Technical Field
The present invention relates to a benzimidazole derivative, and more particularly, to a benzimidazole derivative useful as an inhibitor of human chymase activity. '
Background Art
Chymase is a neutral protease, present in mast cell granules, and is intimately involved in various biological reactions participated in by mast cells. For example, chymase has been reported to have various actions, including the promotion of degranulation from
mast cells, activation of Interleukin-l|3 (IL-1(3),
activation of matrix protease, decomposition of fibronectin and type IV collagen, promotion of the liberation of transforming growth factor-(3 (TGF-|3),
activation of substance P and vasoactive intestinal polypeptide (VIP), conversion from angiotensin I (Ang I) to angiotensin II (Ang II), and conversion of endothelin.
On the basis of the above, inhibitors of said chymase activity are considered to be promising as preventive and/or therapeutic agents against respiratory diseases such as bronchial asthma, inflammatory and allergic diseases such as allergic rhinitis, atopic dermatitis and urticaria, cardiovascular diseases such as sclerosing vascular lesions, vasoconstriction, peripheral circulatory disorders, renal insufficiency and cardiac insufficiency, and bone and cartilage metabolic diseases such as rheumatoid arthritis and osteoarthritis.
Although known examples of chymase activity inhibitors of the prior art include a triazine derivative (Japanese Unexamined Patent Publication No. 8-208654),
hydantoin derivative (Japanese Unexamined Patent Publication No. 9-31061), imidazolidine derivative (International Publication No. WO96/04248), quinazoline derivative (International Publication No. W097/11941), heterocyclic amide derivative (International Patent Publication No. W096/33974), cefam compound (Japanese Unexamined Patent Publication No. 10-087493), phenol derivative (Japanese Unexamined Publication No. 10-087567), heterocyclic amide compound (International Publication No. W098/18794), acetoamide derivative (International Publication No. WO98/09949), heterocyclic amide^compound (Japanese Unexamined Publication No. 10-007661), acid anhydride derivative (Japanese Unexamined Patent Publication No. 11-049739), heterocyclic amide compound (International Publication No. W099/32459) and acetoamide derivative (International Publication No. W099/41277), these compounds and the compound of the present invention are completely different structurally.
The chymase inhibitor compounds disclosed thus far have lacked usefulness as a result of having inadequate activity or being structurally unstable. However, the compound of the present invention has extremely high activity and demonstrates superior kinetics in the blood, making it highly useful as a drug.
On the other hand an example of a technology related to the compound of the present invention is described in the specification of US Patent No. 5124336. A benzimidazole derivative is described in said specification as a compound that has thromboxane receptor antagonistic activity. However, the compound described in said specification is not disclosed as having a heteroaryl group substituted in the benzimidazole skeleton, and there is also no description of human chymase activity of said compound. In addition, although a benzimidazole compound is also described as an antitumor agent in Japanese Unexamined Patent Publication No. 01-265089, there is no mention of human chymase
inhibitory activity.
Disclosure of the Invention
The object of the present invention is to provide a novel compound capable of being a human chymase activity inhibitor that can be applied clinically.
As a result of repeated and earnest research to achieve the above: object, the inventors of the present invention found a benzimidazole derivative or its medically acceptable salt, represented by the following formula (1), that has a structure that is completely different from known compounds, thereby leading to. completion of the present invention:
(Formula Removed)
wherein, R1 and R2 may be the same or different and each independently represents a hydrogen atom, a halogen atom, a trihalomethyl group, a cyano group, a hydroxy1 group, an alkyl group having 1-4 carbon atoms, an alkoxy group having 1-4 carbon atoms, or R1 and R2 together represent -0-CH2-0-, -0-CH2CH2-0- or -CH2CH2CH2- (these groups may be subst itu"te"d by one or more alky regroups having 1-4 carbon atoms);
A represents a substituted or unsubstituted, linear, cyclic or branched alkylene or alkenylene group having 1-7 carbon atoms which may be interrupted by one or more of -0-, -S-, -S02- and -NR3- (where. R3 represents a hydrogen atom or linear or branched alkyl group having 1-6 carbon atoms); the substituent that can be possessed by these groups is selected from a halogen atom, hydroxyl group, nitro group, cyano group, linear or branched alkyl group having 1-6 carbon atoms, linear or branched alkoxy group having 1-6 carbon atoms (including the case in which two adjacent groups form an acetal bond, namely including the
case in which the alkyl portions of geininal two alkoxy groups are connected to form a ring), a linear or branched alkylthio group having 1-6 carbon atoms, a linear or branched alkylsulfonyl group having 1-6 carbon atoms, a linear or branched acyl group having 1-6 carbon atoms, a linear or branched acylamino group having 1-6 carbon atoms, a trihalomethyl group, a trihalomethoxy group, a phenyl group, an oxo group, and a phenoxy group that, may be substituted by one or more halogen atoms; and, one or more of these substituents may each independently be bonded to optional positions of the alkylene or alkenylene group;
E represents a -COOR3, -S03R3, -CONHR3, -S02NHR3, tetrazole-5-yl group, a 5-oxo-l,2,4-oxadiazole-3-yl group or a 5-oxo-l,2,4-thiadiazole-3-yl group (where R3 is as defined above);
G represents a substituted or unsubstituted, linear or branched alkylene group having 1-6 carbon atoms which may be interrupted by one or more of -0-, -S-, -S02- and -NR3- (where, R3 is as defined above. Where these atoms or atomic groups exist, they are not bonded directly to the benzimidazole ring.); and, the substituent that can be possessed by said alkylene group is selected from a halogen atom, a hydroxyl group, a nitro group, a cyano group, a rinearr or brancheda±kylr"group having 1-6 carbon atoms, a linear or branched alkoxy group having 1-6 carbon atoms (including the case in which two adjacent groups form an acetal bond), a trihalomethyl group, a trihalomethoxy group, a phenyl group, and an oxo group;
M represents a single bond or -S(0)m-, where m is an integer of 0-2;
J represents a substituted or unsubstituted heterocyclic group having 4-10 carbon atoms and containing one or more hetero atoms selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom on its ring, with the proviso that an imidazole ring is excluded; the substituent that can be
possessed by said aromatic hetetrocyclic group is selected from a halogen atom, a hydroxyl group, a nitro group, a cyano group, a linear or branched alkyl group having 1-6 carbon atoms, a linear or branched alkoxy group having 1-6 carbon atoms (including the case in which two adjacent groups form an acetal bond), a linear or branched alkylthio group having 1-6 carbon atoms, a linear or branched alkylsulfonyl group having 1-6 carbon atoms, a linear or branched acyl group having 1-6 carbon atoms, a linear or branched acylamino group having 1-6 carbon atoms, a substituted or unsubstituted anilide group, a trihalomethyl group, a trihalomethoxy group, a phenyl group, an oxo group, a COOR3 group, and a phenoxy group that may be substituted by one or more halogen atoms; and, one or more of these substitutents may be substituted at optional positions on the ring; and,
X represents a methine group (-CH=) or nitrogen atom.
Best Mode for Carrying Out the Invention
The substituents in the compound of the present invention represented by the above formula (1) are as indicated below.
R1 and R2 may be the same or different and each in depend errtly repres ents a hydrogen atom,a halogen a torn, trihalomethyl group, a cyano group, a hydroxyl group, an alkyl group having 1-4 carbon atoms, an alkoxy group having 1-4 carbon atoms. Alternatively, R1 and R2 together represent -0-CH2-0-, -0-CH2CH2-0- or -CH2CH2CH2-, and in this case, these groups may be substituted by one or more alkyl groups having 1-4 carbon atoms.
