similarity to those for DCDQ. The triplet resonance at
2.68 ppm was unique to DCDQ. This resonance was coupled to a resonance at 3.23
ppm (H11) and another at 2.40 ppm (H10). H10 was coupled to a resonance at 3.15
ppm (H9) and weakly coupled to 4.29 ppm (H17). H9 was coupled to a methylene pair
at 2.26 ppm and 1.33 ppm (both H15). This methylene pair was coupled to a second
methylene pair at 1.97 ppm and 1.67 ppm (both H16). The H16 methylene was coupled
to H17. One proton was missing from the cyclopentane ring and the large downfield
shift of the remaining proton was indicative of a nearby heteroatom. All these data were
consistent with the sulfate group present at the C17 position. Therefore, M13 was
identified as 17-hydroxy DCDQ sulfate.
DISCUSSION
The present study was designed to obtain rat urine for metabolite isolation and to
obtain more specific structural identification for selected metabolites of DCDQ. Three
male and three female rats were given a single 50 mg/kg dose of DCDQ. Urine was
collected at 0-12 and 12-24 hour intervals. DCDQ metabolites M7 (keto DCDQ), M9
(hydroxyl DCDQ glucuronide) and M13 (hydroxyl DCDQ sulfate) were isolated from the
urine by a two stage semi-preparative HPLC method in low microgram quantities
sufficient for NMR spectroscopic analysis. Based upon MS and NMR spectroscopic
analysis the site of metabolism for M7 and M13 was at 17 position 17. The site of
metabolism for M9 was at position 13. The structural identifications for M7, M9 and M13
identified through this study further refine those of the in vivo rat study discussed above.
IN VIVO METABOLISM OF [14C] DCDQ IN HEALTHY HUMAN
SUBJECTS FOLLOWING ORAL ADMINISTRATION
The metabolite profiles of DCDQ in plasma and urine of healthy human subjects
receiving a single or multiple oral doses of DCDQ at various dosages were determined.
In addition, relative concentrations of the major DCDQ metabolite (M6, carbarmoyl
glucuronide) were determined in selected samples.
DCDQ and several DCDQ metabolites were identified in plasma and urine.
DCDQ carbamoyl glucuronide (M6) was the predominant drug-related component in
both plasma and urine. DCDQ imine N-oxide (M5), unchanged DCDQ, DCDQ imine
(P3) and other relatively minor drug-related components were also observed in plasma.
Unchanged DCDQ, pCDQ N-oxide glucuronide (M40), hydroxyl DCDQ glucuronide
(M38), hydroxyl DCDQ carbamoyl glucuronide (M37) and a number of other relatively
minor drug-related components were excreted in urine.
The concentrations of M6 in plasma increased with increased dosage, and large
individual variations were observed. Plasma M6 concentrations decreased over time
from 6 to 24 hour post-dose. The ratios of M6-to-DCDQ plasma concentrations were
higher at 6 hour than at 12 and 24 hour post-dose. At 6 hour post-dose, the average
ratios ranged from 35.4 to 76.6. There were no statistically significant differences in M6
concentrations and the M6-to-DCDQ ratios between fasted and fed subjects receiving
300 mg of DCDQ. The average M6-to-DCDQ ratios ranged from 84 to 1018 in urine.
The results show that DCDQ underwent phase I and phase II metabolism in
healthy human subjects receiving DCDQ orally, and carbamoyl glucuronidation was the
major metabolic pathway. In contrast to animal studies, formation of the carbamoyl
glucuronide (M6) was the major metabolic pathway in humans, and M6 was the
predominant drug-related metabolite in human plasma and urine.
MATERIALS AND METHODS
METHODS
DCDQ hydrochloride with a chemical purity of 98.6% was synthesized by Wyeth
Research (Pearl River, NY). DCDQ carbamoyl glucuronide was synthesized by
Chemical Development at Wyeth Research (Montreal, Canada), and had a purity of
95.5%. The internal standard (d8-DCDQ, lot L27347-140-A) was synthesized by the
Radiosynthesis group at Wyeth Research (Pearl River, NY). The reported deuterium
distribution was d0-d5 0%, de 0.1%, d7 2.7%, and d8 97.1%. Solvents used for extraction
and for chromatographic analysis were HPLC or ACS reagent grade from EMD
Chemicals (Gibbstown, NJ).
METHODS
DRUG ADMINISTRATION AND SPECIMEN COLLECTION
Drug administration and specimen collection were performed in a randomized,
double-blinded, placebo-controlled, ascending single dose study of the safety,
tolerability, pharmacokinetics, and pharmacodynamics of DCDQ administered orally to
healthy subjects and subjects with schizophrenia and schizoaffective disorder. The
specimens were stored at approximately -70 °C until analysis for metabolite profiles and
for ratios of carbamoyl glucuronide (M6) to DCDQ.
SAMPLE PREPARATION
Two subjects with medium and high exposure to DCDQ in the 25 mg multiple
