MITOCHONDRIA-TARGETED DICARBONYL SEQUESTERING
COMPOUNDS
FIELD OF THE INVENTION
The invention relates to compounds and pharmaceutically acceptable salt5 s
thereof comprising a dicarbonyl sequestering moiety; an optional linker moiety;
and a mitochondrial targeting moiety. The invention also relates to
pharmaceutical compositions containing such compounds and salts, and to the
use of such compounds and salts for treating diabetes, preferably hyperglycaemic
10 diabetes. The invention also relates to the provision of a mass spectrometry
probe and to a method of labelling a biological molecule for mass spectrometry
detection.
BACKGROUND
15 Hyperglycaemia is a damaging medical condition. Hyperglycaemia wreaks its
effects via inappropriate glycation of molecules within cells. This glycation occurs
following generation of reactive 1,2-dicarbonyls such as glyoxal and
methylglyoxal. These reactive species modify molecules in the cell and cause
negative pathology.
20
Glycation, the non-enzymatic formation of sugar-protein and sugar-nucleotide
adducts, plays a major role in disrupting cell function and causing tissue damage
in a range of pathologies such as diabetes, aging and neurodegeneration [1-3].
Glycation increases in response to the elevation of glucose that occurs in
25 unregulated diabetes and is a major cause of diabetic complications [4, 5]. Within
the cell excessive glucose can lead to molecular damage through the formation of
1,2-dicarbonyl compounds such as methylglyoxal from the triose phosphate
intermediates of glycolysis [1, 6] or from the metabolism of acetone generated
during ketosis [7]. These reactive 1,2-dicarbonyls often exist in modified chemical
30 forms in situ including reversible hemiacetals, hemithioacetals and hemiaminals
with small biomolecules and with reactive moieties on proteins and nucleic acids
[8, 9]. In addition they can react directly with free amine functions on proteins
and nucleic acids, thereby generating substantial permanent modifications such
as arginine-derived hydroimidazolones and lysine cross-links on proteins [10],
35 and guanine-derived imidazopurinones on DNA [11]. Such modifications are
thought to result in biochemical dysfunction by altering protein structure and
activity, and by inducing genomic mutations [2]. These markers of glycation
2
damage are elevated in many clinical samples from diabetic patients and also in
animal models of diabetes and aging [2,4,9,12,13], consistent with a contribution
from these reactions to cell damage and pathology. An important role for
methylglyoxal and glyoxal in pathology is further supported by the existence of
the glyoxalase enzyme system, which specifically degrades these two dicarbonyl5 s
[14]. Loss of the glyoxalase degradation pathway renders organisms more
susceptible to glycation and subsequent damage while its over-expression
increases lifespan in Caenorhabditis elegans [15]. Thus dicarbonyl-associated
glycation of proteins and nucleic acids is a significant contributing factor in a
10 range of pathologies, particularly those associated with diabetes or aging.
In hyperglycaemia, there is considerable evidence for mitochondrial damage and
elevated oxidative stress that contributes to pathology, and this has been in part
ascribed to mitochondrial glycation due to methylglyoxal and glyoxal [16-21].
15 Furthermore these reactive dicarbonyls disrupt mitochondrial function in vitro
[22-24]. Therefore, understanding the contribution from glycation damage by
reactive dicarbonyls to mitochondrial dysfunction is important for analyzing and
understanding the pathology associated with hyperglycaemia. However, the
mechanistic details are uncertain, and it has proven difficult to specifically
20 evaluate the importance of these processes. This is in part due to the
uncertainties related to the distribution of methylglyoxal and glyoxal between the
cytosol and mitochondria. In known approaches to combating the effects of
hyperglycaemia, it has been attempted to use reactive guanidine groups. This
forms a generalised “mopping” approach. The guanidine groups react with
25 glyoxal/methylglyoxal groups. However, this guanidine approach is entirely
untargeted. This is a drawback in the art.
SUMMARY
In addressing problem(s) associated with the prior art, the solution provided by
30 the inventors includes compounds of the invention which specifically target
molecular groups capable of sequestering the dicarbonyls that are found within
mitochondria under conditions of hyperglycaemia.
These compounds couple a targeting moiety to a sequestering moiety so that the
35 compounds preferentially accumulate in the mitochondria, where they are
maximally effective in reducing and/or preventing the damage caused by the
reactive dicarbonyls. Optionally, the sequestering moiety may be attached to the
3
targeting moiety via a linker moiety. It should be noted that the approach of
sequestering the reactive groups within mitochondria is new. This approach has
not been contemplated in any known treatment. It should be noted that the
approach underlying the invention of sequestering the reactive groups within
mitochondria themselves is a departure from known techniques. These and othe5 r
benefits flow from the invention as explained below.
Thus, in a broad aspect the invention relates to a compound of Formula 1:
10 A-L-B
Formula 1
or a pharmaceutically acceptable salt thereof, wherein:
A is a dicarbonyl sequestering moiety comprising a substituted aryl group
15 or a substituted heteroaryl group;
L is a linker moiety; and
B is a mitochondrial targeting moiety;
wherein the substituted aryl group, or the substituted heteroaryl group
20 comprises two or more substituent groups independently selected from -
OH,
-OR1, -NH2, -NHR1, -NR1R1, -1X-NH2, -1X-NHR1, -O-NH2, -O-NHR1, -1X-ONH2,
-1X-O-NHR1, -NR’-NHR’, -1X-NR’-NHR’, -NHCOR1 and -O-C(O)-R1; and
25
wherein the substituted aryl group, or the substituted heteroaryl group
may optionally comprise one or more optional substituent groups selected
from
-C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, -halogen, -1X-OH, -1X -O-R1, -CO2H,
30 -1X-CO2H, -CO2R1, -1X-CO2R1, -1X-O-C(O)-R1, -CH(OH)-C(O)-R1, -1XNR1R1,
-1X-CH(OH)-C(O)-R1, -CHO, -C(O)-R1, -C(O)NH2, -C(O)NHR1, -SO2NH2
and
-SO2NHR1; and
35
wherein
4
each R1 is independently selected from -C1-6 alkyl, -C2-6 alkenyl, -C2-6
alkynyl, and Formula 2
Formula 2
5
wherein each group R2-R6 is independently selected from –H, -C1-6 alkyl,
-C2-6 alkenyl, -C2-6 alkynyl, -halogen, -OH, -1X-OH, -O-C1-6 alkyl,
-1X-O-C1-6 alkyl, -NR’R’, -1X-NR’R’, -1X-NH-C1-6 alkyl, -O-NH2, -O-NH-C1-6
alkyl,
10 -1X -O-NH2, -1X-O-NH-C1-6 alkyl, -NR’-NHR’, -1X-NR’-NHR’,
-NHC(O)-C1-6 alkyl, -O-C(O)-C1-6 alkyl, -CO2H, -1X-CO2H, -CO2C1-6 alkyl,
-1X-CO2C1-6 alkyl, -1X-O-C(O)-C1-6 alkyl, -CH(OH)-C(O)-C1-6 alkyl, -CHO,
-C(O)-C1-6 alkyl, -1X-CH(OH)-C(O)-C1-6 alkyl, -C(O)NH2, -C(O)NH C1-6
alkyl,
15 -SO2NH2 and -SO2NH C1-6 alkyl;
each R’ is independently selected from –H and -C1-6 alkyl; and
each 1X is independently selected from C1-6 alkylene, C2-6 alkenylene and
20 C2-6 alkynylene.
In one aspect the invention provides a pharmaceutical composition which
comprises: a compound of Formula 1, as defined above, or a pharmaceutically
acceptable salt thereof, and a pharmaceutically acceptable excipient, carrier or
25 diluent.
A further aspect of the invention provides a compound of Formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use as a medicament.
30 A further aspect of the invention provides a compound of Formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use in the treatment of
diabetes, preferably hyperglycaemic diabetes.
5
A further aspect of the invention provides a compound of Formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for the preparation of a
medicament for the treatment of diabetes, preferably hyperglycaemic diabetes.
A further aspect of the invention provides a method of treating a disease o5 r
condition in a subject, the method comprising administering to the subject an
effective amount of a compound of Formula 1, as defined above, or a
pharmaceutically acceptable salt thereof, wherein the disease or condition is
diabetes, preferably hyperglycaemic diabetes.
10
A further aspect of the invention provides a compound of formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use in the preservation of
organ and tissue for surgical transplants.
15 A further aspect of the invention provides a compound of formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use in the storage of blood.
A further aspect of the invention provides a compound of formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use in the prevention or
20 treatment of hyperglycaemia.
A further aspect of the invention provides a compound of Formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use as a mass spectrometry
probe.
25
A further aspect of the invention provides a method of labelling a biological
molecule for mass spectrometry detection comprising contacting said molecules
with a compound of formula 1 or a pharmaceutically acceptable salt thereof.
30 DETAILED DESCRIPTION OF THE INVENTION
“Substituted”, when used in connection with a chemical substituent or moiety
(e.g., an alkyl group), means that one or more hydrogen atoms of the substituent
or moiety have been replaced with one or more non-hydrogen atoms or groups,
provided that valence requirements are met and that a chemically stable
35 compound results from the substitution.
6
“Alkyl” refers to straight chain and branched saturated hydrocarbon groups,
generally having a specified number of carbon atoms (e.g., C1-3 alkyl refers to an
alkyl group having 1 to 3 carbon atoms, C1-6 alkyl refers to an alkyl group having 1
to 6 carbon atoms, and so on). Examples of alkyl groups include methyl, ethyl, npropyl,
i-propyl, n-butyl, s-butyl, i-butyl, t-butyl, pent-1-yl, pent-2-yl, pent-3-yl5 ,
3-methylbut-1-yl, 3-methylbut-2-yl, 2-methylbut-2-yl, 2,2,2-trimethyleth-1-yl, nhexyl,
and the like.
“Alkylene” refers to a divalent radical derived from an alkane which may be a
10 straight chain or branched, as exemplified by –CH2CH2CH2CH2-.
The terms “cycloalkyl” by itself or in combination with other terms, represent,
unless otherwise stated, a cyclic versions of “alkyl”. Examples of cycloalkyl
include cyclopentyl, cyclohexyl, 1-cyclohexenyl, 3-cyclohexenyl, cycloheptyl, and
15 the like.
The term “alkenyl”, as used herein, means a hydrocarbon radical having at least
one double bond including, but not limited to, ethenyl, propenyl, 1-butenyl, 2-
butenyl and the like.
20
The term “alkenylene” refers to a divalent radical derived from an alkenyl which
may be a straight chain or branched, containing one or more double bonds, as
exemplified by,
-CH2CH=CH-, or -CH2CH(CH3)CH=CH-CH2-.
25
The term “alkynyl”, as used herein, means a hydrocarbon radical having at least
one triple bond including, but not limited to, ethynyl, propynyl, 1-butynyl, 2-
butynyl and the like.
30 The term “alkynylene” refers to a divalent unsaturated hydrocarbon group which
may be linear or branched, containing one or more carbon-carbon triple bonds,
as exemplified by, ethyne- 1,2-diyl.
“Aryl” employed alone or in combination with other terms (e.g., aryloxy,
35 arylthioxy, arylalkyl) refers to fully unsaturated monocyclic aromatic
hydrocarbons and to polycyclic hydrocarbons having at least one aromatic ring,
both monocyclic and polycyclic aryl groups generally having a specified number
7
of carbon atoms that comprise their ring members (e.g., C6-14 aryl refers to an aryl
group having 6 to 14 carbon atoms as ring members). The aryl group may be
attached to a parent group or to a substrate at any ring atom and may include one
or more non-hydrogen substituents unless such attachment or substitution would
violate valence requirements. Examples of aryl groups include phenyl, biphenyl5 ,
cyclobutabenzenyl, indenyl, naphthalenyl, benzocycloheptenyl, biphenylenyl,
fluorenyl, groups derived from cycloheptatriene cation, and the like.
“Arylene” refers to a divalent radical derived from an aryl group.
10
The term “alkoxy”, as used herein, means an O-alkyl group wherein “alkyl” is
defined above.
The term “aralkyl” or “arylalkyl” means an aryl-alkyl- group in which the aryl and
15 alkyl are as previously described. Preferred aralkyls comprise a lower alkyl group
attached to the aryl group. Non-limiting examples of suitable aralkyl groups
include phenymethylene, 2-phenethyl and naphthalenylmethyl. The bond to the
parent moiety is through the alkyl.
20 “Cycloalkyl” refers to saturated monocyclic and bicyclic hydrocarbon groups,
generally having a specified number of carbon atoms that comprise the ring or
rings (e.g., C3-8 cycloalkyl refers to a cycloalkyl group having 3 to 8 carbon atoms
as ring members). Bicyclic hydrocarbon groups may include isolated rings (two
rings sharing no carbon atoms), spiro rings (two rings sharing one carbon atom),
25 fused rings (two rings sharing two carbon atoms and the bond between the two
common carbon atoms), and bridged rings (two rings sharing two carbon atoms,
but not a common bond). The cycloalkyl group may be attached to a parent group
or to a substrate at any ring atom unless such attachment would violate valence
requirements. In addition, the cycloalkyl group may include one or more non30
hydrogen substituents unless such substitution would violate valence
requirements.