Specific examples of the alkyl groups having 1-4 carbon atoms as R1 and R2 include a methyl group, an ethyl group, an n- or i-propyl group and an n-, i-, s- or t-butyl group. A preferable example is a methyl group. Specific examples of alkoxy.groups having 1-4 carbon atoms include a methoxy group, an ethoxy group, an n- or
i-propoxy group and an n-, i-, s- or t-butoxy group.
Preferable examples of R1 and R2 include a hydrogen atom, a halogen atom, a trihalomethyl group, a cyano group, a hydroxyl group, an alkyl group having 1-4 carbon atoms and an alkoxy group having 1-4 carbon atoms. More preferable examples include a hydrogen atom, a halogen atom., a trihalomethyl group, a cyano group, an alkyl group having 1-4 carbon atoms and an alkoxy group having 1-4 carbon atoms, still more preferable examples include a hydrogen atom, chlorine atom, a fluorine atom, a trifluoromethyl group, methyl group, a methoxy group and an ethoxy group, while particularly preferable examples include a hydrogen atom, a methyl group and a methoxy group.
A represents a substituted or unsubstituted, linear, cyclic or branched alkylene or alkenylene group having 1-7 carbon atoms. Examples of the unsubstituted, linear, cyclic or branched alkylene group having 1-7 carbon atoms include a methylene group, an ethylene group, an n- or i-propylene group, a 2,2-dimethylpropylene group, an n-, i-or t-butylene group, a 1,1-dimethylbutylene group, an n-pentylene group and a cyclohexylene group. More preferable examples include an ethylene group, an n-propylene group, a 2,2-dimethylpropylene group and an n-
or t butylene group.Stri 11 more preferalrle examples
include an n-propylene group and a 2,2-dimethylpropylene group. A particularly preferable example is an n-propylene group. Examples of the unsubstituted linear or branched alkenylene group having 1-7 carbon atoms include a vinylene group, a propenylene group, a butenylene group and a pentenylene group.
Although said alkylene group or alkenylene group may be interrupted by one or more of -0-, -S-, -S02- and -NR3- (where R3 represents a hydrogen atom or linear or branched alkyl. group having 1-6 carbon atoms), these atoms or atomic groups are not bonded directly to M. Specific examples include interrupted ethylene groups, n-
propylene groups or n- or t-butylene groups. More specific examples include -CH2OCH2-, -CH2OCH2CH2-, -CH2SCH2-, -CH2SCH2CH2-, -CH2S02CH2-, -CH2S02CH2CH2-, -CH2NR4CH2- and -CH2NR*CH2CH2-. Preferable examples include -CH2OCH2-, -CH2SCH2- and -CH2S02CH2-. '
The substituent groups that can be possessed by said alkylene group is selected from a halogen atom, a hydroxyl group, a nitro group, a cyano group, a linear or branched alkyl group having 1-6 carbon atoms, a linear or branched alkoxy group having 1-6 carbon atoms (including the case in which two adjacent groups form an acetal bond}, .a linear or branched alkylthio group having 1-6 carbon atoms, a linear or branched alkylsulfonyl group having 1-6 carbon atoms, linear or branched acyl group having 1-6 carbon atoms, a linear or branched acylamino group having 1-6 carbon atoms, a trihalomethyl group, a trihalomethoxy group, a phenyl group, an oxo group, and a phenoxy group that may be substituted by one or more halogen atoms. One or more of these substituents may each be independently bonded to optional positions of the alkylene group or alkenylene group.
Examples of the halogen atom include a fluorine
atom, a chlorine atom, a bromine atom and an iodine atom.
Preferable examples are a fluorine atom and a chlorine
atom:.
Specific examples of the linear or branched alkyl group having 1-6 carbon atoms include a methyl group, an ethyl group, an n- or i-propyl group and an n-, i-, s- or t-butyl group, while preferable examples are a methyl group and an ethyl group. A more preferable example is a methyl group.
Specific examples of the linear or branched alkoxy group having 1-6 carbon atoms include a methoxy group, an ethoxy group, an n- or i-propoxy group and an n-, i-, s-or t-butoxy group, while preferable examples are a methoxy group and an ethoxy group. A more preferable example is a methoxy group.
Specific examples of the linear or branched alkylthio group having 1-6 carbon atoms include a methylthio group, an ethylthio group, an n- or i-propylthio group, and an n-, i-, s- or t-butylthio group, and preferable examples are a methylthio group and an ethylthio group. A more preferable example is a methylthio group.
Specific examples of the linear or branched alkylsulfonyl group having 1-6 carbon atoms include a methylsulfonyl group, an ethylsulfonyl group, an n- or i-propylsulfonyl group and an n-, i-, s- or t-butylsulfonyl group, and preferable examples are a methylsulfonyl group and an ethylsulfonyl group. A more preferable example is a methylsulfonyl group.
Examples of the linear or branched acyl group having 1-6 carbon atoms include an acetyl group, an ethylcarbonyl group, an n- or i-propylcarbonyl group and an n-, i-, s- or t-butylcarbonyl group, and preferable examples are an acetyl group and an ethylcarbonyl group. A more preferable example is an acetyl group.
Specific examples of the linear or branched acylamino group having 1-6 carbon atoms include an acetylamino group, an ethylcarbonylamino group, an n- or i-propylcarbonylamino group and an n-, i-, s- or t-butylcrarbony±amrno- group,—and-pre-ferable examples are an acetylamino group and an ethylcarbonylamino group. A more preferable example is an acetylamino group.
Specific examples of the trihalomethyl group are a trifluoromethyl group, a tribromomethyl group and a trichloromethyl group. A preferable example is a trifluoromethyl group.
In particular, A is preferably a substituted or unsubstituted, linear, cyclic or branched alkylene group having 1-7 carbon atoms {although it may be interrupted by one or more of -0-, -S-, -S02- and -NR3- (where NR3 is as defined above), these atoms or atomic groups not being bonded directly to M}. Preferable examples include
-CH2CH2-, -CH2CH2CH2-, -CH2C ( =0 ) CH2-, -CH20CH2- , -CH2SCH2-, -CH2S(=0)CH2-, -CH2CF2CH2-, -CH2S02CH2-, -CH2CH2CH2CH2-, -CH2C(CH3)2CH2-/ -CH2S02CH2CH2-, -CH2C (=0 ) CH2CH2- , -CH2C (=0) (CH3) 2CH2-, and -CH2C (=0) C (=0) CH2- . More preferable examples are -CH2CH2-, -CH2CH2CH2-, -CH2C(=0)CH2-, -CH20CH2-, CH2SCH2-, -CH2S ( =0 ) CH2-, -CH2CF2CH2-, -CH2S02CH2- and -CH2C (CH3)2CH2-. Still more preferable examples are -CH2CH2-, -CH2CH2CH2- and -CH2C(CH3)2CH2-. A particularly preferable example is
E represents a -C00R3, -S03R3, -CONHR3, -S02NHR3, tetrazole-5-yl, 5-oxo-l,2,4-oxadiazole-3-yl or 5-oxo-1, 2,4-thiadiazole-3-yl group (where, R3 represents a hydrogen atom, or linear or branched alkyl group having 1-6 carbon atoms).
Examples of R3 include a hydrogen atom, a methyl group, an ethyl group, an n- or i-propyl group and an n-, i-, s- or t-butyl group. Preferable examples are a hydrogen atom, a methyl group and an ethyl group. A particularly preferable example is a hydrogen atom.