ascending dose study were also analyzed by LC/MS for metabolite profiles. The 8 hrplasma
samples collected on day 1 and day 14 from subjects 9 and 41 were processed
and analyzed as described below. No internal standard was added to the samples
analyzed for metabolite profiles.
Plasma samples from fasted subjects 25, 28 and 30 in the 50 mg single dose
group, fasted subjects 50, 51, 54 in the 200 mg single dose group, fasted subjects 74,
76, 79 in the 300 mg single dose group, fed subjects 83, 84, 86 in the 300 mg single
dose group and fasted subjects 92, 94, 96 in the 500 mg single dose group were
analyzed for DCDQ carbamoyl glucuronide (M6) concentrations. The internal standard
d8-DCDQ (25 fit of 200 ng/mL methanol solution) was added to 100 nL of the plasma
samples, followed by the addition of 300 ^L of acetonitrile. The samples were mixed
and centrifuged at 14000 rpm in an Eppendorf 5415C centrifuge (Brinkman Instruments
Inc., Westbury, NY) for 10 minutes. The supernatant of each sample was transferred to
a clean tube and evaporated to dryness under a stream of nitrogen in a TurboVap LV
evaporator (Caliper Life Sciences, Hopkinton, MA). The residue was reconstituted with
50 pi. of methanol followed by the addition of 150 \iL of water. The sample was mixed
and centrifuged as described above. The supernatant was analyzed by LC/MS/MS
analysis. Samples for standard curves were prepared with control plasma spiked with
synthetic M6> The concentrations of M6 used for the standard curve ranged from 0 to
2500 ng/mL plasma.
The 0-4, 4-12 and 12-24 hr urine samples from the same subjects in the single
dose groups were analyzed for ratios Qf M6 to DCDQ. The internal standard was not
used in the analysis of urine samples. The samples were diluted for 20-fold with a
control urine sample and directly analyzed by LC/MS. To estimate M6-to-DCDQ ratios in
human urine, control urine samples were spiked with 200 ng/mL of DCDQ and 1000,
5000, or 10000 ng/mL of DCDQ carbamoyl glucuronide, and were analyzed by LC/MS.
LIQUID CHROMATOGRAPHY/MASS SPECTROMETRY
Three LC/MS systems were used in this work. LC/MS System 1 was used for analysis
of plasma and urine samples for metabolite characterization. LC/MS System 2 was
used to provide additional MS/MS data for characterization of DCDQ metabolites in
urine. LC/MS System 3 was used for semi-quantitative analysis of metabolite M6
(DCDQ carbamoyl glucuronide) in plasma and urine samples.
IDS
LC/MS SYSTEM 1
LC/MS System 1 was used for analysis of plasma and urine samples for metabolite
characterization. The HPLC equipment used with this LC/MS System consisted of an
Agilent Model 1100 HPLC system (Agilent Technologies, Palo Alto, CA) including an
autosampler, binary pump and diode array UV detector. The UV detector was set to
monitor 210 to 350 nm. The HPLC mobile phase consisted of 10 mM ammonium
acetate, pH 4.5 (A) and methanol (B), and was delivered at 0.2 mL/min. The linear
mobile phase gradient (HPLC Gradient 1) is shown below. During LC/MS sample
analysis, up to 6 min of the initial flow was diverted away from the mass spectrometer
prior to evaluation of metabolites.
The mass spectrometer used for metabolite characterization with LC/MS System 1 was
a Finnigan LCQ-Deca ion trap mass spectrometer (Thermo Electron, San Jose, CA).
This mass spectrometer was equipped with an electrospray ionization (ESI) interface
and operated in the positive ionization mode. Settings for the LCQ mass spectrometer
are listed below.
Finnigan LCQ Mass Spectrometer Settings
Spray voltage 4.5 kV
Heated capillary temp. 200 °C
Nebulizer gas pressure 50 psi
Auxiliary gas setting 60
Full scan AGC setting 5 x 107
Relative collision energy 30%
LC/MS System 2
LC/MS System 2 was used to provide additional MS/MS data for characterization of
DCDQ metabolites in urine. The HPLC equipment used with LC/MS System 2 consisted
of a Waters model 2695 HPLC system (Waters Corp., Milford, MA). It was equipped
with a built-in autosampler and a model 996 diode array UV detector. The UV detector
was set to monitor 210-400 nm. The HPLC column, mobile phases, flow rate, diversion
of flow away from the mass spectrometer and gradient were as described above for
LC/MS System 1. The column temperature was 25°C.
The mass spectrometer used for metabolite characterization with LC/MS System 2 was
a Micromass Quattro Micro triple quadrupole mass spectrometer (Waters Corp.). This
mass spectrometer was equipped with an electrospray interface and operated in the
positive ionization mode. Settings for this mass spectrometer are listed below.
(Table Removed)