Examples of monocyclic cycloalkyl groups include cyclopropyl, cyclobutyl,
cyclopentyl, cyclohexyl, and the like. Examples of fused bicyclic cycloalkyl groups
35 include bicyclo[2.1.0]pentanyl (i.e., bicyclo[2.1.0]pentan-1-yl,
bicyclo[2.1.0]pentan-2-yl, and bicyclo[2.1.0]pentan-5-yl), bicyclo[3.1.0]hexanyl,
bicyclo[3.2.0]heptanyl, bicyclo[4.1.0]heptanyl, bicyclo[3.3.0]octanyl,
8
bicyclo[4.2.0]octanyl, bicyclo[4.3.0]nonanyl, bicyclo[4.4.0]decanyl, and the like.
Examples of bridged cycloalkyl groups include bicyclo[2.1.1]hexanyl,
bicyclo[2.2.1]heptanyl, bicyclo[3.1.1]heptanyl, bicyclo[2.2.2]octanyl,
bicyclo[3.2.1]octanyl, bicyclo[4.1.1]octanyl, bicyclo[3.3.1]nonanyl,
bicyclo[4.2.1]nonanyl, bicyclo[3.3.2]decanyl, bicyclo[4.2.2]decanyl5 ,
bicyclo[4.3.1]decanyl, bicyclo[3.3.3]undecanyl, bicyclo[4.3.2]undecanyl,
bicyclo[4.3.3]dodecanyl, and the like. Examples of spiro cycloalkyl groups include
spiro[3.3]heptanyl, spiro[2.4]heptanyl, spiro[3.4]octanyl, spiro[2.5]octanyl,
spiro[3.5]nonanyl, and the like. Examples of isolated bicyclic cycloalkyl groups
10 include those derived from bi(cyclobutane), cyclobutanecyclopentane,
bi(cyclopentane), cyclobutanecyclohexane, cyclopentanecyclohexane,
bi(cyclohexane), etc.
“Drug”, “drug substance”, “active pharmaceutical ingredient”, and the like, refer
15 to a compound (e.g., compounds of Formula 1 and compounds specifically named
above) that may be used for treating a subject in need of treatment.
“Excipient” refers to any substance that may influence the bioavailability of a
drug, but is otherwise pharmacologically inactive.
20
“Halo”, “halogen” and “halogeno” may be used interchangeably and refer to
fluoro, chloro, bromo, and iodo. Additionally, terms such as “fluoroalkyl”, are
meant to include monofluoroalkyl and polyfluoroalkyl.
25 “Heteroaryl” refers to unsaturated monocyclic aromatic groups and to polycyclic
groups having at least one aromatic ring, each of the groups having ring atoms
composed of carbon atoms and 1 to 4 heteroatoms independently selected from
nitrogen, oxygen, and sulfur. Both the monocyclic and polycyclic groups generally
have a specified number of carbon atoms as ring members (e.g., C1-9 heteroaryl
30 refers to a heteroaryl group having 1 to 9 carbon atoms and 1 to 4 heteroatoms as
ring members) and may include any bicyclic group in which any of the abovelisted
monocyclic heterocycles are fused to a benzene ring. The heteroaryl group
may be attached to a parent group or to a substrate at any ring atom and may
include one or more non-hydrogen substituents unless such attachment or
35 substitution would violate valence requirements or result in a chemically unstable
compound. Examples of heteroaryl groups include monocyclic groups such as
pyrrolyl (e.g., pyrrol-1-yl, pyrrol-2-yl, and pyrrol-3-yl), furanyl, thiophenyl,
9
pyrazolyl, imidazolyl, isoxazolyl, oxazolyl, isothiazolyl, thiazolyl, 1,2,3-triazolyl,
1,3,4-triazolyl, 1-oxa-2,3-diazolyl, 1-oxa-2,4-diazolyl, 1-oxa-2,5-diazolyl, 1-oxa-
3,4-diazolyl, 1-thia-2,3-diazolyl, 1-thia-2,4-diazolyl, 1-thia-2,5-diazolyl, 1-thia-
3,4-diazolyl, tetrazolyl, pyridinyl, pyridazinyl, pyrimidinyl, and pyrazinyl.
5
Examples of heteroaryl groups also include bicyclic groups such as benzofuranyl,
isobenzofuranyl, benzothiophenyl, benzo[c]thiophenyl, indolyl, 3H-indolyl,
isoindolyl, 1H-isoindolyl, indolinyl, isoindolinyl, benzimidazolyl, indazolyl,
benzotriazolyl, chromanyl, 2-phenylchromanyl, 3-phenylchromanyl, 4-
10 phenylchromanyl, chromen-4-only, 2-phenylchromen-4-only, 3-phenylchromen-
4-only, coumarinyl, 3-phenylcoumarinyl, 4-phenylcoumarinyl, 1,8-bis[2-
chromanyl]-6-benzo[7]annuleonyl, 1H-pyrrolo[2,3-b]pyridinyl, 1H-pyrrolo[2,3-
c]pyridinyl, 1H-pyrrolo[3,2-c]pyridinyl, 1H-pyrrolo[3,2-b]pyridinyl, 3Himidazo[
4,5-b]pyridinyl, 3H-imidazo[4,5-c]pyridinyl, 1H-pyrazolo[4,3-
15 b]pyridinyl, 1H-pyrazolo[4,3-c]pyridinyl, 1H-pyrazolo[3,4-c]pyridinyl, 1Hpyrazolo[
3,4-b]pyridinyl, 7H-purinyl, indolizinyl, imidazo[1,2-c]pyridinyl,
imidazo[1,5-c]pyridinyl, pyrazolo[1,5-c]pyridinyl, pyrrolo[1,2-b]pyridazinyl,
imidazo[1,2-c]pyrimidinyl, quinolinyl, isoquinolinyl, cinnolinyl, quinazolinyl,
quinoxalinyl, phthalazinyl, 1,6-naphthyridinyl, 1,7-naphthyridinyl, 1,8-
20 naphthyridinyl, 1,5-naphthyridinyl, 2,6-naphthyridinyl, 2,7-naphthyridinyl,
pyrido[3,2-c]pyrimidinyl, pyrido[4,3-c]pyrimidinyl, pyrido[3,4-c]pyrimidinyl,
pyrido[2,3-c]pyrimidinyl, pyrido[2,3-b]pyrazinyl, pyrido[3,4-b]pyrazinyl,
pyrimido[5,4-c]pyrimidinyl, pyrazino[2,3-b]pyrazinyl, and pyrimido[4,5-
c]pyrimidinyl.
25
“Heterocycle” and “heterocyclyl” may be used interchangeably and refer to
saturated or partially unsaturated monocyclic or bicyclic groups having ring
atoms composed of carbon atoms and 1 to 4 heteroatoms independently selected
from nitrogen, oxygen, and sulfur. Both the monocyclic and bicyclic groups
30 generally have a specified number of carbon atoms in their ring or rings (e.g., C2-
5 heterocyclyl refers to a heterocyclyl group having 2 to 5 carbon atoms and 1 to 4
heteroatoms as ring members). As with bicyclic cycloalkyl groups, bicyclic
heterocyclyl groups may include isolated rings, spiro rings, fused rings, and
bridged rings. The heterocyclyl group may be attached to a parent group or to a
35 substrate at any ring atom and may include one or more non-hydrogen
substituents unless such attachment or substitution would violate valence
requirements or result in a chemically unstable compound. Examples of
10
monocyclic heterocyclyl groups include oxiranyl, thiaranyl, aziridinyl (e.g.,
aziridin-1-yl and aziridin-2-yl), oxetanyl, thiatanyl, azetidinyl, tetrahydrofuranyl,
tetrahydrothiophenyl, pyrrolidinyl, tetrahydropyranyl, tetrahydrothiopyranyl,
piperidinyl, 1,4-dioxanyl, 1,4-oxathianyl, morpholinyl, 1,4-dithianyl, piperazinyl,
1,4-azathianyl, oxepanyl, thiepanyl, azepanyl, 1,4-dioxepanyl, 1,4-oxathiepanyl5 ,
1,4-oxaazepanyl, 1,4-dithiepanyl, 1,4-thiazepanyl, 1,4-diazepanyl, 3,4-dihydro-
2H-pyranyl, 5,6-dihydro-2H-pyranyl, 2H-pyranyl, 1,2,3,4-tetrahydropyridinyl,
and 1,2,5,6-tetrahydropyridinyl
10 “Pharmaceutically acceptable” substances refers to those substances which are
within the scope of sound medical judgment suitable for use in contact with the
tissues of subjects without undue toxicity, irritation, allergic response, and the
like, commensurate with a reasonable benefit-to-risk ratio, and effective for their
intended use.
15
“Pharmaceutical composition” refers to the combination of one or more drug
substances and one or more excipients.
The term “sulfonyl” refers to a radical -S(O)2R where R is an alkyl, substituted
20 alkyl, substituted cycloalkyl, substituted heterocycloalkyl, substituted aryl, or
substituted heteroaryl group as defined herein. Representative examples include,
but are not limited to methylsulfonyl, ethylsulfonyl, propylsulfonyl, butylsulfonyl,
and the like.
25 The term “sulfinyl” refers to a radical -S(O)R where R is an alkyl, substituted
alkyl, substituted cycloalkyl, substituted heterocycloalkyl, substituted aryl, or
substituted heteroaryl group as defined herein. Representative examples include,
but are not limited to, methylsulfinyl, ethylsulfinyl, propylsulfinyl, butylsulfinyl,
and the like.
30
The term “subject” as used herein refers to a human or non-human mammal.
Examples of non-human mammals include livestock animals such as sheep,
horses, cows, pigs, goats, rabbits, deer, ostriches and emus; and companion
animals such as cats, dogs, rodents, and horses.
35
11
“Therapeutically effective amount” of a drug refers to the quantity of the drug that
may be used for treating a subject and may depend on the weight and age of the
subject and the route of administration, among other things.
“Treating” refers to reversing, alleviating, inhibiting the progress of, o5 r
preventing a disorder, disease or condition to which such term applies, or to
reversing, alleviating, inhibiting the progress of, or preventing one or more
symptoms of such disorder, disease or condition.
10 “Treatment” refers to the act of “treating”, as defined immediately above.
As used herein the term “comprising” means “consisting at least in part of”. When
interpreting each statement in this specification that includes the term
“comprising”, features other than that or those prefaced by the term may also be
15 present. Related terms such as “comprise” and “comprises” are to be interpreted
in the same manner.
DICARBONYL SEQUESTERING MOIETY
The dicarbonyl sequestering moiety A comprises a substituted aryl group or a
20 substituted heteroaryl group. A diacarbonyl sequestering moiety is a moiety that
forms a stable compound, such as a quinoxaline compound, with a dicarbonyl
molecule, suitably, with a 1,2-dicarbonyl molecule. The dicarbonyl sequestering
moiety is used to sequester dicarbonyl molecules in biological systems, such as
the dilute solutions found in cells. In order for the dicarbonyl sequestering
25 moiety to form a stable compound with a dicarbonyl molecule under the
conditions found in cells, the dicarbonyl sequestering moiety must be sufficiently
nucleophilic to form adducts spontaneously with the dicarbonyl molecule at low
concentrations in water at body temperature. In the dilute solutions of biological
systems, such as those found in cells, the first step to produce a stable compound
30 with a dicarbonyl compound is to form a hemiacetal, hemiaminal or
hemithioacetal which is a reversible reaction with the equilibrium in favour of the
starting materials.
Suitably the substituted aryl group, or the substituted heteroaryl group comprises
35 two or more substituent groups independently selected from -NH2, -NHR1, -
NR1R1,
-1X-NH2, -1X-NHR1, -O-NH2, -O-NHR1, -1X-O-NH2, -1X-O-NHR1, -NR’-NHR’,
12
-1X-NR’-NHR’ and -NHCOR1.
Suitably the substituted aryl group or substituted heteroaryl group comprises
from two to nine substituent groups. More suitably, the substituted aryl group or
substituted heteroaryl group comprises from two to eight substituent groups5 ;
from two to seven substituent groups; from two to six substituent groups; or from
two to five substituent groups.
Suitably the substituted aryl group or substituted heteroaryl group comprises
10 from two to nine substituent groups independently selected from -OH, -OR1, -
NH2, -NHR1,
-NR1R1, -1X-NH2, -1X-NHR1, -O-NH2, -O-NHR1, -1X-O-NH2, -1X-O-NHR1, -NR’-
NHR’,
-1X-NR’-NHR’, -NHCOR1 and -O-C(O)-R1.