In particular, preferable examples of E are -C00R3, -S03R3, and tetrazole-5-yl groups. A more preferable example is a -C00R3 group. A particularly preferable example is a -C00H group.
"" "~ G -represents~a—substitutedor unsubstituted, linear or branched alkylene group having 1-6 carbon atoms which may be interrupted by one or more of -0-, -S-, -S02- and -NR3-. Here, R3 is as defined above. In addition, in the case of containing these hetero atoms or atomic groups, they are not directly bonded to the benzimidazole ring. The substituent that can be possessed by the alkylene group is selected from a halogen atom, a hydroxyl group, a nitro group, a cyano group, a linear or branched alkyl group having 1-6 carbon atoms, a linear or branched alkoxy group having 1-6 carbon atoms (including the case in which two adjacent groups form an acetal bond), a trihalomethyl group, a trihalomethoxy group, a
phenyl group and an oxo group. Specific examples of G include -CH2-, -CH2CH2-, -CH2CO-, -CH2CH20-, -CH2CONH-, -CO-, -S02-, -CH2S02-, -CH2S- and -CH2CH2S-, while preferable examples are -CH2-, -CH2CH2-, -CH2CO- and -CH2CH20-. More preferable examples are -CH2- and -CH2CH2-, and a particularly preferable example is -CH2-. These groups are bonded on the left hand side to position 1 (N atom) of the benzimidazole ring, while on the right hand side to J.
M represents a single bond or -S(0)m-, where m represents an integer of 0-2. Preferable examples of M are -S- and -S02-. A particularly preferable example is -S-.
J represents a substituted or unsubstituted heterocyclic group having 4-10 carbon atoms and containing one or more hetero atoms selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom on its ring. However, an imidazole ring is excluded. In addition, J is limited to that which can be chemically synthesized.
Specific examples of the unsubstituted heterocyclic groups having 4-10 carbon atoms and containing one or more hetero atoms on -its ring selected from the group consisting of an oxygen atom, a nitrogen atom and a "S'urf"ur~artom TbTc±trde—a pyridyl -group,a furyl- group, a thienyl group, a thiazolyl group, a pyrimidinyl group, an oxazolyl group, an isooxazolyl group, a benzofuryl group, a benzimidazolyl group, a quinolyl group, an isoquinolyl group, a quinoxalinyl group, a benzoxadiazolyl group, a benzothiaziazolyl group, an indolyl group, a benzothiazolyl group, a benzothienyl group and a benzoisooxazolyl group. A preferable example is a bicyclic heterocyclic ring. More preferable examples are a benzofuryl group, a benzoimidazolyl group, a quinolyl group, an isoquinolyl group, a quinoxalinyl group, a benzoxadiazolyl group, a benzothiazolyl group, an indolyl group, a benzothiazolyl group, a benzothienyl group and a
benzoisooxazolyl group, while a particularly preferable example is a benzothienyl group or an indolyl group.
The substituent groups that can be possessed by the aromatic heterocyclic group is selected from a halogen atom., a hydroxyl group, a nitro group, a cyano group, a linear or branched alkyl group having 1-6 carbon atoms, a linear or branched alkoxy group having 1-6 carbon atoms (including the case in which two adjacent groups form an acetal bond), a linear or branched alkylthio group having 1-6 carbon atoms, a linear or branched alkylsulfonyl group having 1-6 carbon atoms, a linear or branched acyl group having 1-6 carbon atoms, a linear or branched acylamino group having 1-6 carbon atoms, a substituted or unsubstituted anilide group, a trihalomethyl group, a trihalomethoxy group, a phenyl group, and a phenoxy group that may be substituted by one or more halogen atoms. One or more of these substituents groups may each independently be bonded to optional positions of the ring.
Examples of the halogen atom are a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Preferable examples are a fluorine atom and a chlorine atom „
Specific examples of the linear or branched alkyl groups having-1-6—carbon -atoms- irnciude a -methyl group, an ethyl group, an n- or i-propyl group and an n—, i-, s- or t-butyl group, and preferable examples are a methyl group and an ethyl group. A more preferable example is a methyl group.
Specific examples of the linear or branched alkoxy groups having 1-6 carbon atoms include a methoxy group, an ethoxy group, an n- or i-propyloxy group, an n-, i-, s- or t-butyloxy group and a methylenedioxy group, and preferable examples are a methoxy group and an ethoxy group. A more preferable example is a methoxy group.
Specific examples of the linear or branched alkylthio group having 1-6 carbon atoms include a
methylthio group, an ethylthio group, an n- or i-propylthio group and an n-, i-, s- or t-butylthio group, and preferable examples are a methylthio group and an ethylthio group. A more preferable example is a methylthio group.
Specific examples of the linear or branched alkylsulfonyl group having 1-6 carbon atoms include a methylsulfonyl group, an ethylsulfonyl group, an n- or i-propylsulfonyl group and an n-, i-, s- or t-butylsulfonyl group, and preferable examples are a methylsulfonyl group and an ethylsulfonyl group. A more preferable example is a methylsulfonyl group.
Specific examples of the linear or branched acyl group having 1-6 carbon atoms include an acetyl group, an ethylcarbonyl group, an n- or i-propylcarbonyl group and an n-, i-, s- or t-butylcarbonyl group, and preferable examples are an acetyl group and an ethylcarbonyl group. A more preferable example is an acetyl group.
Specific examples of the linear or branched acylamino group having 1-6 carbon atoms include an acetylamino group, an ethylcarbonylamino group, an n- or i-propylcarbonylamino group and an n-, i-, s- or t-butylcarbonylamino group, and preferable examples are an acetylamino group and an ethylcarbonylamino group. A more preirerairfreexample is an -acetyl-amino group.
Specific examples of the trihalomethyl group include a trifluoromethyl group, a tribromomethyl group and a trichloromethyl group.
X represents a -CH= group or nitrogen atom, and a preferable example is a -CH= group.
Preferable examples of the compounds represented by the above formula (1) include various groups of compounds composed by combining each of the groups previously described as preferable examples. Although there is no intention of limiting these groups, those described in the following table are particularly preferable. In particular, preferable examples of those compounds in the
table include compound Nos. 34, 38, 39, 41, 42, 52, 54, 56, 58, 59, 63, 135, 137, 148, 152, 154, 244, 340, 436, 514, 519, 521, 532, 534, 536, 538, 615, 628, 1112 and 1114.
Furthermore, Al through A3 and Jl through J32 in the following table are groups represented with the following formulas. In the formulas, although E, G, M, m and X are as defined above, they are described hereinbelow using representative examples, namely E is COOH, G is CH2, M is S (m being 0) or a single bond (indicated with "-" in the table) and X is -CH=. However, it is not intended that the present invention is limited to these compounds.
(Table Removed)The benzimidaz-ole derivative (1) of the present invention can be produced by synthesis method (A) or
synthesis method (B) shown below in the case E is COOR3 and M is S:
Synthesis Method (A)
(Formula Removed)wherein, Z represents a halogen or ammonium group, and R1, R2, R3, A,- G, J and X are as defined above.
Namely, an orthophenylenediamine compound (a2) is obtained by reducing the nitro group of a 2-nitroaniline derivative (al). After reacting this with CS2 and obtaining compound (a3), it is reacted with a halide ester derivative (a4) to obtain (a5) followed by further reacting with a halide derivative or ammonium salt (a6) to be able to obtain the compound (a7) of the present invention. In addition, benzimidazole derivative (a8), in which R3 is a hydrogen atom, can be obtained by hydrolyzing this as necessary.