• ' 4* ' ..
LC/MS System 3 was used for semi-quantitative analysis of metabolite M6 (DCDQ
carbamoyl glucuronide) in plasma and urine samples. The HPLC equipment for this
LC/MS System consisted of a Thermo Surveyor HPLC (Thermo Electron Corp., San
Jose, CA), including a Surveyor MS pump and autosampler. Separations were
accomplished on a 5 micron Phenomenex Luna C18(2) column, 150 x 2 mm
(Phenomenex, Torrance, CA). The autosampler and column temperatures were set at
5°C and 40°C, respectively. The HPLC mobile phase consisted of 10 mM ammonium
acetate (A) and methanol (B), and was delivered at 0.2 mL/min. The linear mobile
phase gradient {HPLC Gradient 2) is shown below. During LC/MS sample analysis, up
to 3 min of the initial flow was diverted away from the mass spectrometer prior to
evaluation of metabolites.
(Table Removed)

The mass spectrometer used for semi-quantitative anslysis with LC/MS System 3 was a
Finnigan TSQ Quantum triple quadrupole mass spectrometer (Thermo Electron Corp.).
This mass spectrometer was equipped with an electrospray interface and operated in
the positive ionization mode. Settings for this mass spectrometer are listed below.
Finnigan TSQ Quantum Mass Spectrometer Settings
Spray voltage 4.5 kV
Capillary temperature , 250°C
Q1 mass resolution setting 0.8 Da width at half height
Q3 mass resolution setting 0.6 Da width at half height
Nebulizer gas pressure 30 arb. units
Auxiliary gas setting 50 arb. units
Collision gas pressure LSmtorr
LC/MS/MS analysis in the selected reaction monitoring (SRM) mode (LC/SRM) was
conducted for DCDQ and M6 using the following settings.
LC/SRM Analysis Settings
Compound Nominal Mass Collision offset Dwell time
Q1 Q3 (eV) (ms)
DCDQ 229 186 22 300
ds-DCDQ 237 194 22 .300
(plasma only)
DCDQ carbamoyl 449 273 25 300
glucuronide
Data Analysis and Statistical Evaluation
The computer program Microsoft Excel® 97 was used to calculate means and standard
deviations and to perform the student f-test. Xcalibur (version 1.3) and MassLynx
software (version 4.0) were used for collection and analysis of LC/MS data. Peak area
ratios of M6 to the internal standard were used for quantitation of M6 in plasma samples.
RESULTS
Metabolite Profiles and M6 Concentrations in Plasma
DCDQ and eight DCDQ metabolites were identified in human plasma (Table 33). DCDQ
carbamoyl glucuronide (M6) was the predominant drug-related component in plasma in
all dose groups in both single and multiple dose studies. DCDQ imine N-oxide (M5),
unchanged DCDQ, DCDQ imine (P3) and trace amounts of hydroxyl DCDQ, hydroxyl
DCDQ imine, hydroxyl DCDQ glucuronide (M9) and keto DCDQ glucuronide (M22) were
also observed in plasma. Metabolite profiles were qualitatively similar in all samples
analyzed.
Plasma M6 concentrations increased with increased dosage, and large individual
variations were observed (Table 34). Of the three time points analyzed, M6
concentrations were the highest at 6 hour post-dose and decreased over time at 12 and
24 hour post-dose. The ratios of M6 to DCDQ plasma concentrations were also the
highest at 6 hour post-dose, and in general decreased over time. At 6 hour post-dose,
the average ratios ranged from 35.4 to 76.6. There were no statistically significant
differences in M6 concentrations and the M6 to DCDQ ratios between fasted and fed
subjects receiving 300 mg of DCDQ.
Metabolite Profiles and M6 to DCDQ Ratios in Urine
DCDQ and several DCDQ metabolites were identified in urine. DCDQ carbamoyl
glucuronide (M6) was the predominant drug-related component in urine, as in plasma.
Unchanged DCDQ, DCDQ N-oxide glucuronide (M40), hydroxyl DCDQ glucuronide
(M38), hydroxyl DCDQ carbamoyl glucuronide (M37) and trace amounts of DCDQ imine
(P3), hydroxyl DCDQ (M1 and M32), hydroxyl DCDQ imine (M29), keto DCDQ
glucuronide (M22), hydroxyl DCDQ glucuronide (M9), hydroxyl DCDQ carbamoyl
glucuronides (M33, M36 and M39), DCDQ imine glucuronide (M34) and dihydroxyl
DCDQ imine glucuronide (M35) were also observed in urine.
The carbamoyl glucuronide (M6) was present in urine at much higher concentrations
than the parent drug (Table 35). The average M6 to DCDQ ratios ranged from 84 to
1018; large variations were observed. The ratios appeared to he lower in the 500 mg
dosage group than in the other dose groups.
Metabolite Characterization by Liquid Chromatography/Mass Spectrometry
Mass spectra were obtained by LC/MS and LC/MS/MS analysis for DCDQ and its
metabolites in human plasma and urine. Table 33 summarizes the DCDQ metabolites
characterized in this study. As M6 (DCDQ carbamoyl glucuronide} was the predominant
DCDQ related component in both plasma and urine, and the relative concentration of
unchanged DCDQ was relatively minor. Therefore, mass spectral characterization o/ily
of DCDQ related components present in approximately equal or greater concentrations
than unchanged DCDQ in plasma or urine are discussed in more detail below.
DCDQ
The mass spectral characteristics of DCDQ authentic standard were examined for
comparison with metabolites. In the LC/MS spectrum of DCDQ, a protonated molecular
ion, [M+Hf, was observed at m/z 229. Loss of NH3 from [M+H]+ yielded m/z 212. Loss
of methyleneamine, ethylideneamine and propylideneamine from the molecular ion
generated the product ions at m/z 200,186 and 171, respectively. Loss of the propene
group from the molecular ion generated m/z 187 and further loss of methyleneamine and
ethylideneamine yielded m/z 158 and 144. Loss of cyclopentene from [M+H]+ yielded