15
Thus, the substituent groups may comprise hydrazine derivatives such as –NHNH2,
-NH-NH(C1-6 alkyl), -N(C1-6 alkyl)-NH2, -N(C1-6 alkyl)-NH(C1-6 alkyl), -1X-NH-NH2,
-1X-NH-NH(C1-6 alkyl),-1X-N(C1-6 alkyl)-NH2 and -1X-N(C1-6 alkyl)-NH(C1-6 alkyl).
20
Suitably the substituted aryl group, or the substituted heteroaryl group comprises
two or more substituent groups independently selected from -OH, -OR1, -NH2, -
NHR1,
-NR1R1, -1X-NH2, -1X-NHR1, -NHCOR1, and -O-C(O)-R1.
25
Suitably the substituted aryl group, or the substituted heteroaryl group comprises
two or more substituent groups independently selected from -NH2, -NHR1, -
NR1R1, -1X-NH2, -1X-NHR1 and -NHCOR1.
30 Suitably the substituted aryl group, or the substituted heteroaryl group comprises
two or more substituent groups independently selected from -OH, -OR1, -NH2, -
NHR1,
-NR1R1, -C1-6 alkylene-NH2, -C1-6 alkylene-NHR1, -NHCOR1, and -O-C(O)-R1.
35 More suitably the substituted aryl group, or the substituted heteroaryl group
comprises two or more substituent groups independently selected from -OH, -
OR1, -NH2 and
13
-C1-6 alkylene-NH2.
More suitably the substituted aryl group, or the substituted heteroaryl group
comprises two or more substituent groups independently selected from -NH2 and
-C1-6 alkylene-NH25 .
Suitably the substituted aryl group, or the substituted heteroaryl group comprises
from one to seven of the optional substituent groups; from one to six of the
optional substituent groups; from one to five of the optional substituent groups;
10 from one to four of the optional substituent groups; from one to three of the
optional substituent groups.
Suitably, the substituted aryl group, or the substituted heteroaryl group
comprises one or more of the optional substituent groups selected from-C1-6
15 alkyl, -C2-6 alkenyl,
-C2-6 alkynyl, -halogen, -1X-OH, -1X -O-R1, -CO2H, -1X-CO2H, -CO2R1, -1X-CO2R1,
-C(O)NH2, -C(O)NHR1, -SO2NH2 and -SO2NHR1.
Suitably, the substituted aryl group, or the substituted heteroaryl group
20 comprises one or more of the optional substituent groups selected from -C1-6
alkyl, -halogen,
-C1-6 alkylene-OH, -C1-6 alkylene-O-R1, -CO2H, -C1-6 alkylene-CO2H, -CO2R1,
-C1-6 alkylene-CO2R1, -C1-6 alkylene-O-C(O)-R1, -CHO and -C(O)-R1, -C(O)NH2,
-C(O)NHR1, -SO2NH2 and -SO2NHR1.
25
Suitably, the substituted aryl group, or the substituted heteroaryl group
comprises one or more of the optional substituent groups selected from -C1-6
alkyl, -halogen, -C1-6 alkylene-OH, -C1-6 alkylene-O-R1, -CO2H, -CO2R1.
30 More suitably, R1 is a -C1-6 alkyl. More suitably, R1 is selected from methyl, ethyl,
n-propy, i-propyl, n-butyl, s-butyl, i-butyl and t-butyl.
More suitably, R1 has the structure of Formula 2:
14
Formula 2
wherein each group R2-R6 is independently selected from –H, -C1-6 alkyl,
-halogen, -OH, -C1-6 alkylene-OH, -O-C1-6 alkyl, -C1-6 alkylene-O-C1-6 alkyl, 5 -
NH2,
-(C1-C6)alkylene-NH2, -CO2H and-CO2C1-6 alkyl.
More suitably, two or more of R2-R6 are –H.
10
More suitably, R2 and R6 are –H.
More suitably, R2 and R6 are –H and R3, R4 and R5 are –OH
15 Suitably, A is a dicarbonyl sequestering moiety comprising a substituted aryl
group selected from substituted phenyl, biphenyl and naphthalenyl; or a
substituted heteroaryl group selected from substituted pyrrolyl, furanyl,
thiophenyl, pyrazolyl, imidazolyl, pyridinyl, pyridazinyl, pyrimidinyl, chromanyl,
2-phenylchromanyl, 3-phenylchromanyl, 4-phenylchromanyl, chromen-4-only,
20 2-phenylchromen-4-only, 3-phenylchromen-4-only, coumarinyl, 3-
phenylcoumarinyl, 4-phenylcoumarinyl and 1,8-bis[2-chromanyl]-6-
benzo[7]annuleonyl.
More suitably, A is a dicarbonyl sequestering moiety comprising a substituted
25 aryl group selected from substituted phenyl and naphthalenyl; or a substituted
heteroaryl group selected from substituted pyridinyl, chromanyl, 2-
phenylchromanyl, 3-phenylchromanyl, 4-phenylchromanyl, chromen-4-only, 2-
phenylchromen-4-only, 3-phenylchromen-4-only, coumarinyl, 3-
phenylcoumarinyl, 4-phenylcoumarinyl and 1,8-bis[2-chromanyl]-6-
30 benzo[7]annuleonyl.
15
More suitably, A is a dicarbonyl sequestering moiety comprising a substituted
aryl group selected from substituted phenyl and naphthalenyl; or a substituted
heteroaryl group selected from substituted pyridinyl.
More suitably, the dicarbonyl sequestering moiety A is a substituted phenyl5 .
More suitably, the dicarbonyl sequestering moiety A is a substituted phenyl
comprising from two to five substituent groups; more suitably, from two to four
substituent groups; more suitably, from two to three substituent groups.
10
More suitably, the dicarbonyl sequestering moiety A is a substituted aryl group
comprising Formula 3:
Formula 3
15
wherein two or more of R7-R11 are independently selected from -OH, -OR1, -NH2,
-NHR1, -NR1R1, -C1-6 alkylene-NH2, -C1-6 alkylene-NHR1, -O-NH2, -O-NHR1,
-C1-6 alkylene-O-NH2, -C1-6 alkylene-O-NHR1, -NHCOR1, -O-C(O)-R1, -NR’-NHR’,
-C1-6 alkylene -NR’-NHR’; and
20
the remaining groups R7-R11 are independently selected from -H, -C1-6 alkyl,
-C2-6 alkenyl, -C2-6 alkynyl,-halogen, -C1-6 alkylene-OH, -C1-6 alkylene-O-R1,
-CO2H, -C1-6 alkylene-CO2H, -CO2R1, -C1-6 alkylene-CO2R1, -C1-6 alkylene-O-C(O)-
R1,
25 -CH(OH)-C(O)-R1, -C1-6 alkylene-CH(OH)-C(O)-R1, -CHO, -C(O)-R1, -C(O)NH2,
-C(O)NHR1, -SO2NH2 and -SO2NHR1.
More suitably two or more of R7-R11 are independently selected from -OH, -NH2,
-OC1-C6 alkyl, -NH(C1-C6 alkyl), -C1-C6alkylene-NH2, -C1-C6alkylene-NH(C1-C6
30 alkyl).
More suitably two or more of R7-R11 are independently selected from -OH,
-OC1-C6 alkyl, -NH2, -NH(C1-C6alkyl), -C1-C6 alkylene-NH2 and
16
-C1-C6 alkylene-NH(C1-C6 alkyl); and the remaining groups R7-R11 are
independently selected from –H, -C1-6 alkyl, -C1-6 alkylene-OH, -C1-6 alkylene-OC1-
6 alkyl, -CO2H,
-CO2C1-6 alkyl, -CH(OH)-C(O)-C1-6 alkyl and -CHO.
5
Suitably, from one to three of R7-R11 are–H.
More suitably two or more of R7-R11 is independently selected from -OH, -OC1-C6
alkyl, -NH2, -NH(C1-C6 alkyl), -C1-C6alkylene-NH2 and -C1-C6alkylene-NH(C1-C6
10 alkyl); and the remaining groups R7-R11 are independently selected from –H, -C1-6
alkyl,
-C1-6 alkylene-OH and -C1-6 alkylene-OC1-6 alkyl.
More suitably, R7 = -H, R10 = -H, and R11 = -H, and R8 and R9 are independently
15 selected from -OH, -OR1, -NH2, -NHR1, -C1-6 alkylene-NH2, -C1-6 alkylene-NHR1,
-O-NH2, -O-NHR1, -C1-6 alkylene-O-NH2, -C1-6 alkylene-O-NHR1, -NHCOR1 and
-O-C(O)-R1.
More suitably, R7 = -H, R10 = -H, and R11 = -H, and R8 and R9 are independently
20 selected from OH, -OC1-C6 alkyl, -NH2, -NH(C1-C6 alkyl), -C1-C6alkylene-NH2 and
-C1-C6 alkylene-NH(C1-C6 alkyl).
More suitably, R7 = -H, R10 = -H, and R11 = -H, and R8 and R9 are independently
selected from -OH, -C1-C6 alkylene-OH, -NH2 and -C1-C6 alkylene-NH2.
25
More suitably, R7 = -H, R8 = -NH2, R9 = -NH2, R10 = -H, and R11 = -H. This
results in a dicarbonyl sequestering moiety A of Formula 4:
Formula 4
30
In one aspect, the dicarbonyl sequestering moiety A comprises a substituted
flavonoid or theaflavin compound which comprises a heteroaryl group selected
from substituted chromanyl, 2-phenylchromanyl, 3-phenylchromanyl, 4-
17
phenylchromanyl, chromen-4-only, 2-phenylchromen-4-only, 3-phenylchromen-
4-only, coumarinyl, 3-phenylcoumarinyl, 4-phenylcoumarinyl and 1,8-bis[2-
chromanyl]-6-benzo[7]annuleonyl.
The trapping of species such as glyoxal and methylglyoxal with various flavonoi5 d
or theaflavin compounds have been described [55]-[57].
More suitably, the substituted flavonoid or theaflavin compound comprises one
or more substituent groups independently selected from -OH, -OR1, -NHCOR1
10 and
-O-C(O)-R1; and may optionally comprises one or more substituent groups
selected from -C1-6 alkyl, -halogen, -C1-6 alkylene-OH, -C1-6 alkylene-O-R1, -CO2H,
-CO2R1,
-CH(OH)-C(O)-R1 and -CHO, and
15 wherein R1 is a -C1-6 alkyl or has Formula 2:
Formula 2
wherein the or each group R2-R6 is independently selected from –H, -C1-6
20 alkyl,
-halogen, -OH and -O-C1-6 alkyl.
More suitably, the substituted flavonoid compound comprises one or more
substituent groups independently selected from -OH, -OR1 and -O-C(O)-R1; and
25 may optionally comprises one or more substituent groups selected from -C1-6
alkyl,
-C1-6 alkylene-OH, -C1-6 alkylene-O-R1, -CO2H and -CO2R1, and
wherein R1 is a -C1-6 alkyl or has Formula 2:
18
Formula 2
wherein the or each group R2-R6 is independently selected from –H, -C1-6
alkyl and -OH5 .
In some aspects, A is a dicarbonyl sequestering moiety that does not include a
benzoquinone moiety.
10 Suitably, 1X is selected from C1-6 alkylene and C2-6 alkenylene.
More suitably, 1X is a C1-6 alkylene.
The ability of a diacarbonyl sequestering moiety to form a stable compound with
15 a dicarbonyl molecule, such as methylglyoxal, could be tested by carrying out a
competition assay with a detection system [64] where the methylglyoxal produces
a fluorescent product that can be detected by HPLC.
LINKER MOIETY
20 The linker moiety –L- is divalent and may be any chemically non-active distancemaking
group (spacer) which joins the mitochondrial targeting moiety to the
dicarbonyl sequestering moiety, and enables the two moieties to remain bonded
together when crossing the plasma and mitochondrial membranes. In particular,
–L- is stable under physiological conditions and must be pharmaceutically
25 acceptable.
Suitably –L- is a linker moiety of Formula 5:
-(Z1)m-X1-Yn-[X2]s-(Z2)t-
30
Formula 5
wherein:
Z1 and Z2 are independently selected from O, NR12, NR12-C(O), C(O)NR12, O-C(O),
19
C(O)-O and S;
Y is selected from O, NR12, NR12-C(O), C(O)NR12, O-C(O), C(O)-O, S and arylene;
wherein R12 is selected from –H, -C1-C6 alkyl and -aryl;
X1 is selected from C1-Cp alkylene, C2-Cp alkenylene, C2-Cp alkynylene and C3-Cp
cycloalkylene5 ;
X2 is selected from C1-Cq alkylene, C2-Cq alkenylene, C2-Cq alkynylene and C3-Cq
cycloalkylene;
each of m, n, s and t is independently selected from 0 or 1;
wherein p + q = 30 and wherein X1 and X2 are optionally substituted with one or
10 more functional groups independently selected from the group consisting of
hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl,
hydroxyalkyl, alkoxyalkyl, alkylthio, alkylsulfinyl, alkylsulfonyl, carboxyalkyl,
cyano, oxy, amino, alkylamino, aminocarbonyl, alkoxycarbonyl, aryloxycarbonyl,
alkylaminocarbonyl, arylaminocarbonyl, aralkylaminocarbonyl,
15 alkylcarbonylamino, arylcarbonylamino, aralkylcarbonylamino, alkylcarbonyl,
heterocyclocarbonyl, aminosulfonyl, alkylaminosulfonyl, alkylsulfonyl, and
heterocyclosulfonyl, or the substituent groups of adjacent carbon atoms in the
linker group can be taken together with the carbon atoms to which they are
attached to form a carbocycle or a heterocycle.