Reduction of the nitro group can be carried out, in accordance with the conditions of an ordinary catalytic reduction, by reacting with hydrogen gas at a temperature of room temperature to 100°C in the presence of a catalyst such as Pd-C Under acidic, neutral or alkaline conditions. In addition, this can also be carried out by a method in which treatment is carried out using zinc or tin under acidic conditions, or by a method that uses zinc powder under neutral or alkaline conditions.
The reaction between orthophenylenediamine derivative (a2) and CS2 can be carried out according to the method described in, for example, The Journal of Organic Chemistry (J. Org. Chem.), 1954, Vol. 19, pages 631-637 (pyridine solution) or in The Journal of Medical Chemistry (J. Med. Chem.), 1993, Vol. 36, pages 1175-1187
(ethanol solution).
The reaction between thiobenzimidazole compound (a3) and halide ester (a4) can be carried out by agitating at a temperature of 0°C-200°C in the presence of a base such as NaH, Et3N, NaOH or K2C03 in accordance with the conditions of an ordinary S-alkylation reaction.
The reaction between thiobenzimidazole compound
9) and stirring. The inside of the reaction vessel was replaced with hydrogen gas followed by stirring for 20 hours at room temperature in a hydrogen gas atmosphere. After filtering the reaction solution with Celite, the filtrate was concentrated to obtain 30 g of a black solution. This was then purified by silica gel column chromatography (hexane:ethyl acetate = 10:1) to obtain 11.33 g (86 mmol) of the target compound (yield of the two steps: 67%). Confirmation of the compound was carried out by identifying using 1H-NMR.
"H-NMR (270 MHz, CDC13) (ppm): 7.28-7.07 (m,3H), 6.93 (m,lH), 6.57 (m,lH), 2.57 (s,3H)
Step 2
Production of 1,4-dimethylindole
(Formula Removed)12.7 g (134 mmol) of t-butoxypotassium and 80 ml of N,N-dimethylformamide were added to a pre-dried reaction vessel. 8.9 g (67.9 mmol) of the 4-methylindole obtained in Step 1 were added followed by stirring for 35 minutes at room temperature. 15.8 g (13 4 mmol) of dimethyl oxalate were added to this followed by stirring for 5 hours and 30 minutes at 120°C. After concentrating under
reduced pressure, 200 ml of water were added followed by treatment with 1 M hydrochloric acid to make acidic (pH = 3) followed by extraction with ethyl acetate (200 ml x 2) and drying with anhydrous magnesium sulfate. After distilling off the solvent under reduced pressure, it was purified by silica gel column chromatography (hexane:ethyl acetate = 5:1) to obtain 9.24 g (53 mmol) of the target compound (yield: 94%). Confirmation of the compound was carried out by identifying-using ^-H-NMR.
"H-NMR (270 MHz, CDCl3) (ppm): 7.25-7.09 (m,2H), 7.03 (m,lH), 6.90 (m,lH), 6.49 (m,lH), 3.78 (s,3H), 2.55 (s,3H)
Step 3
Production of 1,4-dimethyl-3-(N,N-
dimethylaminomethvl)indole
(Formula Removed)5.9 ml (72.0 mmol) of 37% aqueous formaldehyde solution and 7.08 ml (78 mmol) of 50% aqueous dimethylamine solution were sequentially added to a mixed system containing- 25 ml each of 1,4-dioxane and acetic acid. After cooling to room temperature, as this reaction generates heat, 10- ml of a 1,4-dioxane solution containing 9.24 g (63.6 mmol) of the 1,4-dimethylindole obtained in Step 2 were added followed by stirring for 2 hours at room temperature. The reaction solution was then concentrated as is. 5 M aqueous sodium hydroxide solution were then added to the residue to make alkaline (pH = 12) and bring to a total volume of 100 ml followed by extraction with ethyl acetate (100 ml x 2). The organic phase was then dried with anhydrous magnesium sulfate and concentrated under reduced pressure to obtain 12.93 g (63.9 mmol) of the target compound (crude yield: 100.4%). Confirmation of the compound was carried out by identifying using 1H-NMR.
'H-NMR (270 MHz, CDC13) (ppm): 7.15-7.06 (m,2H), 6.91 (m,lH), 6.85 (m,lH), 3.71 (s,3H), 3.59 (s,2H), 2.74 (s,3H), 2.27 (s,6H)
Step 4
Production of ((1,4-dimethvlindole-3-
y1)methyl)trimethylammonium iodide
(Formula Removed)
12.93 g (63.6 mmol) of the 1,4-dimethyl-3-(N,N-dimethylaminornethyl) indole obtained in Step 3 were dissolved in 6 0 ml of ethanol followed by the addition of 4.36 ml (70 mmol) of methyl iodide. A white precipitate formed after stirring for 2 hours at room temperature. This was then filtered, washed twice with 10 ml of ethanol and dried in a vacuum to obtain 16.66 g (48.4 mmol) of the target compound (yield of the two steps: 76%). Confirmation of the compound was carried out by identifying using 1H-NMR.
'H-NMR (270 MHz, DMSO) (ppm): 7.65 (s,lH), 7.36 (d,lH), 7.13 (t,lH), 6.91 (d,lH), 4.74 (s,2H), 3.82 (s,3H), 3.01 (s,9H), 2.65 (s,3H)
[Reference Example 7]
Production of 4-(5-methoxybenzimidazole-2-
ylthio)butanoate ester hydrogen bromide salt
(Formula Removed)6.48 g (33.2 mmol) of 4-bromobutanoate ethyl ester were added to 10 ml of an ethanol solution containing 5.0 g (27.7 mmol) of 5-methoxybenzimidazole-2-thiol followed by .stirring for 1 hour at 80°C and adding 90 ml of ethyl acetate. The reaction solution was returned to room temperature and the formed crystals were filtered out followed by drying to obtain 9.34 g of the target compound (yield: 90%).
'H-NMR (270 MHz, CDCl3) (ppm): 7.65 (d,lH,J=8.91 Hz), 7.24 (s,lH), 7.00 (dd,1H,J=2.43, 8.91 Hz), 4.21 (q,2H,J=7.29 Hz), 3.83 (s,3H), 3.74 (m,2H), 2.61 (m,2H), 2.10 (m,2H), 1.30 (t,3H,J=7.29 Hz)
[Example 1]
Production of Compound No. 3 9
(Formula Removed)480 mg (2.49 mmol) and 10 ml of tetrahydrofuran were added to a pre-dried reaction vessel. 505 mg (1.91 mmol) of the 4-(benzimidazole-2ylthio)butanoate ethyl ester obtained in Reference Example 3 and 724 mg (2.10 mmol) of ((1,4-dimethylindole-3-yl)methyl)trimethylammonium iodide were added followed by stirring for 6 hours at 80°C. After filtering the solution by passing through Celite, it was concentrated under reduced pressure. The residue was then purified by silica gel column chromatography (dichloromethane:ethyl acetate = 8:1) to obtain 540 mg (1.28 mmol) of'4-(1-((1,4-dimethylindole-3-yl)methyl)benzimidazole-2-ylthio)butanoate ethyl ester (yield: 67%).