m/z 161. Loss of the cyclopentyl-methyleneamine group generated the product ion at
m/z 132. •
Metabolite M5
Metabolite M5 produced a [M+H]+ at m/z 243, which was 14 Da larger than DCDQ and
16 Da larger than P3. These data suggested that M5 was a keto DCDQ metabolite,
hydroxyl DCDQ imine or DCDQ imine N-oxide. Loss of NH3 and H2O from [M+H]+
yielded m/z 226 and 225, respectively, which was consistent with addition of an oxygen
atom. Loss of methyleneamine, from the molecular ion was proposed to generate m/z
213, consistent with addition of oxygen and the presence of a double bond from loss of
two hydrogens. The product ion at m/z 130 was also observed for P3 and was 2 Da
less than the corresponding ion at m/z 132 for DGDQ. These data indicated that Mralso
contained an imine group, which eliminated keto DCDQ from consideration. The
HPLC retention time of M5 was longer than both DCDQ and P3 (DCDQ imine), which
was also observed in the in vitro metabolism study1 and consistent with N-oxidation.
Therefore, MS was identified as DCDQ imine N-oxide.
Metabolite M6
The [M+H]* fof M6 Was observed at m/z 449, which was 220 Da largerthan DCDQ.
Loss of 176 Da from the molecular ion generated m/z 273, indicating that M6 was a
glucuronide. Further loss of 44 Da from m/z 273 yielded m/z 229, which was also the
molecular ion for DCDQ. Product ions at m/z 212 and 186 were also observed for
DCDQ, consistent with M6 being a conjugate of DCDQ. Therefore, M6 was identified as
the carbamoyl glucuronide of DCDQ.
Metabolite M38
The [M+H]* for M38 was observed at m/z 421, which was 192 Da larger than DCDQ.
Loss of NH3 from [M+H]+ yielded m/z 404, which suggested an unchanged amino group
on the diazepane ring. Loss of 176 Da from the molecular ion generated m/z 245, which
was also the molecular ion for hydroxyl DCDQ metabolites. Losses of NH3 and H2O
from m/z 245 generated m/z 228 and 227, respectively. These data indicated that M38
was a glucuronide of a hydroxyl DCDQ. The product ion at m/z 362 was 176 Da larger
than the corresponding ion at m/z 186 for DCDQ, which indicated glucuronidation of the
quinoline-cyclopentane moiety. Product ions at m/z 362 and 269 were proposed to
include the glucuronic acid moiety and have been the result of fragmentation of
diazepine, quinoline and cyclopentane rings as indicated in the fragmentation scheme.
These data were consistent with glucuronidation of the quinoline nitrogen and
hydroxylation of the diazepine ring. Therefore M38 was identified as a hydroxyl DCDQ
glucuronide.
Metabolite M40
The IM+H]* for M40 was observed at m/z 421, which was 192 Da larger than DCDQ.
Loss of H2O from [M+H]+ yielded m/z 403. No apparent loss of NH3 was observed from
[M+H]*, which suggested a modified amino group on the diazepane ring. Loss of 176 Da
from the molecular ion generated m/z 245, which was also the molecular ion for hydroxyl
DCDQ metabolites. However, the relative intensity m/z 245 for M40 was weaker than
was observed for metabolite M38. Loss of an oxygen atom from m/z 245 yielded m/z
229, also the molecular ion for DCDQ. These data in combination with the presence of
m/z 229.as the base peak in the ion trap mass spectrum, rather than m/z 245 as was
observed for metabolite M38, indicated the presence of an N-oxide. Product ions at m/z
228, 227, 212 and* 1^10 respectively were generated by losses of H2O a>ri3"NH3 from m/z
245 and 229 as indicated in the fragmentation scheme. The HPLC retention time of M40
was longer than for M38, which was also consistent with M40 being an N-oxide. Product
ions at m/z 200 and 186 were also observed for DCDQ and were proposed to be the
result of loss of an oxygen atom from the corresponding N-oxide product ions for M40.
Product ions at m/z 360 and 271 were proposed to include the glucuronic acid moiety
and have been the result of fragmentation of diazepine, quinoline and cyclopentane
rings as indicated in the fragmentation scheme. These data were consistent with
glucuronidation of the amino group of the diazepine ring and N-oxidation of the quinoline
nitrogen. Therefore, M40 was proposed to be a DCDQ N-oxide glucuronide.
Discussion
DCDQ underwent metabolism in humans. DCDQ carbamoyl glucuronide (M6) was the
predominant drug-related component in both plasma and urine. DCDQ imine N-oxide
(M5), unchanged DCDQ, DCDQ imine (P3) were the other major drug-related
components observed in plasma. Unchanged DCDQ, DCDQ N-oxide glucuronide
(M40), hydroxyl DCDQ glucuronide (M38), hydroxyl DCDQ carbamoyi glucuronide (M37)
were excreted in urine.
Plasma M6 concentrations increased with increased dosage, and large individual
variations were observed. M6 concentrations decreased over time from 6 to 24 hour
post-dose. The ratios of M6 to DCDQ plasma concentrations were higher at 6 hour than
at 12 and 24 hour post-dose. At 6 hour post-dose, the average ratios ranged from 35.4
to 76.6. In contrast, much lower amounts of M6 were detected in the previous in vitro
and in vivo studies. There were no statistically significant differences in M6
concentrations and the M6 to DCDQ ratios between fasted and fed subjects receiving
300 mg of DCDQ. The average M6-to-DCDQ ratios ranged from 84 to 1018 in urine.
In summary, DCDQ underwent both phase I and phase II metabolism in healthy human
subjects and carbamoyi glucuronidation was the major metabolic pathway. In contrast to
animal studies, formation of the carbamoyi glucuronide (M6) was the major metabolic
pathway in humans, and M6 was the predominant drug-related metabolite in human
plasma and urine.
(Table Removed)