20
Suitably, Z1 is adjacent to the dicarbonyl sequestering moiety and Z2 is adjacent to
the mitochondrial targeting moiety.
More suitably, X1 is substituted with one or more functional groups
25 independently selected from the group consisting of alkyl, aryl, alkoxycarbonyl,
aryloxycarbonyl, alkylaminocarbonyl, arylaminocarbonyl, alkylcarbonylamino
and arylcarbonylamino.
More suitably, X2 is substituted with one or more functional groups
30 independently selected from the group consisting of alkyl, aryl, alkoxycarbonyl,
aryloxycarbonyl, alkylaminocarbonyl, arylaminocarbonyl, alkylcarbonylamino
and arylcarbonylamino.
More suitably, the linker moiety is of Formula 5, wherein:
35 Z1 and Z2 are as described above;
X1 and X2 are as described above;
Y is selected from NR12-C(O), C(O)NR12 and O-C(O);
20
R12 is as described above;
p = 12;
q = 5;
m, n, s and t are as described above; and
X1 and X2 are optionally substituted with one or more functional group5 s
independently selected from the group consisting alkyl, aryl, alkoxycarbonyl,
aryloxycarbonyl, alkylaminocarbonyl, arylaminocarbonyl, alkylcarbonylamino
and arylcarbonylamino.
10 More suitably, X1 is selected from C1-Cp alkylene.
More suitably, X2 is selected from C1-Cp alkylene.
More suitably, m is 1.
15
More suitably, –L- is a linker moiety of Formula 6:
-(Z1)m-X1-(Z2)t-
20 Formula 6
wherein Z1, m, Z2 and t have the same meanings as defined above, X1 is selected
from C1-Cp alkylene, C2-Cp alkenylene, C2-Cp alkynylene and C3-Cp cycloalkylene
and Cp =30.
25
More suitably, –L- is a linker moiety of Formula 6 and Z1 and Z2 are
independently selected from O, NR12, NR12-C(=O) and C(=O)NR12.
More suitably, X1 is selected from C1-Cp alkylene.
30
More suitably, -L- is a linker moiety of Formula 6, wherein Cp =25; more
suitably, Cp = 20; more suitably, Cp = 15; more suitably, Cp = 12; more suitably,
Cp = 10; more suitably, Cp = 9; more suitably, Cp = 8; more suitably, Cp = 7;
more suitably, Cp = 6.
35
More suitably –L- is a linker moiety of Formula 7:
21
-(Z1)m-(C1-Cp) alkylene-
Formula 7
wherein Z1 and m have the same meanings as defined above and Cp =305 .
Suitably, Z1 is adjacent to the dicarbonyl sequestering moiety and the C1-Cp
alkylene is adjacent to the mitochondrial targeting moiety.
10 More suitably, –L- is a linker moiety of Formula 7 and m is 1 and Z1 is selected
from O and C(O)NR12.
More suitably, –L- is a linker moiety of Formula 7 and R12 is selected from –H
and -C1-C6 alkyl.
15
More suitably, –L- is a linker moiety of Formula 7 and m is 1 and Z1 is C(O)NH.
More suitably, –L- is a linker moiety of Formula 7 wherein Cp =25; more suitably,
Cp = 20; more suitably, Cp = 15; more suitably, Cp = 10; more suitably, Cp = 9;
20 more suitably, Cp = 8; more suitably, Cp = 7; more suitably, Cp = 6
More suitably, –L- is a linker moiety of Formula 7 and the C1-Cp alkylene is a C3-
C6 alkylene.
25 More suitably, –L- is a linker moiety of Formula 7, wherein m is 1, Z1 is selected
from O and C(O)NR12; and the C1-Cp alkylene is selected from a C3-C6 alkylene.
More suitably, –L- is a linker moiety of Formula 7, wherein m is 1, Z1 is C(O)NH;
and the C1-Cp alkylene is selected from a C3-C6 alkylene.
30
In one aspect, –L- is a linker moiety of Formula 8:
Formula 8
22
wherein R13 is a C1-C6 alkylene, and R14 is a C1-C6 alkylene.
In one aspect, –L- is a linker moiety of Formula 9:
5
Formula 9
10 wherein R13 is a C1-C6 alkylene, and R14 is a C1-C6 alkylene.
More suitably, for Formula 8 or 9 R13 is –CH2-CH2-CH2-.
More suitably, for Formula 8 or 9 R14 is–CH2-CH2-CH2-.
15
Linker moieties of Formula 8 or 9 are described in US 2009/0099080.
MITOCHONDRIAL TARGETING MOIETY
Many mitochondrial targeting moieties are known in the art. Compounds
20 comprising mitochondrial targeting moieties accumulate in high concentrations
within mitochondria following administration.
The accumulation of compounds comprising mitochondrial targeting moieties
within mitochondria may, for example, be driven by plasma membrane potential
25 and/or mitochondrial membrane potentials. Such accumulation can often be
adequately described by the Nernst equation and, for example, for compounds
comprising a triphenylphosphonium cation may be 10-fold per 60 mV membrane
potential under typical biological conditions [25-27]. As a result, compounds
comprising a mitochondrial targeting moiety, such as the triphenylphosphonium
30 cation, may accumulate several hundred-fold or more within mitochondria in
vivo assuming plasma and mitochondrial membrane potentials of 30 mV and 160
mV respectively [28, 29].
23
Suitably, the mitochondrial targeting moiety B is a cationic mitochondrial
targeting moiety or a mitochondrial targeting peptide.
A range of mitochondrial targeting peptides are known in the art. Suitable
examples are disclosed in US 2009/00990805 .
Suitably, the mitochondrial targeting moiety B is a cationic mitochondrial
targeting moiety. A cationic mitochondrial targeting moiety will also be
associated with a pharmaceutically acceptable anion.
10
Suitably, the anion is selected from acetate, hydrochloride/chloride,
hydrobromide/bromide, hydroiodide/iodide, bisulfate, sulfate, methylsulfonate,
nitrate, phosphate, hydrogen phosphate, dihydrogen phosphate and
trifluoroacetate salts.
15
Suitably, the mitochondrial targeting moiety B is a lipophilic cation.
Liphophilic cations are suitable mitochondrial targeting moieties because they
can readily pass directly through phospholipid bilayers without having to
20 overcome large energy barriers or requiring a specific uptake mechanism, and
they accumulate substantially within mitochondria due to the large membrane
potential.
Without wishing to be bound to one theory, it is believed that lipophilic cations
25 are taken up from a positively charged cellular compartment into a negatively
charged compartment until a sufficiently large concentration gradient is built up
to equalize the electrochemical potential of the molecules in the two
compartments. For every 60 mV increase in membrane potential, there will be
approximately tenfold accumulation of the lipophilic cation within mitochondria.
30 Because the plasma membrane has a negative 30-60 mV potential on the inside,
lipophilic cations will accumulate 5 to 10 fold in the cytosol. Lipophilic cations
within the cytosol will accumulate in mitochondria because the mitochondrial
membrane potential is typically about 140 to 180 mV.
35 Suitably, the mitochondrial targeting moiety B is selected from:
(i) cationic mitochondrial targeting moieties comprising a quaternary ammonium
or phosphonium cation;
24
(ii) cationic mitochondrial targeting moieties comprising a 1,4a,8-triaza-
2,3,4,5,6,7-hexahydro-1H-napthalene compound; and
(iii) cationic mitochondrial targeting moieties comprising a Rhodamine
compound.
5
More suitably B is (i) a cationic mitochondrial targeting moiety comprising a
quaternary ammonium or phosphonium cation of Formula 10:
Formula 10
10 wherein:
D is phosphorous, nitrogen or arsenic; and
each of R15, R16 and R17 is independently selected from substituted or
unsubstituted alkyl, benzyl, aryl and heteroaryl.
15 More suitably D is phosphorous.
More suitably, each of R15, R16 and R17 is independently selected from substituted
or unsubstituted alkyl, benzyl, phenyl, naphthyl, furanyl, pyridyl and thiophenyl.
20 More suitably, where any of R15, R16 and R17 are substituted, the substituted alkyl,
benzyl, aryl or heteroaryl are substitued with from 1 to 3 substitutents selected
from the group consisting of –halogen, -OH, -SH, -OC1-6 alkyl, -SC1-6 alkyl, -SPh, -
C1-6 alkyl,
-C2-6 alkenyl, -C1-6 alkynyl, -C1-6 hydroxyalkyl, -C1-6 aminoalkyl, -C6-18 araalkyl, -C6-
25 12 aryl, -C3-8 cylcoalkyl, -C1-12 heteroaryl and -C1-12 heterocyclyl.
Suitably, where one or more of R15, R16 and R17 is independently selected from
substituted or unsubstituted alkyl, each alkyl group is independently selected
from a substituted or unsubstituted C1-30 alkyl. More suitably, each alkyl group is
30 independently selected from a substituted or unsubstituted C1-25 alkyl; from a
substituted or unsubstituted C1-20 alkyl; from a substituted or unsubstituted C1-15
alkyl; from a substituted or unsubstituted C1-10 alkyl.
More suitably each of R15, R16 and R17 are the same.
35
25
More suitably each R15, R16 and R17 is an unsubstituted or a substituted aryl group.
More suitably each R15, R16 and R17 is an unsubstituted aryl group.
More suitably each aryl group is phenyl.
5
Most suitably, B is a triphenylphosphonium (TPP) cation, which has the Formula
11:
10 Formula 11
The large hydrophobic radius of the TPP cation enables it to pass easily through
the phospholipid bilayer relative to other cations.
15 Lipophilic triphenylphosphonium (TPP) cation functionality is suitable to target
mitochondria and it has been shown to direct a wide variety of antioxidants,
probes and bioactive molecules to mitochondria in cells, animal models and
patients following intravenous, oral or intraperitoneal administration [25-27].
Uptake occurs directly through the phospholipid bilayer and does not require a
20 protein carrier, while the extent of accumulation into mitochondria is determined
by the membrane potential.
More suitably, B is (ii) a cationic mitochondrial targeting moiety comprising
1,4a,8-triaza-2,3,4,5,6,7-hexahydro-1H-napthalene compound of Formula 12
25 ;
Formula 12
26
wherein R18 is -H, -C1-C6 alkyl, -C1-C6 alkenyl, -C1-C6 alkynyl, -C1-C6alkylenehalogen,
-aryl, -aryl-C1-C6alkyl or R19R20R21Si wherein R19, R20 and R21 are independently
selected from -C1-C6 alkyl and -aryl; and v is 1, 2 or 3. Such cationi5 c
mitochondrial targeting moieties are described in US 2009/099080.
As disclosed in US 2009/099080, linker moieties of Formula 9 are suitable for
use with cationic mitochondrial targeting moieties of Formula 12
10
More suitably, B is (iii) a cationic mitochondrial targeting moiety comprising a
Rhodamine compound of Formula 13:
15 Formula 13
wherein R22, R23 and R24 are independently selected from -H and -C1-C6 alkyl;
R26 and R27 are independently selected from –H or –CH3;
R28 is selected from –CO2R29 , -O-C(O)-R29, -C(O)-NHR29 and –NH-C(O)-R29; and
20 one of R25 and R29 is a bond to the linker L and the other of R25 and R28 is selected
from -H and -C1-C6 alkyl.
A large number of Rhodamine derivatives such as Rhodamine 123, Rhodamine B,
Rhodamine 6G, Rhodamine 19, Rhodamine 110, and Rhodamine 116 are
25 commercially available from suppliers such as Acos Organics, Aldrich and Fluka.
The synthesis of Rhodamine derivatives has also been reviewed [54].
FURTHER COMPOUNDS OF FORMULA 1
Suitably, the compound or pharmaceutically acceptable salt of Formula 1 is a salt
30 of Formula 14:
27
Formula 14
wherein R7, R8, R9, R10, R11, R15, R16, R17, Z1, X1, Y, X2, Z2, D, m, n, s and t have the
same meanings as described above. The salt of Formula 14 may optionall5 y
further comprise a pharmaceutically acceptable anion.