2.0 ml of a 2M aqueous sodium hydroxide solution were then added to 6 ml of a methanol solution containing 540 mg (1.28 mmol) of the resulting 4-(l-((l,4-dimethylindole-3-yl)methyl) benzimidazole-2-ylthio)butanoate ethyl ester. After stirring for 16 hours at room temperature, 6 M hydrochloric acid was added to stop the reaction. The solvent was removed to a certain degree by concentration under reduced pressure followed by extraction with ethyl acetate. After washing the ethyl acetate phase with saturated brine, it was dried with anhydrous magnesium sulfate. After distilling off the solvent under reduced pressure, it was purified
by silica gel column chromatography
(dichloromethane:methanol = 8:1) to obtain 5 02 mg (1.28 mmol) of the target compound (yield: 100%). Confirmation of the compound was carried out by identifying from its molecular weight using LC-MS.
Calculated value M = 393.15, Measured value (M+H)+ = 394.2
[Example 2]
The following compounds and the compounds in the following table were synthesized according to the same method as Example 1 using the compounds indicated in Reference Example 2 or 3 as well as various quaternary ammonium salts or halide derivatives synthesized with reference to Reference Examples 4-6 and other references described in the text. Confirmation of the compounds was carried out by identifying from their molecular weights using LC-MS. However, some of the compounds were synthesized using conditions that somewhat differed from those of Example 1, including conditions such as the use of DMF and so forth for the solvent and the use of porassium carbonate for the base in coupling, the use of THE and EtOH for the solvent in hydrolysis, and the use of a temperature of room temperature to 5 0°C.
In addition, the following compounds were similarly synthesized.
4-(1-(2-(l-methylindole-3-yl)ethyl)benzimidazole-2-
ylthio)butanoic acid (Compound No. 1153)
In this case however, a methanesulfonate ester of 2-(l-methylindole-3-yl)ethanol was used instead of quaternary ammonium salt and halide derivative. Identification of the compound was carried out using LC-MS. The yield was 19% (two steps of N-alkylation and ester hydrolysis).
Calculated value M = 393.15, Measured value (M+H)+ = 394.0
4-(l-(4-methvl-7-chlorobenzo[bjthiophene-3-
yl)methyl)benzimidazole-2-ylthio)butanoic acid
(Compound No. 1154'i
Yield: 15% (two steps of N-alkylation and ester hydrolysis)
Calculated valve M = 430.06, Measured value (M+H)+ = 431.2
'H-NMR (270 MHz, DMSO-d6) (ppm): 12.17 (br,lH), 7.63 (d,lH,J=7.83 Hz), 7.47-7.40 (m,2H), 7.26 (d,lH,J=8.10 Hz), 7.22-7.11 (m,2H), 6.46 (s,lH), 5.86 (s,2H), 3.34 (t,2H,J=7.29 Hz), 2.84 (S,3H), 2.34 (t,2H,J=7.29 Hz), 1.94 (m,2H)
4-( l-(4-methvl-7-bromobenzo|"b1thiphene-3-
yl)methyl)benzoimidazole-2-vlthio)butanoic acid
(Compound No. 1155)
Yield: 56% (two steps of N-alkylation and ester hydrolysis)
Calculated value M = 474.01, Measured value (M+H)+ = 4 7 7.0
^-NMR (270 MHz, DMS0-d6) (ppm): 12.18 (br,lH), 7.63 (d,lH,J=7.56 Hz), 7.53 (d,lH,J=7.56 Hz), 7.46 (d,lH,J=7.56 Hz), 7.22-7.11 (m,3H), 6.46 (s,lH), 5.85 (s,2H), 3.34 (t,2H,J=7.29 Hz), 2.83 (s,3H), 2.34 (t,2H,J=7.29 Hz), 1.97 (m,2H)
[Example 3]
Production of Compound No. 148
Step 1
Production of f(benzothiophene-3-yl)methylW4-
methoxy-2-nitrophenyl)amine
(Formula Removed)740 mg (2.8 mmol) of 4-methoxy-2-nitrotrifluoroanilide were dissolved in 5 ml of dimethylformamide followed by the sequential addition of
503 mg (3.64 mmol) of potassium carbonate and 773 mg (3.4 mmol) of 3-bromomethylbenzothiophene and heating to 100°C. After 12 hours, 5 ml of 5 M aqueous sodium hydroxide solution were added and refluxed, as is, for 1 hour. After 15 minutes, the solution was cooled to room temperature followed by the addition of 10 ml of water and extraction with chloroform. After washing the organic phase twice with 25 ml of saturated brine and drying with magnesium sulfate, it was concentrated and dried under reduced pressure. The residue was then purified by silica gel column chromatography (hexane:ethyl acetate = 60:1) to obtain 400 mg of ((benzothiophene-3-yl)methyl)(4-methoxy-2-nitrophenyl)amine in the form of an orange powder (yield: 44%) .
Step 2
Production of 1-((benzothiophene-3-yl)methyl)-5-
methoxybenzoimidazole-2-thiol
(Formula Removed)4 ml of ethanol and 4 ml of 1,4-dioxane were added to 400 mg (1.23 mmol) of ((benzothiophene-3-yl)methyl)(4-methoxy-2-nitrophehyl)amine followed by the addition of 0.3 4 ml of 5 M aqueous sodium hydroxide solution and refluxing while heating. After 15 minutes, the reaction solution was removed from the oil bath followed by the divided addition of 320 mg (4.9 mmol) of zinc powder. The reaction solution was again refluxed while heating for 1 hour. After allowing to cool to room temperature, the zinc was filtered out and the filtrate was concentrated under reduced pressure followed by extraction with chloroform. The organic phase was washed twice with 5 ml of saturated brine followed by drying
with magnesium sulfate, concentration under reduced pressure and drying to obtain 309 mg of a brown oil.
Continuing, the resulting brown oil was dissolved in 10 ml of ethanol followed by the addition of 2.5 ml (42 mmol) of carbon disulfide and refluxing. After 12 hours, the reaction solution was returned to room temperature and concentrated under reduced pressure followed by the addition of 2 ml of ethanol and irradiating with ultrasonic waves to break into fine fragments that were then filtered. The resulting powder was washed twice with 2 ml of ethanol and then dried to obtain 12 0 mg (0.37 mmol) of l-((benzothiophene-3-yl)methyl)-5-methoxybenzimidazole-2-thiol (yield of the two steps: 30%) .
Step 3
Production of 4- (1- ( (benzothiophene--3-yl) methyl) -5-
methoxybenzimidazole-2-ylthio)butanoate ethyl ester
(Formula Removed)101 mg (0.30 mmol) of 1-((benzothiophene-3-yl)methyl)-5-methoxybenzimidazole-2-thiol were dissolved in 2 ml of dimethylfprmamide. followed by the addition of 62 mg (0.45 mmol) of potassium carbonate and 53 mg (0.40 mmol) of 4-bromobutanoate ethyl ester and heating to 80°C. After 12 hours, the reaction solution was concentrated under reduced pressure and extracted with diethyl ether followed by washing twice with 10 ml of saturated brine and drying with magnesium sulfate. The solvent was then concentrated under reduced pressure and the residue was purified by silica gel column chromatography (hexane:ethyl acetate = 1:1) to obtain 6 0 mg (0.136 mmol) of 4-(1-((benzothiophene-3-yl)methyl)-5-methoxybenzimidazole-2-ylthio)'butanoate ethyl ester (yield: 45%).