a: DCDQ concentrations were determined by Bioanalytical with a validated assay for human
plasma.4 Concentrations of M6 were quantified by anon-validated LC/MS method in
Biotransformation using a standard curve generated with synthesized M6.
b: Standard deviation was not calculated;
(Table Removed)

c: NA, not analyzed because the plasma DCDQ tevel was below the level of quantitation.
a: DCDQ concentrations were determined by Bioanalytical with a validated
assay for human urine.5 Concentrations of M6 were quantified by an nonvalidated
LC/MS method in Biotransformation using a standard curve
generated with synthesized M6.
All references, including but not limited to articles, texts, patents, patent
applications, publications, and books, cited herein are hereby incorporated by
reference in their entirety. This application claims priority benefit of U.S. Provisional
Application Ser. No. 60/625,335 filed November 5,2004, the entire content of which
is incorporated by reference herein in its entirety.

WHAT IS CLAIMED IS:
1. A compound of formula I
2. (Figure Removed)
Iwherein:.
for each Rn and Rn', where n is 1 through 8:
each R" and Rn> is independently hydrogen, hydroxy, CH3C(O)-O, -OSO3H, or
R" and the corresponding Rn>, where n is 2, 3,4, 6, 7, or 8, taken together with
the carbon to which they are attached, form C=O; or
R" along with the corresponding Rn+1, where n is 1,2, 3,4, 5, or 7, taken
together form a double bond between the carbons to which they are attached, and
each corresponding Rn> and R(n+1)> is independently hydrogen, hydroxy, CH3C(O)-O,
wherein the nitrogen denoted with the symbol * can optionally form an Noxide;
X-Y is CH=N, CH=N(0), CH2N(O), C(O)NH or CR9HNR10;
(Figure Removed)

R is hydrogen, hydroxyl, or -OSO3H;
R10 is hydrogen, acetyl, -SO3H, -G, or-C(O)-OG;
2 is hydrogen, hydroxy, -OSO3H, or -O-G;
with the proviso that when Z is hydroxy, then either (a) one of R1, R2, R3, R4,
R5, R6, R7, R8, R9, and R10 is not hydrogen; or (b) X-Y is not CR9HNR10; and
with the further proviso that when X-Y is CHR9NR10, then at least one of Z, R1,
R2, R3, R4, R5, R6, R7, R8, R9, and R10 is not H;
or a pharmaceutically acceptable salt thereof.
2. A compound or salt according to claim 1, wherein at least one of Z and R1
through R8 is -OH.
3. A compound or salt according to claim 2, wherein X-Y is CR9HNR10.
4. A compound or salt according to claim 2, wherein R9 = R10 = H.
5. A compound or salt according to claim 4, wherein at least one of R7 and R8 is
6. A compound or salt according to claim 4, wherein R6 is -OH.
(Figure Removed)

7. A compound or salt according to claim 4, wherein at least one of R3 and R4 is
8. A compound or salt according to claim 4, wherein at least one of R1, R5, R8,
R7, and Z is-OH.
9. A compound or salt according to claim 2, where R9 is H and R10 is acetyl.
10. A compound or salt according to claim 9, wherein at least one of R7 and RB is
11. A compound or salt according to claim 2, wherein X-Y is CH=N.
12. A compound or salt according to claim 11, wherein at least one of R1 through
13. A compound or salt according to claim 11, wherein at least one of R2 through
R4 is -OH.
14. A compound or salt according to claim 1, wherein
at least one of R1 through R6, R9, R10, and Z is -C(0)-O-G, -O-G, or -G.
15. A compound or salt according to claim 14, wherein X-Y is CR9HNR10.
16. A compound or salt according to claim 15, where R9 and R10 are H.
17. A compound or salt according to claim 15, wherein at least one of Z, R3, and
R4 is-O-G.
18. A compound or salt according to claim 14, wherein at least one of R1 through