More suitably, the compound or pharmaceutically acceptable salt of Formula 1 is a
salt of Formula 15:
10
Formula 15
wherein R7, R8, R9, R10, R11, R15, R16, R17, Z1, X1, Z2, m and t have the same
meanings as described above. The salt of Formula 15 may optionally further
15 comprise a pharmaceutically acceptable anion.
More suitably, the compound of Formula 1 is MitoG which has the structure
shown in Formula 16:
28
Formula 16
wherein An- represents an optional pharmaceutically acceptable anion.
5
Another example of a compound of Formula 1 is MitoGamide, (3—(3,4-
diaminobenoylamino)propyl)triphenylphosphonium salt, which has the structure
shown in Formula 17:
10 Formula 17
wherein An- represents an optional pharmaceutically acceptable anion.
Suitably, the anion An- is selected from acetate, hydrochloride/chloride,
15 hydrobromide/ bromide, hydroiodide/iodide, bisulfate, sulfate, methylsulfonate,
nitrate, phosphate, hydrogen phosphate, dihydrogen phosphate and
trifluoroacetate salts.
More suitably, the anion An- is the chloride salt.
20
29
These molecules comprise a mitochondrial targeting group, such as a
triphenylphosphonium ion (TPP), linked through an oxygen atom to a
sequestering group, such as an o-phenylenediamine, that reacts selectively with
methylglyoxal and glyoxal. Alkoxy-substituted phenylenediamines have been
used for detecting 1,2-dicarbonyls because of the enhanced reactivity due to th5 e
electron donating alkoxy substituent [28, 29]. These have been as used
derivatizing agents for the detection of dicarbonyls, reacting to form stable
quinoxaline products [12, 13, 28].
10 Compounds such as MitoG are demonstrated to be protective, as shown in the
examples section.
Compounds such as MitoGamide are also protective and show increased stability.
15 In designing the MitoG compounds such as MitoGamides, the characteristics
required to bring about the therapeutic benefits of the invention were considered.
A need to pull electrons into a separate part of the molecular structure was
identified. The inventors identified molecular groups which could be substituted
in order to tune the reactivity of the diamine group. Solutions to this problem are
20 provided by the compounds of Formula 1. Preferred solutions include the
MitoGamide molecule which provides benefits including enhanced stability.
Compounds of Formula 1, which include compounds specifically named above,
may form pharmaceutically acceptable salts. These salts include acid addition
25 salts (including di-acids) and base salts. Pharmaceutically acceptable acid
addition salts include nontoxic salts derived from inorganic acids such as
hydrochloric acid, nitric acid, phosphoric acid, sulfuric acid, hydrobromic acid,
hydroiodic acid, hydrofluoric acid, and phosphorous acids, as well nontoxic salts
derived from organic acids, such as aliphatic mono- and dicarboxylic acids,
30 phenyl-substituted alkanoic acids, hydroxy alkanoic acids, alkanedioic acids,
aromatic acids, aliphatic and aromatic sulfonic acids, etc. Such salts include
acetate, adipate, aspartate, benzoate, besylate, bicarbonate, carbonate, bisulfate,
sulfate, borate, camsylate, citrate, cyclamate, edisylate, esylate, formate,
fumarate, gluceptate, gluconate, glucuronate, hexafluorophosphate, hibenzate,
35 hydrochloride/chloride, hydrobromide/bromide, hydroiodide/iodide,
isethionate, lactate, malate, maleate, malonate, mesylate, methylsulfonate,
naphthylate, 2-napsylate, nicotinate, nitrate, orotate, oxalate, palmitate, pamoate,
30
phosphate, hydrogen phosphate, dihydrogen phosphate, pyroglutamate,
saccharate, stearate, succinate, tannate, tartrate, tosylate, trifluoroacetate and
xinofoate salts.
Pharmaceutically acceptable base salts include nontoxic salts derived from bases5 ,
including metal cations, such as an alkali or alkaline earth metal cation, as well as
amines. Examples of suitable metal cations include sodium (Na+) potassium (K+),
magnesium (Mg2+), calcium (Ca2+), zinc (Zn2+), and aluminum (Al3+). Examples
of suitable amines include arginine, N,N'-dibenzylethylenediamine,
10 chloroprocaine, choline, diethylamine, diethanolamine, dicyclohexylamine,
ethylenediamine, glycine, lysine, N-methylglucamine, olamine, 2-amino-2-
hydroxymethyl-propane-1,3-diol, and procaine. For a discussion of useful acid
addition and base salts, see S. M. Berge et al., J. Pharm. Sci. (1977) 66:1-19; see
also Stahl and Wermuth, Handbook of Pharmaceutical Salts: Properties,
15 Selection, and Use (2002).
Pharmaceutically acceptable salts may be prepared using various methods. For
example, one may react a compound of Formula 1 with an appropriate acid or
base to give the desired salt. One may also react a precursor of the compound of
20 Formula 1 with an acid or base to remove an acid- or base-labile protecting group
or to open a lactone or lactam group of the precursor. Additionally, one may
convert a salt of the compound of Formula 1 to another salt through treatment
with an appropriate acid or base or through contact with an ion exchange resin.
Following reaction, one may then isolate the salt by filtration if it precipitates
25 from solution, or by evaporation to recover the salt. The degree of ionization of
the salt may vary from completely ionized to almost non-ionized.
Compounds of Formula 1 may also exist in unsolvated and solvated forms. The
term “solvate” describes a molecular complex comprising the compound and one
30 or more pharmaceutically acceptable solvent molecules (e.g., EtOH). The term
“hydrate” is a solvate in which the solvent is water. Pharmaceutically acceptable
solvates include those in which the solvent may be isotopically substituted (e.g.,
D2O, acetone-d6, DMSO-d6).
35 A currently accepted classification system for solvates and hydrates of organic
compounds is one that distinguishes between isolated site, channel, and metalion
coordinated solvates and hydrates. See, e.g., K. R. Morris (H. G. Brittain ed.)
31
Polymorphism in Pharmaceutical Solids (1995). Isolated site solvates and
hydrates are ones in which the solvent (e.g., water) molecules are isolated from
direct contact with each other by intervening molecules of the organic compound.
In channel solvates, the solvent molecules lie in lattice channels where they are
next to other solvent molecules. In metal-ion coordinated solvates, the solven5 t
molecules are bonded to the metal ion.
When the solvent or water is tightly bound, the complex will have a well-defined
stoichiometry independent of humidity. When, however, the solvent or water is
10 weakly bound, as in channel solvates and in hygroscopic compounds, the water or
solvent content will depend on humidity and drying conditions. In such cases,
non-stoichiometry will typically be observed.
Compounds of Formula 1 may also exist as multi-component complexes (other
15 than salts and solvates) in which the compound (drug) and at least one other
component are present in stoichiometric or non-stoichiometric amounts.
Complexes of this type include clathrates (drug-host inclusion complexes) and cocrystals.
The latter are typically defined as crystalline complexes of neutral
molecular constituents which are bound together through non-covalent
20 interactions, but could also be a complex of a neutral molecule with a salt. Cocrystals
may be prepared by melt crystallization, by recrystallization from
solvents, or by physically grinding the components together. See, e.g., O.
Almarsson and M. J. Zaworotko, Chem. Commun. (2004) 17:1889-1896. For a
general review of multi-component complexes, see J. K. Haleblian, J. Pharm. Sci.
25 (1975) 64(8):1269-88.
SYNTHETIC METHODS
Methods for the chemical synthesis of compounds of the present invention are
described herein. These methods may be modified and/or adapted in known
30 ways in order to facilitate the synthesis of additional compounds within the scope
of the present invention. The amounts of reactants given are for guidance.
Descriptions of general laboratory methods and procedures, useful for the
preparation of the compounds of the present invention, are described in Vogel's
Textbook of Practical Organic Chemistry (5th edition, Ed. Furniss, B. S.,
35 Hannaford, A. J., Smith, P. W. G., Tatchell, A. R., Longmann, UK).
The synthesis of compounds of the present invention may have three key steps:
32
(i) formation of the dicarbonyl sequestering moiety;
(ii) attachment of the linking group to the dicarbonyl sequestering moiety; and
(iii) attachment of the linking group to the mitochondrial targeting moiety.
In some cases, the starting material for formation of the dicarbonyl sequesterin5 g
moiety may already include part or all of the linking group. Where all of the
linking group is included, then step (ii) is omitted.
These three steps can be carried out in any order, which will be dependent on the
10 methods used and the nature of each of the three groups. It is possible that the
formation of the dicarbonyl sequestering moiety can be interrupted by linking a
precursor to the linking group. If necessary, protecting groups can be employed
to avoid any unwanted reactions occurring during the synthesis.
15 Formation of the dicarbonyl sequestering moiety: this will depend on the nature
of the dicarbonyl sequestering moiety, and can usually be based on the disclosed
routes for forming that moiety. It is sometimes convenient to synthesise the
dicarbonyl sequestering moiety with a heteroatom (O, S or NH) already attached
to the dicarbonyl sequestering moiety in the position where this moiety is desired
20 to be attached to the linker moiety. Such a heteroatom can aid the joining of the
linking group to the dicarbonyl sequestering moiety. The dicarbonyl sequestering
moiety may also be synthesised with a functional group present, such as a
carboxylic acid, which is suitable for further functionalization.
25 Linking the linking group to the mitochondrial targeting moiety: it is generally
preferred to carry this step out by heating an halogenated precursor, preferably
an iodinated or brominated precursor (RBr or RI), or a precursor with a strong
leaving group, such as a mesylate, sometimes in an appropriate solvent with 2-3
equivalents of the mitochondrial targeting moiety precursor under argon for up to
30 several days. R can either be the linking group, the linking group already
attached to the dicarbonyl sequestering moiety, or the linking group attached to a
precursor of the dicarbonyl sequestering moiety. Where an halogenated
precursor is used in the reaction, the product compound is then isolated as its
bromide or iodide salt. To do this the solvent is removed (if necessary), the
35 product is then triturated repeatedly with a compound such as diethyl ether, until
an solid remains. This can then dissolved in a solvent, e.g. dichloromethane, and
precipitated with diethyl ether to remove the excess unreacted material. This can
33
be repeated. Purification can involve recrystallisation, for example, from
methylene chloride/diethyl ether or chromatography on silica gel eluting with
dichloromethane/ethanol mixtures.
Linking the linking group to the dicarbonyl sequestering moiety: this will depen5 d
on the nature of the dicarbonyl sequestering moiety. One method of achieving
this linking is to synthesise the linking group as part of the dicarbonyl
sequestering moiety. In this case, the linking group would suitably have a
functional group at the end of the linking group that is to be attached to the
10 mitochondrial targeting moiety. Such a functional group may, for example, be a
good leaving group such as a mesylate group which could then be reacted with the
precursor of the mitochondrial targeting moiety. Alternatively, if the dicarbonyl
sequestering moiety has been synthesised with a suitable functional group in
place (see above), it may be reacted with a combined mitochondrial targeting15
linker precursor moiety using a coupling agent or following activation of one
partner as a sulfonyl halide or acid halide. The combined mitochondrial
targeting-linker precursor moiety would have an appropriate functional group on
the linker, such as an amine. Thus, a carbodiimide or other coupling agent may
be used to form an amide from these moieties. For example, in the synthesis of
20 MitoGamide, the dicarbonyl sequestering group armed with a carboxylic acid can
be reacted with a TPP-linker-amine using a coupling agent to form an amide. In
theory, a dicarbonyl seqestering group-amine could be reacted with TPP-linkercarboxylic
acid using a coupling agent provided that the reacting amine is more
nucleophilic than the dicarbonyl sequestering unit, or the latter is protected.
25 Similarly, sulfonyl chlorides react rapidly with amines to form sulfonamides in
the presence of relatively weak bases to remove HCl, again the sequestering group
may need protection to avoid reacting with the sulfonyl chloride.
The compounds of Formula 1 may be prepared using the techniques described
30 below. Some of the schemes and examples may omit details of common
reactions, including oxidations, reductions, and so on, separation techniques
(extraction, evaporation, precipitation, chromatography, filtration, trituration,
crystallization, and the like), and analytical procedures, which are known to
persons of ordinary skill in the art of organic chemistry. The details of such
35 reactions and techniques can be found in a number of treatises, including Richard
Larock, Comprehensive Organic Transformations, A Guide to Functional Group
Preparations, 2nd Ed (2010), and the multi-volume series edited by Michael B.
34
Smith and others, Compendium of Organic Synthetic Methods (1974 et seq.).
Starting materials and reagents may be obtained from commercial sources or
may be prepared using literature methods. Some of the reaction schemes may
omit minor products resulting from chemical transformations (e.g., an alcohol
from the hydrolysis of an ester, CO2 from the decarboxylation of a diacid, etc.). I5 n
addition, in some instances, reaction intermediates may be used in subsequent
steps without isolation or purification (i.e., in situ).