Step 4
Production of 4-(1-((benzothiophene-3-yl)methyl)-5-
methoxybenzimida2ole-2-ylthio)butanoic acid
(Formula Removed)60 mg (0.136 mmol) of 4-(1-((benzothiophene-3-yl)methyl)-5-methoxybenzimidazole-2-ylthio)butanoate ethyl ester were dissolved in 2 ml of methanol followed by the addition of 0.5 ml of 4 M aqueous sodium hydroxide solution. After stirring for 3 hours at 50°C, 6 M hydrochloric acid was added to stop the reaction followed by concentrating under reduced pressure and extracting with chloroform. After washing the organic phase with saturated brine, it was dried with anhydrous magnesium sulfate. The solvent was concentrated under reduced pressure and the residue was purified by silica gel column chromatography (ethyl acetate) to obtain 2 0 mg (0.048 mmol) of the target compound (yield: 36%). Confirmation of the compound was carried out by identifying from the molecular weight using LC-MS.
Calculated value M = 412.09, Measured value (M+H)+ = 413.1
[Example 4]
Production of Compound No. 135
The target compound was obtained according to the same method as Example 3.
However, ((1,4-dimethylindole-3-yl)methyl) trimethylammonium iodide was used in the reaction corresponding to Step 1.
Confirmation of the compound was carried out by identifying from the molecular weight using LC-MS.
Calculated value M = 423.16, Measured value (M+H)+ = 424.3
Production of Compound No. 13 7
The target compound was obtained according to the
same method as Example 3.
However, ((l-methyl-4-chloroindole-3-yl)methyl) trimethylammonium iodide was used in the reaction corresponding to Step 1.
Confirmation of the compound was carried out by identifying from the molecular weight using LC-MS.
Calculated value M = 443.11, Measured value (M+H)+ = 444.3
[Example 5]
Production of Compound No. 2 44
The target compound was obtained using the same method as Example 3. However, 4-cyano-2-nitrotrifluoroacetonitrile was used as the reagent corresponding to Step 1. In addition, the step in which the 2-nitroaniline derivative is reduced to an orthophenylenediamine derivative, and the step in which this is cyclized to a benzimidazole-2-thiol derivative were carried out using the methods described below.
(Formula Removed)10 ml of ethanol were added to 1.1 g (3.56 mmol) of ( ( 3-benzothiophenyl)methyl.).( 4-cyano-_2-nitrophenyl) amine followed by the addition of 2.4 g (17.8 mmol) of potassium carbonate. After replacing the reaction system with nitrogen, 220 mg of 10% palladium-carbon were added followed by replacing the reaction system with hydrogen and heating to 6 0°C.
After 4 hours and 30 minutes, an additional 220 mg of 10% palladium-carbon were added followed by replacing the reaction system with hydrogen and heating to 60°C. 5 hours and 10 minutes, after the start of the reaction, the reaction system was cooled to room temperature. The reaction solution was then filtered with Celite and concentrated under reduced pressure to obtain 0.93 g of a
liquid residue. Continuing, 0.93 g (2.63 mmol) of ((2-benzothiophenyl)methyl) ( 2-amino-4-raethylphenyl) amine were dissolved in 10 ml of ethanol and 2 ml of water followed by refluxing after adding 2.1 g (13.3 mmol) of potassium ethylxanthate. After 11 hours, 12.5 ml of 40% aqueous acetic acid solution were dropped in. After cooling to room temperature and concentrating under reduced pressure, the residue was purified by silica gel column chromatography (hexane:acetone = 2:1) to obtain 4 91.7 mg of l-((2-benzothiophenyl)methyl)-6-cyanobenzimidazole-2-thiol (yield of the two steps: 43%). Confirmation of compound no. 244 was carried out by identifying from the molecular weight using 1H-NMR and LC-MS.
Calculated value M = 407.08, Measured value (M+H)+ = 408.2
"H-NMR (400 MHz, CDC13) (ppm): 7.94 (s,lH), 7.76 (dd,lH), 7.52 (dd,lH), 7.42 (m,3H), 7.31 (d,lH), 7.00 (S,1H), 5.56 (s,2H), 3.35 (t,2H), 2.47 (t,2H), 2.15 (p,2H)
[Example 6]
The following target compounds were obtained using the same method as Example 5.
Production of Compound No. 34 0
4-methyl~2-nitrotrifluoroacetoanilide was used as the reagent corresponding to Step 1.
Confirmation of compound no. 340 was carried out by identifying from the molecular weight using LC-MS.
Calculated value M = 396.10, Measured value (M+H)+ = 397.0
Production of Compound No. 43 6
5-methyl-2-nitrotrifluoroacetoanilide was used as the reagent corresponding to Step 1.
Confirmation of compound no. 436 was carried out by identifying from the molecular weight using LC-MS.
Calculated value M = 396.10, Measured value (M+H)* = 3 9 7.0
[Example 7]
Production of Compound No. 3 4
Step 1
Production of ((l-methylindole-3-yl)methyl)(2-
aminophenvl)amine
(Formula Removed)
829 mg (6 mmol) of 2-nitroaniline and 1242 mg (7.8 mmol) of 1-methylindole carboxyaldehyde were dissolved in 2 0 ml of tetrahydrofuran followed by the sequential addition of 200 \il of acetic acid and 5087 mg (24 mmol} of NaBH(OAc)3 and stirring overnight at room temperature. After adding saturated aqueous sodium bicarbonate solution, extracting with ethyl acetate and drying with anhydrous magnesium sulfate, the solvent was distilled off and the residue was purified by silica gel column chromatography (hexane:ethyl acetate = 95:5) to obtain 264 mg of ((l-methylindole-3-yl)methyl)(2-nitrophenyl)amine (yield: 18%). 264 mg (0.939 mmol) of ((l-methylindole-3-yl)methyl)(2-nitrophenyl)amine were then dissolved in 10 ml of ethanol followed by the addition of 50 mg (0.047 mmol) of.10% Pd-C and stirring for 6 hours at.room temperature in a hydrogen .atmosphere. After completion of the reaction, the Pd-C was filtered out and the solvent was distilled off under reduced pressure to obtain 212 mg of ((l-methylindole-3-yl)methyl)(2-aminophenyl)amine (yield: 90%).
Step 2
Production of 1-((l-methylindole-3-
yl)methyl)benzimidazole-2-thiol
(Formula Removed)
212 mg (0.845 mmol) of ((l-methylindole-3-
l)methyl)(2-aminophenyl)amine were dissolved in 1 ml of pyridine followed by the addition of 1 ml (16.9 mmol) of carbon disulfide and refluxing for 1 hour in a nitrogen atmosphere. The solvent was distilled off followed by purification by silica gel column chromatography (hexane:ethyl acetate = 2:1) to obtain 9 6 mg of 1-((1-methylindole-3-yl)methyl)benzimidazole-2-thiol (yield: 39%) .
Step 3
Production of 4-(1-((l-methylindole-3-
yl^methyl)benzimidazole-2-ylthio)butanoic acid
(Formula Removed)
12 mg (0.342 mmol) of sodium hydride and 2 ml of tetrahydrofuran were added to a pre-dried reaction vessel. 50 mg (0.171 mmol) of 1-((l-methylindole-3-yl)methyl)benzimidazole-2-thiol and 34 ul (0.23 mmol) of 4-bromobutanoate ethyl ester were then added to the reaction vessel followed by stirring for 40 minutes at 6 0°C. Water was then added followed by extraction with ethyl acetate. After drying the ethyl acetate phase with anhydrous magnesium sulfate, the reaction solution was concentrated under reduced pressure and the resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate =3:1) to obtain 4-(l-((l-methylindole-3-yl)methyl)(benzimidazole-2-ylthio)butanoate ethyl ester. Continuing, 0.25 ml of 4 M aqueous lithium hydroxide solution were added to 1 ml of tetrahydrofuran containing this 4-(1-((l-methylindole-3-yl)methyl)(benzimidazole-2-ylthio)butanoate ethyl ester and 0.5 ml of methanol. After stirring overnight at room temperature, 6 M hydrochloric acid was added to stop the reaction followed by extraction with ethyl acetate. After washing the ethyl acetate phase with saturated brine, it was dried with anhydrous magnesium sulfate.