R6, R9, and Z is -O-G.
19. A compound or salt according to claim 14, wherein R2 along with R3 taken
together form a double bond between the carbons to which they are attached, and at
least one of R3'and R4 is-O-G.
20. A compound or salt according to claim 15, wherein R4 and R4' together with
the carbon to which they are attached form C=O.
21. A compound or salt according to claim 20 wherein R10 is -G.
22. A compound or salt according to claim 15, where R10 is -C(O)O-G.
23. A compound or salt according to claim 15, where R10 is acetyl.
24. A compound or salt according to claim 23, wherein at least one of R1 through
R6, R9, and Z is -O-G.
25. A compound or salt according to claim 23, wherein at least one of R7 and R8
26. A compound or salt according to claim 1, wherein at least one of R1 through
R, and Z is-OSO3H.
27. A compound or salt according to claim 26, wherein X-Y is -CHR9NR10.
28. A compound or salt according to claim 26 or claim 27, where R9 = R10 = H.
29. A compound or salt according to claim 28, wherein at least one of R1 through
R6is-OSO3H.
30. A compound or salt according to claim 28, wherein at least one of R2 and R3
31. A compound or salt according to claim 28, wherein R3 is -OSO3H.
32. A compound or salt according to claim 26 or claim 27, wherein at least one of
R9andZis-OSO3H.
33. A compound or salt according to claim 1, wherein X-Y is CR9HNR10, where R9
is H and R10 is -SO3H.
34. A compound or salt according to claim 33, wherein at least two of Rn and the
corresponding R"1, where n = 1-5, form a double bond between the carbons to
which they are attached.
35. A compound or salt according to claim 1, wherein Rn and corresponding Rn
taken together with the carbon to which they are attached form C=O.
36. A compound or salt according to claim 35, wherein R4 and R4> taken together
with the carbon to which they are attached form C=O.
37. A compound or salt according to claim 36, wherein X-Y is CR9HNR10.
38. A compound or salt according to claim 36 or claim 37, wherein R10 is -G.
39. A compound or salt according to claim 36 or claim 37, where R9 and R10 are
40. A compound or salt according to claim 1, wherein X-Y is C(O)NH.
41. A compound or salt according to claim 1, wherein X-Y is CH=N.
42. A compound or salt according to claim 41, wherein at least one of R1 through
43. A compound c, salt according to claim 42, wherein at least one of R2 through
R4 is -OH.
44. A compound or salt according to claim 42 wherein the nitrogen between R6
and R7 forms an N-oxide.
45. A compound or salt according to claim 1, wherein at least one of R" and its
corresponding R"*1, where n = 1-5, together form a double bond between the
carbons to which they are attached and each R"' and R(n+1)> is independehtly
hydrogen, hydroxy, CH3C(O)-O, -OS03H, or-O-G.
46. A compound or salt according to claim 45, wherein n=2.
47. A compound or salt according to claim 45, wherein R2" - H, and R3' or R4 is
48. A compound or salt according to claim 45, wherein X-Y is CHR9NR10.
49. A compound or salt according to claim 48, wherein R9 = R10 = H.
50. A compound or salt according to claim 45, wherein for at least two R", each
said R" and its corresponding R"*1, where n = 1-5, together form a double bond
between the carbons to which they are attached.
51. A compound or salt according to claim 50, wherein X-Y = CHR9NR10.
52. A compound or salt according to claim 51, wherein R10 is H; and Z or R9 is -
OS03H.
53. A compound or salt according to claim 50, wherein R9 = R10 = H.
54. A compound or salt of claim 45, wherein R9 is H and R10 is -SO3H.
(Figure Removed)