In some of the reaction schemes and examples below, certain compounds can be
10 prepared using protecting groups, which prevent undesirable chemical reaction at
otherwise reactive sites. Protecting groups may also be used to enhance solubility
or otherwise modify physical properties of a compound. For a discussion of
protecting group strategies, a description of materials and methods for installing
and removing protecting groups, and a compilation of useful protecting groups
15 for common functional groups, including amines, carboxylic acids, alcohols,
ketones, aldehydes, and so on, see T. W. Greene and P. G. Wuts, Protecting
Groups in Organic Chemistry, 4th Edition, (2006) and P. Kocienski, Protective
Groups, 3rd Edition (2005).
20 Generally, the chemical transformations described throughout the specification
may be carried out using substantially stoichiometric amounts of reactants,
though certain reactions may benefit from using an excess of one or more of the
reactants. Additionally, many of the reactions disclosed throughout the
specification may be carried out at about room temperature (RT) and ambient
25 pressure, but depending on reaction kinetics, yields, and so on, some reactions
may be run at elevated pressures or employ higher temperatures (e.g., reflux
conditions) or lower temperatures (e.g., -78°C. to 0°C.). Any reference in the
disclosure to a stoichiometric range, a temperature range, a pH range, etc.,
whether or not expressly using the word "range," also includes the indicated
30 endpoints.
Many of the chemical transformations may also employ one or more compatible
solvents, which may influence the reaction rate and yield. Depending on the
nature of the reactants, the one or more solvents may be polar protic solvents
35 (including water), polar aprotic solvents, non-polar solvents, or some
combination. Representative solvents include saturated aliphatic hydrocarbons
(e.g., n-pentane, n-hexane, n-heptane, n-octane); aromatic hydrocarbons (e.g.,
35
benzene, toluene, xylenes); halogenated hydrocarbons (e.g., methylene chloride,
chloroform, carbon tetrachloride); aliphatic alcohols (e.g., methanol, ethanol,
propan-1-ol, propan-2-ol, butan-1-ol, 2-methyl-propan-1-ol, butan-2-ol, 2-
methyl-propan-2-ol, pentan-1-ol, 3-methyl-butan-1-ol, hexan-1-ol, 2-methoxyethanol,
2-ethoxy-ethanol, 2-butoxy-ethanol, 2-(2-methoxy-ethoxy)-ethanol, 5 2-
(2-ethoxy-ethoxy)-ethanol, 2-(2-butoxy-ethoxy)-ethanol); ethers (e.g., diethyl
ether, di-isopropyl ether, dibutyl ether, 1,2-dimethoxy-ethane, 1,2-diethoxyethane,
1-methoxy-2-(2-methoxy-ethoxy)-ethane, 1-ethoxy-2-(2-ethoxy-ethoxy)-
ethane, tetrahydrofuran, 1,4-dioxane); ketones (e.g., acetone, methyl ethyl
10 ketone); esters (methyl acetate, ethyl acetate); nitrogen-containing solvents (e.g.,
formamide, N,N-dimethylformamide, acetonitrile, N-methyl-pyrrolidone,
pyridine, quinoline, nitrobenzene); sulfur-containing solvents (e.g., carbon
disulfide, dimethyl sulfoxide, tetrahydro-thiophene-1,1,-dioxide); and
phosphorus-containing solvents (e.g., hexamethylphosphoric triamide).
15
APPLICATIONS
A key aspect of the invention is the blocking or amelioration of damage caused by
hyperglycaemia. The invention finds application in the treatment or prevention
of downstream consequences of hyperglycaemia.
20
One application for a compound of formula 1, as defined above, or a
pharmaceutically acceptable salt thereof, is for use in the prevention or treatment
of hyperglycaemia.
25 Hyperglycaemia can occur as an age related syndrome. Hyperglycaemia can
occur in sepsis, and/or in intensive care/emergency room admissions.
Hyperglycaemia can occur as a complication of pregnancy.
Thus, prevention of hyperglycaemia can be important for subjects with a health
30 state that increases the risk of hyperglycaemia compared to a normal healthy
subject who does not have that health state. Suitably, there may be provided a
compound of formula 1, as defined above, or a pharmaceutically acceptable salt
thereof, for use in the prevention or treatment of hyperglycaemia in a subject with
a health state selected from sepsis, pregnancy or a health state requiring critical
35 care.
36
Most specifically, the invention is applied in diabetes such as hyperglycaemic
diabetes. The invention finds application in the treatment or prevention of the
downstream consequences of hyperglycaemia and diabetes (such as
hyperglycaemic diabetes), for example, to prevent or reduce damage to any
suitable organs and tissues such as eyes, heart, kidneys, nervous system and/5 or
pancreas.
The invention is applied to the treatment or prevention of mitochondrial damage
associated with dysfunction or dysregulation of glycaemic control, for example
10 mitochondrial damage associated with hyperglycaemia.
Most suitably the invention is applied to the treatment or prevention of molecular
consequences of hyperglycaemia.
15 In one aspect, the invention relates to a compound of Formula 1 or a
pharmaceutical salt thereof, for use in slowing the deleterious effects of aging in a
subject.
In another aspect, the invention relates to a compound of Formula 1 or a
20 pharmaceutical salt thereof, for use in preventing or reducing glycation-induced
toxicity.
In another aspect, the invention relates the invention relates to a compound of
Formula 1 or a pharmaceutical salt thereof, for use in preventing or reducing
25 respiratory depression, in particular dicarbonyl-induced respiratory depression.
In another aspect, the invention relates the invention relates to a compound of
Formula 1 or a pharmaceutical salt thereof, for use to protect against cell death, in
particular to protect against glycation-induced cell death.
30
A further aspect of the invention provides a compound of formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use in the preservation of
organ and tissue for surgical transplants. In such an application the compound of
formula 1 or a pharmaceutically acceptable salt thereof may suitably be
35 administered as a component of a tissue preservation fluid. In this aspect, any
suitable organ and tissue for surgical transplants may be preserved; illustrative
37
organ transplants include eyes (e.g. cornea), heart, kidney, nerve cells and
pancreas.
A further aspect of the invention provides a compound of formula 1, as defined
above, or a pharmaceutically acceptable salt thereof, for use in the storage of blood5 .
In such an application the compound of formula 1 or a pharmaceutically acceptable
salt thereof may suitably be administered as a component of a preservation fluid.
Suitably the invention is applied to mammals, most suitably humans.
10
The invention may be applied to retinal degeneration. Retinal degeneration is a
correlate of diabetic complications. The invention may be usefully applied to any
other complication of diabetes, specifically hyperglycaemic diabetes.
15 ADMINISTRATION
The compound of the invention can be administered in solid or liquid form such
as tablets, powders, capsules, pellets, solutions, suspensions elixirs, emulsions,
gels, creams, or suppositories, including rectal and urethral suppositories.
20 Suitably compounds of the invention may be used to treat humans.
Suitably the dose for humans is orally administered.
Suitably the dose for humans is one per day.
25
Suitably the dose for humans is provided in tablet form.
The compounds or compositions of the invention may be administered by
parenteral administration.
30
The compound of the invention may be administered intravenously.
The compound of the invention can be administered in a dose of approximately
20-40mgs per day. Suitably the dose for humans is approximately 80mgs per
35 day.
38
Dosing information is provided for an average adult human unless otherwise
stated. It is well within the skill of a physician to vary the dose according to
characteristics of the patient being treated, for example age, weight, gender etc.
The compound of the invention may be administered intraocularly5 .
The compound of the invention may be administered intravenously.
The compound of the invention may be administered intraperitoneally.
10
The compound of the invention may be administered as eye drops.
Administration may be to any suitable tissue or organ, for example, the
compounds or compositions of the invention may be administered to the eye,
15 heart, kidney, nervous system and/or pancreas.
The compound of the invention may be administered in combination with one or
more pharmaceutically acceptable excipients, carriers or diluents.
20 Suitable excipients, carriers and diluents can be found in standard
pharmaceutical texts. See, for example, Handbook for Pharmaceutical Additives,
3rd Edition (eds. M. Ash and I. Ash), 2007 (Synapse Information Resources, Inc.,
Endicott, New York, USA) and Remington: The Science and Practice of
Pharmacy, 21st Edition (ed. D. B. Troy) 2006 (Lippincott, Williams and Wilkins,
25 Philadelphia, USA) which are incorporated herein by reference.
Excipients for use in the compositions of the invention include, but are not
limited to microcrystalline cellulose, sodium citrate, calcium carbonate, dicalcium
phosphate and glycine may be employed along with various disintegrants such as
30 starch (and preferably corn, potato or tapioca starch), alginic acid and certain
complex silicates, together with granulation binders like polyvinylpyrrolidone,
sucrose, gelatin and acacia. Additionally, lubricating agents such as magnesium
stearate, sodium lauryl sulfate and talc are often very useful for tabletting
purposes. Solid compositions of a similar type may also be employed as fillers in
35 gelatin capsules; preferred materials in this connection also include lactose or
milk sugar as well as high molecular weight polyethylene glycols. When aqueous
suspensions and/or elixirs are desired for oral administration, the active
39
ingredient may be combined with various sweetening or flavouring agents,
colouring matter or dyes, and, if so desired, emulsifying and/or suspending
agents as well, together with such diluents as water, ethanol, propylene glycol,
glycerin and various like combinations thereof.
5
Pharmaceutical carriers include solid diluents or fillers, sterile aqueous media
and various non-toxic organic solvents, and the like.
Pharmaceutically acceptable carriers include gums, starches, sugars, cellulosic
10 materials, and mixtures thereof. The compound can be administered to a subject
by, for example, subcutaneous implantation of a pellet. The preparation can also
be administered by intravenous, intra-arterial, or intramuscular injection of a
liquid preparation oral administration of a liquid or solid preparation, or by
topical application. Administration can also be accomplished by use of a rectal
15 suppository or a urethral suppository.
Further, as used herein “pharmaceutically acceptable carriers” are well known to
those skilled in the art and include, but are not limited to, 0.01-0.1M and
preferably 0.05M phosphate buffer or 0.9% saline. Additionally, such
20 pharmaceutically acceptable carriers may be aqueous or non-aqueous solutions,
suspensions, and emulsions. Examples of non-aqueous solvents are propylene
glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic
esters such as ethyl oleate. Aqueous carriers include water, alcoholic/aqueous
solutions, emulsions or suspensions, including saline and buffered media.
25
Pharmaceutically acceptable parenteral vehicles include sodium chloride
solution, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's and
fixed oils. Intravenous vehicles include fluid and nutrient replenishers, electrolyte
replenishers such as those based on Ringer's dextrose, and the like. Preservatives
30 and other additives may also be present, such as, for example, antimicrobials,
antioxidants, collating agents, inert gases and the like.
Pharmaceutically acceptable carriers for controlled or sustained release
compositions administerable according to the invention include formulation in
35 lipophilic depots (e.g. fatty acids, waxes, oils). Also comprehended by the
invention are particulate compositions coated with polymers (e.g. poloxamers or
poloxamines) and the compound coupled to antibodies directed against tissue40
specific receptors, ligands or antigens or coupled to ligands of tissue-specific
receptors.
Pharmaceutically acceptable carriers include compounds modified by the
covalent attachment of water-soluble polymers such as polyethylene glycol5 ,
copolymers of polyethylene glycol and polypropylene glycol, carboxymethyl
cellulose, dextran, polyvinyl alcohol, polyvinylpyrrolidone or polyproline are
known to exhibit substantially longer half-lives in blood following intravenous
injection than do the corresponding unmodified compounds (Abuchowski and
10 Davis, Soluble Polymer-Enzyme Adducts, Enzymes as Drugs, Hocenberg and
Roberts, eds., Wiley-Interscience, New York, N.Y., (1981), pp 367-383; and [65]).
Such modifications may also increase the compound's solubility in aqueous
solution, eliminate aggregation, enhance the physical and chemical stability of the
compound, and greatly reduce the immunogenicity and reactivity of the
15 compound. As a result, the desired in vivo biological activity may be achieved by
the administration of such polymer-compound abducts less frequently or in lower
doses than with the unmodified compound.
MASS SPECTROMETRY
20 The invention also finds application as a mass spectrometry probe for detection of
reactive dicarbonyls.
These mass spectrometry methods enable the assessment of the importance of
mitochondrial damage caused by methylglyoxal and glyoxal. Hence, the
25 compounds of Formula 1, for example, the mitochondria-selective molecule
MitoG, may be used to assess relative changes in the levels of these damaging
species within mitochondria in cells and in vivo.