The solvent was then distilled off under reduced pressure to obtain 16 mg (0.042 mmol) of the target compound (yield: 25%)..
Confirmation of the compound was carried out by identifying from the molecular weight using LC-MS.
Calculated value M = 379.14, Measured value (M+H) + = 380.2
[Example 8]
Production of Compound No. 7 43
Step 1
Production of 5-(benzimidazole-2-yl)pentanoate ethyl
ester
(Formula Removed)696 jxl (5.0 mmol) of triethylamine and 893 mg (5.0 mmol) of methyladipochloride were dropped into 10 ml of a chloroform solution containing 540 mg (5.0 mmol) of orthophenylenediamine followed by stirring for 12 hours at room temperature. 2 0 ml of ethanol and 4 ml of concentrated hydirochloric acid were then added followed by stirring for 10 hours while heating and refluxing. The reaction solution was then neutralized using 5 M aqueous sodium hydroxide solution followed by extraction with ethyl .acetate.. After washing with water and concentrating under reduced pressure, the residue was purified by silica gel column chromatography (ethyl acetate only) to obtain 359 mg of 5-(benzimidazole-2-yi)pentanoate ethyl ester (yield: 30%).
Step 2
Production of 5-(1-((1,4-dimethylindole-3-
yllmethyllbenzimidazole-2-yl)pentanoic acid
(Formula Removed)42 mg (0.3 mmol) of potassium carbonate and 103 mg (0.3 mmol) of ((1,4-dimethylindole-3-
yl)methyl)trimethylammonium iodide were added to 2 ml of DMF solution containing 50 mg (0.2 mmol) of the resulting 5-(benzimidazole-2-yl)pentanoate ethyl ester followed by stirring for 2 hours at 120°C. The resulting solution was extracted with dichloromethane, washed with water and concentrated followed by purification of the residue by column chromatography (hexane:ethyl acetate =1:2). 5 ml of ethanol and 0.5 ml of 4 M aqueous sodium hydroxide solution were then added to this followed by stirring for 10 hours at 50°C and then the addition of 6 M hydrochloric acid to stop the reaction. The solution was extracted with chloroform, and after washing with water and concentrating under reduced pressure, the residue was purified by silica gel column chromatography (chloroform:methanol = 10:1) to obtain 35 mg of the target compound (yield of the two steps: 47%). Confirmation of the compound was carried out by identifying from the molecular weight using LC-MS.
Calculated value M = 375.19, Measured value (M+H)+ = 376.5
[Example 9]
Production of Sodium Salt of Compound No. 519
11.9 ml (1.19 mmol) of 0.1 M aqueous sodium hydroxide solution were added to 100 ml of an aqueous solution containing 503 mg (1.19 mmol) of the above compound no. 519 followed by stirring at room
temperature. Subsequently, the reaction solution was freeze-dried to obtain 470 mg (1.05 mmol) of the sodium salt (yield: 89%).
'H-NMR (400 MHz, DMSO-d6) (ppm): 7.37 (S,1H), 7.19 (d,lH,J=8.24 Hz),r 7.09-7.01 (m,2H), 6.80 (d,lH,J=7.09 Hz), 6.32 (S,1H), 5.66 (s,2H), 3.59 (s,3H), 3.26 (m,2H), 2.66 (s,3H), 2.27 (s,3H), 2.21 (S,3H), 1.95 (m,2H), 1.81 (m,2H)
[Example 10]
The compounds indicated below were synthesized using the respective corresponding substrates according to the same method as Example 9.
Sodium Salt of Compound No. 3 9
XH-NMR (270 MHz, DMSO-d6) (ppm): 7.57 (d,lH,J= Hz), 7.28 (d,lH,J=7 Hz), 7.20 (d,lH,J=8 Hz), 7.15-7.00 (m,3H), 6.77 (d,lH,J=7 Hz), 6.47 (s,lH), 5.69 (s,2H), 3.60 (s,3H), 3.31 (t,2H,J=7 Hz), 2.61 (s,3H), 1.99 (t,2H,J=7 Hz) , 1.84 (p,2H,J=7 Hz)
Sodium Salt of Compound No. 52
1H-NMR (400 MHz, DMSO-d6) (ppm): 7.97 (d,lH), 7.91 (d,lH,J=6.76 Hz), 7.57 (d,lH,J=7.75 Hz), 7.44-7.38 (m,3H), 7.30 (S,1H), 7.12 (m,2H), 5.63 (s,2H), 3.33 (m,2H), 2.03 (m,2H), 1.87 (m,2H)
Sodium Salt of Compound No. 135
XH-NMR (400 MHz, DMSO-d6) (ppm): 7.21-7.00 (m,4H), 6.79 (d,lH,J=7.29 Hz), 6.67 (dd,1H,J=2.43, 8.91 Hz), 6.51 (S,1H), 5.65 (S,2H), 3.75 (S,3H), 3.62 (s,3H), 3.31 (m,2H), 2.59 (s,3H), 1.95 (m,2H), 1.82 (m,2H)
Sodium Salt of Compound No. 532
"H-NMR (400 MHz, DMSO-d6) (ppm): 7.98 (d,lH,J=7.42 Hz), 7.90 (d,lH,J=6.43 Hz), 7.44-7.39 (m,2H), 7.35 (s,lH), 7.18 (m,2H), 5.57 (s,2H), 3.28 (m,2H), 2.26 (s,3H), 2.23 (s,3H), 1.99 (m,2H), 1.84 (m,2H)
[Example 10]
Production of 4-(1-((4-methylbenzothiophene-3-
yl)methyl) -5-methoxybenzimidazole-2-ylthio) butanoate
ethyl ester and 4-(1-((4-methylbenzothiophene-3-
yl)methyl)-6-methoxybenzimidazole-2-ylthio)butanoate
ethyl ester
(Formula Removed)-2-ylthio)butanoate ethyl ester were suspended in 4 ml of toluene followed by the addition of 616 u.1 (3.60 mmol) of diisopropylethylamine and 384 mg (1.59 mmol) of 4-methyl-3-(bromomethyl)benzo[b]thiophene and heating at 100°C. After allowing to react overnight, saturated sodium bicarbonate solution was added followed by extraction with ethyl acetate. The organic phase was washed with water followed by drying with magnesium sulfate and concentrating the solvent under reduced pressure. The resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate = 4:1) to obtain 114 mg of 4-(l-((4-methylbenzothiophene-3-yl)methyl)-5-methoxybenzimidazole-2-ylthio)butanoate ethyl ester (yield: 17%) and 68 mg of 4-(1-((4-methylbenzothiophene-3-yl)methyl)-6-methoxybenzimidazole-2-ylthio)butanoate ethyl ester (yield: 10%).