55. A compound or salt of claim 45, wherein R9 is H and R10 is acetyl.
56. A method of preparing a compound of formula M6:
(Figure Removed)

comprising:
reacting Compound 6a:
2 6a
where each L, L1, and L2 is a leaving group;
with DCDQ:
in the presence of a coupling reagent under conditions sufficient to
yield compound 7:
(Figure Removed)

removing said leaving groups L1 and L2.
57. The method of claim 56 wherein L has the formula:
58. The method fo claim 56 wherin L1 and L2 are independently selected from
lower alkyl and acetyl.
59. The method of claim 56 wherein L1 is methyl and each L2 is acetyl.
60. The method of claim 56 further comprising:
deprotecting compound 7 by removing the L1 and L2 protecting groups of the
glucuronyl moiety of compound 7, thereby forming the M6 metabolite.
61. The method of claim 56 wherein said coupling reagent is selected from BOP,
DCC, and EDO.
62. The method of claim 56 wherein said couplingi reagent is BOP.
63. The method of claim 56 wherein said reaction of compound 6 with said
coupling reagent and DCDQ is carried out in the presence of an amine.
64. The method of claim 63 wherein said amine is HGnig's base.
65. The method of claim 63 wherein said reaction of compound 6 with said
coupling reagent and DCDQ is performed in a solvent.
66. The method of claim 65 wherein the solvent is CH2CI2.
67. The method of claim 60, wherein said compound 7 is subjected to column
chromatography purification prior to deprotection.
68. Thb method of claim 60, wherein said deprotecting is performed in alcohol in
the presence of a base.
69. The method of claim 68, wherein said base is selected from NaOH, LiOH, and
(Figure Removed)

70. The method of claim 68 wherein said alcohol is a lower alkyl alcohol.
71. The method of claim 68, wherein said deprotecting is performed with
LiOH.H20 in MeOH/H20/THF.
72. The method of claim 71, wherein said MeOH/H2O/THF ratio is approximately
2.5:1.0:0.5.
73. The method of claim 71 wherein said deprotection is carried out at 0 °C for 1
hour.
74. The method of claim 60 further comprising purifying said M6 metabolite.
75. The method of claim 57 wherein compound 6a is prepared by removing the
allyl protecting group of compound 5:
using a catalyst and a nucleophile.
76. The method of claim 75, wherein said catalyst is Pd(PPh3)4.
77. The method of claim 75, wherein said nucleophile is morpholine.
78. The method of claim 75, wherein compound 5 is prepared by:
reacting carboxylic acid 2:
with DPPA under conditions sufficient to yield an acyl azide intermediate;
heating resultant acyl azide intermediate under conditions sufficient to yield
isocyanate 3:
treating result of said heating step with 2,3,4,-triacetyl-l-hydroxyglucoronic
(Figure Removed)