The mode of action of MitoG, is shown in Fig. 1B. The ability to quantify the
30 accumulation of the quinoxaline products from the in situ reaction of MitoG with
methylglyoxal and glyoxal provides an opportunity to assess changes in the levels
of these compounds in mitochondria in cells and in vivo. This can be done by an
extension of an approach recently developed to assess levels of mitochondrial
hydrogen peroxide in vivo by the use of a mitochondria-targeted peroxide
35 reactive compound, MitoB [30, 31]. In this methodology, a diagnostic exomarker
product, MitoP, was formed from MitoB, and its levels were determined ex vivo
by liquid chromatography-tandem mass spectrometry (LC-MS/MS) of tissue
41
homogenates relative to deuterated internal standards [30, 31]. The sensitivity of
such an approach is greatly enhanced by the inherent positive charge of the TPP
moiety that decreases the threshold for detection by mass spectrometry (MS),
enabling the analysis of femtomol compound/g wet weight tissue [30, 31]. Thus
relative changes in methylglyoxal and glyoxal levels within mitochondria can b5 e
assessed based upon the extent of accumulation of the MitoG-dicarbonyl
quinoxaline reaction products (Fig. 1B). Hence, compounds such as MitoG,
provide a mitochondria-targeted probe for methylglyoxal and glyoxal that can be
used for the evaluation of 1,2-dicarbonyl production within mitochondria in cells
10 and in vivo. These findings are consistent with mitochondrial glycation
contributing to the underlying pathology of hyperglycaemia in diabetes and
related disorders.
Further particular and preferred aspects are set out in the accompanying
15 independent and dependent claims. Features of the dependent claims may be
combined with features of the independent claims as appropriate, and in
combinations other than those explicitly set out in the claims.
Where an apparatus feature is described as being operable to provide a function,
20 it will be appreciated that this includes an apparatus feature which provides that
function or which is adapted or configured to provide that function.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described further, with
25 reference to the accompanying drawings, in which:
Fig. 1. shows the rationale and mechanism for the detection of intramitochondrial
dicarbonyls. (A) MitoG, a mitochondria-targeted glyoxal and
methylglyoxal trap, consists of a mitochondria-targeting TPP moiety and a
30 phenylenediamine group that reacts with 1,2-dicarbonyls. The TPP moiety of
MitoG leads to its uptake into tissues where it accumulates within mitochondria,
driven by both the plasma and mitochondrial membrane potentials. (B) Within
mitochondria MitoG can then react with glyoxal or methylglyoxal to form the
quinoxaline products, quinoxaline ether (QE) and methylquinoxaline ether
35 (MQE) (present as two isomers, MQE1 and MQE2). These products can then be
quantified by LC-MS/MS relative to deuterated internal standards (ISs) to
42
provide a measure of the amount of free glyoxal and methylglyoxal present within
mitochondria in cells and in vivo.
Fig. 2. shows the syntheses of MitoG, MQE and QE.
5
Fig. 3. shows the in vitro characterization of MitoG, MQE and QE. (A) Ultra
Violet/ Visible (UV/V)is scanning spectra of 100 μM MitoG shows the
characteristic of its component TPP and 4-hexyloxyphenylene-1,2-diamine (HP)
moieties. (B) UV/Vis scanning spectra of 100 μM MitoG, MQE and QE. (C)
10 Fluorescent excitation spectra (emission 433 nm) and emission spectra
(excitation 344 nm) of 10 μM MitoG, MQE and QE. MitoG was not fluorescent.
MQE and QE had peak excitation and emission wavelengths of 344 nm and 433
nm, respectively. (D) Reverse Phase-High Performance Liquid Chromatography
(RP-HPLC) profile of 10 nmol each of MitoG, MQE and QE. Absorbance (red) at
15 220 nm, fluorescence (blue) was observed at excitation and emission wavelengths
of 344 nm and 433 nm, respectively. (E) UV/Vis scanning spectra of 100 μM
MitoG and 1 mM methylglyoxal or glyoxal in KCl buffer after incubation at 37oC
for 2 h. (F) Fluorescent excitation and emission spectra of 10 μM MitoG and 20
μM methylglyoxal, or of 20 μM MitoG and 40 μM glyoxal, in KCl buffer after
20 incubation at 37°C for 2 h. (G) MitoG (5 mM) and 10 mM methylglyoxal were
incubated in 10 μl KCl buffer at 37°C for 2 h, then 1 μl mixture was assessed by
RP-HPLC. (H) The identity of the product peak was confirmed by spiking the
reaction mixture with 10 nmol MQE standard. Experiments with glyoxal gave
similar results (data not shown).
25
Fig. 4. shows the in vitro reaction of MitoG with methylglyoxal and glyoxal. (A)
The reactions between MitoG (100 μM) and 1,2-dicarbonyls (25 μM) at 37°C were
followed from the formation of the quinoxaline products at 345 nm. (B)
Fluorimetric detection of the reaction between MitoG and methylglyoxal (40 μM
30 each), and between MitoG and glyoxal (200 μM each) was observed by
monitoring the quinoxaline products at excitation and emission wavelengths of
344 and 433 nm, respectively. The changes in fluorescence caused by MQE and
QE formation was quantified from calibration curves constructed by plotting
fluorescence (excitation and emission wavelengths of 344 and 433 nm,
35 respectively) against known amounts of either quinoxaline and were linear up to
at least 20 WM.
Fig. 5. shows the uptake of MitoG by isolated mitochondria A TPP-selective
electrode was placed in a stirred chamber at 37°C containing 1 ml KCl buffer
43
supplemented with 4 μg/ml rotenone. Following calibration with five additions of
1 WM MitoG (arrowheads) RLM (1 mg protein/ml) were added, followed by 10
mM succinate and 500 nM FCCP (carbonylcyanide ptrifluoromethoxyphenylhydrazone)
where indicated. This trace is representative
of three independent experiments5 .
Fig. 6. shows the effects of MitoG on mitochondrial and cell function. (A, B)
RLM respiring on glutamate/malate at 37°C were incubated with various
concentrations of MitoG for 7 min in an oxygen electrode to measure coupled
10 respiration (A) before ADP was added to measure phosphorylating respiration
(B). Data are the percentage of the respiration rates of untreated controls (dashed
lines). (C and D) C2C12 cells (C) or BAECs [Bovine Aortic Endothelial Cells; Cell
Applications Inc, San Diego, CA] (D) were incubated with MitoG for 24 h and cell
survival was then determined using the MTS assay. Data are expressed as a
15 percentage of the untreated controls (dashed line). (E-H) BAECs were incubated
with MitoG for 2 h at 37°C and the cellular oxygen consumption rate (OCR) after
the sequential additions of oligomycin, FCCP and antimycin A/rotenone were
then measured using a Seahorse XF24 analyser. (E) OCR due to ATP synthesis,
(F) OCR due to proton leak, (G) reserve capacity and (H) non-mitochondrial
20 oxygen consumption. Results are means ± S.E. of three independent experiments.
*, P<0.05 or **, P<0.01 relative to untreated controls.
Fig. 7. shows the fragmentation of MQE and QE by tandem mass spectrometry.
Compounds (1 μM in 20% acetonitrile) were infused, at 2 μl/min, into a triple
25 quadrupole mass spectrometer. The indicated parent ions of MQE and QE and
their corresponding d15-variants were fragmented to generate the indicated
daughter ions.
Fig. 8. shows the LC-MS/MS analysis of MQE and QE. (A) QE and both isoforms
30 of MQE have parent ions with distinctive m/z ratios that fragment to form
characteristic daughter ions. (B) Standard curves based on the analyses of MQE
and QE by LC-MS/MS analysis relative to the corresponding deuterated ISs.
Fig. 9. shows the quantification of MQE and QE in cells. (A) and (B) BAECs were
35 incubated with 2 μM MitoG for 1 h and sometimes supplemented with 10 mM AG
or 2 μM FCCP. Methylglyoxal (A) or glyoxal (B) were then added, and after a
further 3 h incubation the levels of MQE and QE in the cell layers were
determined by LC-MS/MS relative to deuterated ISs. (C, D) BAECs were
44
incubated in media containing low (5 mM) or high (30 mM) D-glucose with 2 μM
MitoG for the times indicated. Levels of MQE (C) and QE (D) in the cell layers
were determined by LC-MS/MS relative to deuterated ISs. Results are means ±
S.E. of four independent experiments. (E) BAECs were incubated for 4 h in the
presence of 2 μM MitoG in media containing either 5 mM D-glucose (low), 35 0
mM D-glucose (high), 5 mM D-glucose/25 mM L-glucose (L-glucose), or 30 mM
D-glucose/10 mM aminoguanidinium. Levels of MQE in the cell layers were
determined by LC-MS/MS relative to deuterated ISs. Levels of MQE in the cell
layers were determined by LC-MS/MS relative to deuterated ISs. (F) BAECs were
10 incubated in media containing high (30 mM) D-glucose with 2 μM MitoG for 4 h
with the indicated concentrations of the glyoxalase I inhibitor bromobenzyl
glutathione cyclopentyl diester. Levels of MQE and QE in the cell layers were then
determined by LC-MS/MS relative to deuterated ISs. Results are means ± S.E. of
three determinations. Results are means ± S.E. of three (A, B) or four (C-E)
15 independent experiments. *, P<0.05 or ** , P<0.01, relative to untreated (A, B) or
indicated (C-E) controls; ##, P<0.01 relative to cells treated with 250 μM 1,2-
dicarbonyl.
Fig. 10. shows the quantification of mitochondrial dicarbonyls in vivo. The levels
20 of MQE (A) and QE (B) were quantified in urine of wild type and Akita mice
relative to creatinine and compared with blood glucose levels of these mice. The
data to the right of the plots are the means ± S.E. of the two conditions. ** ,
P<0.01.
25 Fig. 11. Shows the stability of MitoG under oxidative conditions.
Fig. 12. Shows the protection of MitoG against dicarbony-induced respiratory
depression and cell death.
30 Fig. 13. shows a diagram of the experimental mouse model of diabetes mellitus
Type I used for studying the effects of MitoG-amide on diabetic complications in
the heart.
Fig. 14. shows a typical magnetic resonance imaging (MRI) image of a mouse
35 heart.
45
Fig. 15. shows a typical pressure [mmHG]/volume [Wl](P/V) loop measurement
of a mouse heart.
Fig. 16. shows the effect of streptozotocin (STZ) and MitoGamide on body
weight, blood glucose and heart rate5 .
Fig. 17. shows the effect of streptozotocin (STZ) ); and STZ and MitoGamide on
mean PV-loop results.
10 Fig. 18. shows the effect of streptozotocin (STZ); and STZ and MitoGamide on
end diastolic volume (Wl); ejection fraction (%); left ventricular diastolic time
constant (Tau Weiss, ms), diastolic stiffness (1/ Wl) and end diastolic pressure
(mmHg).
15 Fig. 19. shows the effect of MitoGamide on the oxidative stress marker 4-
hydroxynonenal (4HNE).
DESCRIPTION OF THE EMBODIMENTS
Although illustrative embodiments of the invention have been disclosed in detail
20 herein, with reference to the accompanying drawings, it is understood that the
invention is not limited to the precise embodiment and that various changes and
modifications can be effected therein by one skilled in the art without departing
from the scope of the invention as defined by the appended claims and their
equivalents.
25
EXPERIMENTAL
Materials and methods
30 Chemical syntheses
A schematic of the syntheses of MitoG, quinoxaline ether (QE) and the
methylquinoxaline ethers 1 and 2 (MQE1/MQE2) is shown in Fig. 2. In summary,
6-(4-aminophenoxy)hexanol (1) was synthesized using the reported method [32].
35 Nitration of 1 was achieved as described [33] and involved conversion of 1 to the
acetamide followed by nitration with concentrated nitric acid to give 2.
Deprotection then gave the nitroaniline (3) in 48% overall yield from 1. The basic
46
o-phenylenediamine skeleton was obtained by catalytic hydrogenation of the
nitroaniline 3 over palladium on carbon. The air and light sensitive diamine (4)
was immediately protected with tert-butyloxycarbonyl (Boc) groups by treatment
with di-tert-butyldicarbonate in tetrahydrofuran [34]. The primary alcohol in 5
was mesylated to give 6 then converted to the phosphonium functional group b5 y
reaction with triphenylphosphine and sodium iodide in acetonitrile. The product
7 was obtained by precipitation from ether and column chromatography to give a
white solid in 80 % yield. In order to obtain a robust analytical sample, anion
exchange to the tetraphenylborate was carried out by treatment of 7 with sodium
10 tetraphenylborate in dichloromethane. Deprotection of the amino groups to give
MitoG was accomplished by treatment of 7 in 1,4-dioxane with 9.8 M
hydrochloric acid. MitoG was then reacted with either glyoxal to give the
quinoxaline QE, or with methyl glyoxal to give the two methylquinoxaline
products, MQE1 and MQE2, which were formed in a ratio of 10:1 (by 1H NMR)
15 although they gave a single HPLC peak. Data are quoted for the major isomer.