under conditions sufficient to yield compound 5.
79. The method of claim 78, wherein said reacting step is carried out in the
presence of a base.
80. The method of claim 79, wherein said base is Et3N.
81. The method of claim 78, wherein compound 2 is prepared by reacting
diphenic anhydride with excess allyl alcohol in the presence of a catalyst.
82. The method of claim 81, wherein sajd allyl alcohol is prop-2-en-1-ol.
83. The method of claim 81 wherein said catalyst is DMAP.
84. A compound selected from the group consisting of:
(Figure Removed)

or a pharmaceutically acceptable salt thereof.
85. A pharmaceutical composition comprising a compound or salt of claim 84.
86. A compound selected from the group consisting of:
(Figure Removed)

or a pharmaceutically acceptable salt thereof.
87. A pharmaceutical composition comprising a compound or salt of claim
88. A compound selected from the group consisting of
(Figure Removed)

or a pharmaceutically acceptable salt thereof.
89. A pharmaceutical composition comprising a compound or salt of claim
90. A compound selected from the group consisting of:
(Figure Removed)

or a pharmaceutically acceptable salt thereof.
90.
91. A pharmaceutical composition comprising a compound or salt of claim
92. A compound selected from the group consisting of:
or a pharmaceutically acceptable salt thereof.
92.
93. A pharmaceutical composition comprising a compound or salt of claim
94. A compound selected from the group consisting of:
(Figure Removed)

or a pharmaceutically acceptable salt thereof.
94.
95. A pharmaceutical composition comprising a compound or salt of claim
96. A compound selected from the group consisting of:
or a pharmaceutically acceptable salt thereof.
(Figure Removed)

97. A pharmaceutical composition comprising a compound or salt of claim
98. A composition comprising a compound or salt according to any one of
claims 1 to 55, and one or more pharmaceutically acceptable carriers.
99. A method for treating a patient suffering from schizophrenia,
schizophreniform disorder, schizoaffective disorder, delusional disorder, substanceinduced
psychotic disorder, L-DOPA-induced psychosis, psychosis associated with
Alzheimer's dementia, psychosis associated with Parkinson's disease, psychosis
associated with Lewy body disease, dementia, memory deficit, or intellectual deficit
disorder associated with Alzheimer's disease comprising administering to the patient
a therapeutically effective amount of a compound or salt according to claim 1 or a
composition comprising such a compound or salt.
100. The method of claim 99, wherein the patient is suffering from
schizophrenia.
101. A method for treating a patient suffering from bipolar disorders,
depressive disorders, mood episodes, anxiety disorders, adjustment disorders, or
eating disorders comprising administering to the patient a therapeutically effective
amount of a compound or salt according to claim 1 or a composition comprising such
a compound or salt.
102. The method of claim 101, wherein the bipolar disorder is bipolar I
disorder, bipolar II disorder, or cyclothymic disorder; the depressive disorder is major
depressive disorder, dysthymic disorder, or substance-induced mood disorder; the
mood episode is major depressive episode, manic episode, mixed episode, or
hypomanic episode; the anxiety disorder is panic attack, agoraphobia, panic disorder,
specific phobia, social phobia, obsessive compulsive disorder, posttraumatic stress
disorder, acute stress disorder, generalized anxiety disorder, separation anxiety
disorder, or substance-induced anxiety disorder.
103. The method of claim 102, wherein the condition is depressive
disorder, bipolar disorder or mood episode.
104. A method for treating a patient suffering from epilepsy, sleep
disorders, migraines, sexual dysfunction, drug addiction, alcohol addiction,
gastrointestinal disorders, or obesity comprising administering to the patient a
therapeutically effective amount of a compound or salt according to claim 1 or a
composition cor. iprioing such a compound or salt.
105. A method for treating a patient suffering from a central nervous
system deficiency associated with trauma, stroke, or spinal cord injury comprising
administering to the patient a therapeutically effective amount of a compound or salt
according to claim 1 or a composition comprising such a compound or salt
106. A compound or salt according to claim 1, wherein Z, each Rn, and
each R"'is H; and X-Y is CR9HNR10.
107. A compound or salt according to claim 106, wherein R9 is H.
108. A compound or salt according to claim 106, wherein R9 is H and R10 is
109. A composition comprising a compound according to any one of claims
106 to 108, and one or more pharmaceutically acceptable carriers.
110. The Invention substantially such as herein before described.