N-(4-(6-Hydroxyhexyloxy)-2-nitrophenyl)acetamide (2)
To a solution of 6-(4-aminophenoxy)hexan-1-ol 1 (2.12 g, 10.0 mmol) in glacial
acetic acid (3.20 mL) and water (2.40 mL) with ice (3.70 g) at 0-5 °C was added
20 acetic anhydride (1.20 mL) with rapid stirring. The resulting crystalline mixture
was dissolved by heating in a water bath. The reaction mixture was then cooled to
about 45 °C before the addition of concentrated nitric acid (1.10 mL) with stirring.
The reaction mixture was heated at 65 °C for 10 min, cooled to room temperature,
placed in an ice bath for 18 h, diluted with water and extracted into
25 dichloromethane. The organic phase was dried (MgSO4) and evaporated in vacuo
to give a mixture of 2, together with an intermediate acetate, as a yellow oil (2.98
g). Purification by column chromatography on silica gel eluting with diethyl ether
gave 2 as a yellow crystalline solid (1.279 g, 43%).
1H NMR (500 MHz, CDCl3): [ 10.03 (1H, bs, NH), 8.61 (1H, d, J = 8 Hz), 7.64
30 (1H, d, J = 2 Hz), 7.21 (1H, dd, J = 2, 8 Hz), 3.99 (2H, t, J = 6 Hz, CH2O), 3.67
(2H, t, J = 6 Hz, CH2OH), 2.26 (3H, s, Ac), 1.79-1.82 (2H, m), 1.58-1.64 (2H, m),
1.41-1.54 (4H, m), 1.30 (1H, bs, OH) ppm; 13C NMR (125 MHz, CDCl3): [ 168.8,
154.5, 137.1, 128.4, 123.9, 123.8, 109.2, 68.7 (CH2O), 62.9 (CH2OH), 32.7, 29.0,
25.9, 25.6, 25.5 ppm; MS m/z found: 319.1261, calcd. for C14H20N2O5.Na+,
35 319.1264.
6-(4-Amino-3-nitrophenoxy)hexan-1-ol (3)
47
Claisen’s alkali (0.45 mL) was added to the total crude product from 2 (0.527 g,
1.78 mmol) and heated to 70 °C with stirring for 15 min. Hot water (0.45 mL) was
then added to the reaction mixture with stirring and this was heated for another
15 min. The reaction mixture was cooled to 0-5 °C in an ice bath, diluted with
water and extracted into dichloromethane. The organic phase was dried (MgSO45 )
and evaporated in vacuo to give an orange/red solid (0.390 g). Purification by
column chromatography on silica gel eluting with diethyl ether gave 3 as an
orange/red solid (0.236 g, 52%).
1H NMR (500 MHz, CDCl3): [ 7.53 (1H, d, J = 2 Hz), 7.06 (1H, dd, J = 2, 8 Hz),
10 6.75 (1H, d, J = 8 Hz), 5.88 (2H, bs, NH2), 3.92 (2H, t, J = 6 Hz, CH2O), 3.66 (2H,
bt, J = 6 Hz, CH2OH), 1.76-1.81 (2H, m, CH2CH2O), 1.58-1.65 (2H, m,
CH2CH2OH), 1.40-1.52 (4H, m), 1.30 (1H, bs, OH); 13C NMR (125 MHz, CDCl3): [
150.3, 139.9, 131.6, 127.1, 120.1, 107.2, 68.7 (CH2O), 62.9 (CH2OH), 32.7, 29.1,
25.9, 25.6; MS m/z found: 277.1161, calcd. for C12H18N2O4.Na+: 277.1159;
15 Microanalysis found: C, 56.83, H, 6.94, N, 10.99, calcd. for C12H18N2O4: C, 56.68,
H, 7.13, N, 11.02.

CLAIMS
1. A compound of Formula 1:
A-L-5 B
Formula 1
or a pharmaceutically acceptable salt thereof, wherein:
A is a dicarbonyl sequestering moiety comprising a substituted aryl group
10 or a substituted heteroaryl group;
L is a linker moiety; and
B is a mitochondrial targeting moiety;
wherein the substituted aryl group, or the substituted heteroaryl group
15 comprises two or more substituent groups independently selected from -
NH2, -NHR1, -NR1R1, -1X-NH2, -1X-NHR1, -O-NH2, -O-NHR1, -1X-O-NH2,
-1X-O-NHR1, -NR’-NHR’, -1X-NR’-NHR’ and -NHC(O)R1; and
wherein the substituted aryl group, or the substituted heteroaryl group
20 may optionally comprise one or more optional substituent groups selected
from
-C1-6 alkyl, , -C2-6 alkenyl, -C2-6 alkynyl, -halogen, -1X-OH, -1X -O-R1, -
CO2H,
-1X-CO2H, -CO2R1, -1X-CO2R1, -1X-O-C(O)-R1, -CH(OH)-C(O)-R1, -1X25
NR1R1,
-1X-CH(OH)-C(O)-R1, -CHO, -C(O)-R1, -C(O)NH2, -C(O)NHR1, -SO2NH2
and
-SO2NHR1; and
wherein
30 each R1 is independently selected from -C1-6 alkyl, -C2-6 alkenyl,
-C2-6 alkynyl and Formula 2:
79
Formula 2
wherein each group R2-R6 is independently selected from –H, -C1-6
alkyl,
-C2-6 alkenyl, -C2-6 alkynyl, -halogen, -OH, -1X-OH, -O-C1-6 alkyl5 ,
-1X-O-C1-6 alkyl, -NR’R’, -1X-NR’R’, -1X-NH-C1-6 alkyl, -O-NH2,
-O-NH-C1-6 alkyl, -1X -O-NH2, -1X-O-NH-C1-6 alkyl, -NR’-NHR’,
-1X-NR’-NHR’, -NHC(O)-C1-6 alkyl, -O-C(O)-C1-6 alkyl, -CO2H, -1XCO2H,
10 -CO2C1-6 alkyl, -1X-CO2C1-6 alkyl, -1X-O-C(O)-C1-6 alkyl,
-CH(OH)-C(O)-C1-6 alkyl, -CHO, -C(O)-C1-6 alkyl,
-1X-CH(OH)-C(O)-C1-6 alkyl, -C(O)NH2, -C(O)NH C1-6 alkyl, -
SO2NH2 and -SO2NH C1-6 alkyl;
15 each R’ is independently selected from –H and -C1-6 alkyl; and
each 1X is independently selected from C1-6 alkylene, C2-6
alkenylene and C2-6 alkynylene.
20 2. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to claim 1, wherein A is a dicarbonyl sequestering moiety comprising a
substituted aryl group selected from substituted phenyl, biphenyl and
naphthalenyl; or a substituted heteroaryl group selected from substituted pyrrolyl,
furanyl, thiophenyl, pyrazolyl, imidazolyl, pyridinyl, pyridazinyl, pyrimidinyl,
25 chromanyl, 2-phenylchromanyl, 3-phenylchromanyl, 4-phenylchromanyl,
chromen-4-only, 2-phenylchromen-4-only, 3-phenylchromen-4-only, coumarinyl,
3-phenylcoumarinyl, 4-phenylcoumarinyl and 1,8-bis[2-chromanyl]-6-
benzo[7]annuleonyl.
30 3. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to claim 1 or 2, wherein the dicarbonyl sequestering moiety A is a
substituted aryl group of Formula 3:
80
Formula 3
wherein two or more of R7-R11 are independently selected from - -NH2,
-NHR1, -NR1R1, -C1-6 alkylene-NH2, -C1-6 alkylene-NHR1, -O-NH2, -O-NHR15 ,
-C1-6 alkylene-O-NH2, -C1-6 alkylene-O-NHR1, -NHCOR1, -NR’-NHR’ and
-C1-6 alkylene -NR’-NHR’; and
the remaining groups R7-R11 are independently selected from –H, -C1-6 alkyl,
10 -C2-6 alkenyl, -C2-6 alkynyl, -halogen, -C1-6 alkylene-OH, -C1-6 alkylene-O-R1, -CO2H,
-C1-6 alkylene-CO2H, -CO2R1, -C1-6 alkylene-CO2R1, -C1-6 alkylene-O-C(O)-R1,
-CH(OH)-C(O)-R1, -C1-6 alkylene-CH(OH)-C(O)-R1, -CHO, -C(O)-R1, -C(O)NH2,
-C(O)NHR1, -SO2NH2 and -SO2NHR1.
15 4. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to any one of the preceding claims, wherein –L- is a linker moiety of
Formula 5:
-(Z1)m-X1-Yn-[X2]s-(Z2)t-
20
Formula 5
wherein:
Z1 and Z2 are independently selected from O, NR12, NR12-C(O), C(O)NR12, O-C(O),
C(O)-O and S;
25 Y is selected from O, NR12, NR12-C(O), C(O)NR12, O-C(O), C(O)-O, S and arylene;
wherein R12 is selected from –H, -C1-C6 alkyl and -aryl;
X1 is selected from C1-Cp alkylene, C2-Cp alkenylene, C2-Cp alkynylene and C3-Cp
cycloalkylene;
X2 is selected from C1-Cq alkylene, C2-Cq alkenylene, C2-Cq alkynylene and C3-Cq
30 cycloalkylene;
each of m, n, s and t is independently selected from 0 or 1;
wherein p + q = 30 and wherein X1 and X2 are optionally substituted with one or
more functional groups independently selected from the group consisting of
81
hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl,
hydroxyalkyl, alkoxyalkyl, alkylthio, alkylsulfinyl, alkylsulfonyl, carboxyalkyl,
cyano, oxy, amino, alkylamino, aminocarbonyl, alkoxycarbonyl, aryloxycarbonyl,
alkylaminocarbonyl, arylaminocarbonyl, aralkylaminocarbonyl,
alkylcarbonylamino, arylcarbonylamino, aralkylcarbonylamino, alkylcarbonyl5 ,
heterocyclocarbonyl, aminosulfonyl, alkylaminosulfonyl, alkylsulfonyl, and
heterocyclosulfonyl, or the substituent groups of adjacent carbon atoms in the
linker group can be taken together with the carbon atoms to which they are
attached to form a carbocycle or a heterocycle.
10
5. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to claim 4, wherein –L- is a linker moiety of Formula 6:
-(Z1)m-X1-(Z2)t-
15
Formula 6.
6. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to any one of the preceding claims, wherein B is a cationic mitochondrial
20 targeting moiety or a mitochondrial targeting peptide.
7. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to any one of the preceding claims, wherein the mitochondrial
targeting moiety B is selected from:
25 (i) cationic mitochondrial targeting moieties comprising a quaternary ammonium
or phosphonium cation;
(ii) cationic mitochondrial targeting moieties comprising a 1,4a,8-triaza-
2,3,4,5,6,7-hexahydro-1H-napthalene compound; and
(iii) cationic mitochondrial targeting moieties comprising a Rhodamine
30 compound.
8. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to any one of the preceding claims, wherein B is a mitochondrial
targeting moiety of Formula 10 comprising:
35
82
Formula 10
wherein:
D is phosphorous, nitrogen or arsenic; and
each of R15, R16 and R17 is independently selected from substituted or
unsubstituted alkyl, benzyl, aryl and heteroaryl5 .
9. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to any one of the preceding claims, wherein B is a triphenylphosphonium
cation.
10
10. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to any one of the preceding claims, wherein the compound is:
(a)
; or
15 (b)
wherein An- represents an optional pharmaceutically acceptable anion.
11. A pharmaceutical composition comprising: a compound of Formula 1 or a
20 pharmaceutically acceptable salt thereof according to any one of claims 1 to 10, and
a pharmaceutically acceptable excipient, carrier or diluent.
83
12. A compound of Formula 1 or pharmaceutically acceptable salt thereof
according to any one of claims 1 to 10, for use as a medicament.
13. A compound of Formula 1 or a pharmaceutically acceptable salt thereof
according to any one of claims 1 to 10, for use in the treatment of diabetes5 ,
preferably hyperglycaemic diabetes.
14. A method of treating a disease or condition in a subject, the method
comprising administering to the subject an effective amount of a compound of
10 Formula 1, according to any one of claims 1 to 10, or a pharmaceutically acceptable
salt thereof, wherein the disease or condition is diabetes, preferably
hyperglycaemic diabetes.
15. A compound of formula 1, or a pharmaceutically acceptable salt thereof,
15 according to any one of claims 1 to 10, for use in the preservation of organ and
tissue for surgical transplants, or in the storage of blood.
16. A compound of formula 1, as defined above, or a pharmaceutically
acceptable salt thereof, according to any one of claims 1 to 10, for use in the
20 prevention or treatment of hyperglycaemia.
17. A compound of Formula 1 or a pharmaceutically acceptable salt thereof
according to any one of claims 1 to 10, for use as a mass spectrometry probe.
25 18. A method of labelling a biological molecule for mass spectrometry detection
comprising contacting said molecules with a compound according to any one of
claims 1 to 10.
19. A method according to claim 18 wherein said biological molecule comprises
30 a dicarbonyl group.