4-(1-((4-methylbenzothiophene-3-yl)methyl)-5-methoxybenzimidazole-2-ylthio)butanoate ethyl ester 'H-NMR (270 MHz, CDC13) (ppm): 7.71 (d,1H,J=7.56 Hz), 7.62 (d,lH,J=8.64 Hz), 7.30-7.18 (m,2H), 6.87 (dd,lH,J=2.43, 8.64 Hz), 6.61 (d,lH,J=2.43 Hz), 6.42 (S,1H), 5.74 (S,2H), 4.10 (q,2H,J=7.29 Hz), 3.75 (s,3H), 3.38 (t,2H,J=7.29 Hz), 2.89 (s,3H), 2.45 (t,2H,J=7.29 Hz), 2.11 (m,2H), 1.23 (t,3H,J=7.29 Hz)
4-(1-((4-methvIbenzothiophene-3-Yl^methyl)-6-
methoxybenzimidazole-2-vlthio)butanoate ethyl ester
XH-NMR (270 MHz, CDC13) (ppm): 7.7 0 (d,1H,J=8.10 Hz), 7.29-7.17 (m,3H), 7.02 (d,1H,J=8.91 Hz), 6.80 (dd,lH,J=2.43, 8.91 Hz), 6.40 (s,lH), 5.74 (s,2H), 4.11 (q,2H,J=7.29 Hz), 3.87 (s,3H), 3.42 (t,2H,J=7.02 Hz), 2.88 (S,3H), 2.46 (t,2H,J=7.29 Hz), 2.10 (m,2H), 1.23 (t,3H,J=7.29 Hz)
[Example 11]
The following compounds were obtained according to the same method as Example 10.
4-(1-((5-methylbenzothiophene-3-yl)methyl)-5-
irtethoxybenzimidazole-2-ylthio)butanoate ethyl ester
(Yield: 24%)
XH-NMR (270 MHz, CDC13) (ppm): 7.76 (d,lH,J=8.10 Hz), 7.62 (S,1H), 7.58 (d,lH,J=8.64 Hz), 7.25 (1H), 6.84 (dd,1H,J=2.43, 8.91 Hz), 6.81 (s,lH), 6.65 (d,lH,J=2.16 Hz), 5.47 (S,2H), 4.11 (q,2H,J=7.02 Hz), 3.74 (s,3H), 3.39 (t,2H,J=7.02 Hz), 2.51 (s,3H), 2.47 (t,2H,J=7.56 Hz), 2.11 (m,2H), 1.24 (t,3H,J=7.02 Hz)
4-(l-((5-methylbenzothiophene-3-yl)methyl)-6-
methoxybenzimidazole-2-ylthio)butanoate ethyl ester
(Yield: 18%)
"H-NMR (270 MHz, CDC13) (ppm): 7.75 (d,1H,J=8.10 Hz), 7.60 (S,1H), 7.26-7.22 (m,2H), 7.04 (d,1H,J=8.91 Hz), 6.83 (S,1H), 6.78 (dd,1H,J=2.43, 8.91 Hz), 5.47 (s,2H), 4.12 (q,2H,J=7.02 Hz), 3.84 (s,3H), 3.43 (t,2H,J=7.29 Hz), 2.50 (s,3H), 2.48 (t,2H,J=7.29 Hz), 2.12 (m,2H), 1.24 (t,3H,J=7.02 Hz)
[Example 12]
Production of 4-(1-((4-methvlbenzothiophene-3-
yl)methyl)-5-methoxvbenzimidazole-2-ylthio)butanoic
acid (Compound No. 154
84.7 mg (0.186 mmol) of the 4-(l-((4-methylbenzothiophene- 3-yl)methyl)-5-methoxybenzimidazole-2-ylthio)butanoate ethyl ester obtained in Example 10 were dissolved in a mixed solvent of 1 ml of THF and 1 ml of ethanol followed by the addition of 1 ml of 1 M aqueous sodium hydroxide solution and stirring for 1 hour at 40°C. Following completion of the reaction, 1.5 ml of 1 M hydrochloric acid were added followed by stirring for 3 0 minutes at room temperature. The resulting precipitate was filtered, washed with water, washed with ethanol and then dried to obtain 54.9 mg of the target compound (yield: 69%).
LC-MS:
Calculated value M = 426.11, Measured value (M+H)+ = 427.2
^-NMR (270 MHz, DMS0-d6) (ppm): 7.80 (d,lH,J=7.29 Hz), 7.60 (d,lH,J=8.91 Hz), 7.31-7.20 (m,3H), 6.95 (dd,lH,J=2.16, 8.91 Hz), 6.53 (s,lH), 5.94 (s,2H), 3.73 (s,3H), 3.37 (t,2H,J=7.29 Hz), 2.86 (s,3H), 2.34 (t,2H,J=7.29 Hz), 1.90 (m,2H)
[Example 13]
The following compounds were synthesized according to the.same method as Example 12.
4-(1-((4-methylbenzothiophene-3-yl)methyl)-6-
methoxybenzimidazole-2-ylthio)butanoic acid
(Compound No. 1114)
Yield: 60%
LC-MS:
Calculated value M = 426.11, Measured value (M+H)+ = 427.2
'H-NMR (2 70 MHz, DMS0-d6) (ppm): 7.7 8 (d,lH,J=7.8 3 Hz), 7.52 (d,lH,J=8.91 Hz), 7.34-7.17 (m,3H), 6.77 (dd,lH,J=2.34, 8.91 Hz), 6.37 (s,lH), 5.83 (s,2H), 3.78
(s,3H), 3.32 (t,2H,J=7.29 Hz), 2.82 (s,3H), 2.34 (t,2H,J=7.56 Hz), 1.93 (m,2H)
In this case however, 1 M hydrochloric acid was added following completion of the reaction followed by extraction with chloroform and washing with water. Drying was then performed with magnesium sulfate followed by concentrating the solvent under reduced pressure and drying to obtain the target compound.
4-(l-((5-methylbenzothiophene-3-yl)methvl)-5-
methoxybenzimidazole-2-vlthio)butanoic acid
(Compound No. 152)
Yield: 63%
LC-MS:
Calculated value M = 426.11, Measured value (M+H)+ = 426.8
XH-NMR (270 MHz, DMSO-d6) (ppm): 7.88 (d,lH,J=8.64 Hz), 7.76 (S,1H), 7.58 (d,lH,J=8.64 Hz), 7.28-7.24 (m,3H), 6.94 (dd,1H,J=2.16, 8.64 Hz), 5.72 (s,2H), 3.74 (s,3H), 3.40 (t,2H,J=7.29 Hz), 2.42 (s,3H), 2.36 (t,2H,J=7.29 Hz), 1.92 (m,2H)
4-(l-((5-methylbenzothiophene-3-yl)methyl)-6-
methoxybenzimidazole-2-ylthio)butanoic acid
(Compound No. 1112)
Yield: 79%
LC-MS:
Calculated value M = 426.11, Measured value (M+H)+ = 4 2 7.0
^-NMR (2 70 MHz, DMSO-d6) (ppm): 7.87 (d/lH,J=8.10 Hz), 7.71 (S,1H), 7.47 (d,lH,J=8.91 Hz), 7.24 (m,2H), 7.17 (d,lH,J=2.16 Hz), 6.84 (dd,lH), 5.64 (s,2H), 3.77 (s,3H), 3.38 (t,2H,J=7.02 Hz), 2.41 (s,3H), 2.37 (t,2H,J=7.56 Hz), 1.95 (m,2H)
[Example 14]
Production of HCl Salt of Compound No. 532
(Formula Removed)1.5 ml of 4 M hydrochloric acid/dioxane solution were added to 50 mg (0.122 mmol) of compound no. 532 followed by stirring at 100°C. Following completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain 53 mg (1.05 mmol) of the target compound (yield: 97%).
XH-NMR (270 MHz, DMSO-d6) (ppm): 8.00 (m,lH), 7.89 (m,lH), 7.52 (m,2H), 7.45-7.42 (m,2H), 7.32 (s,lH), 5.78 (s,2H), 3.48 (t,2H,J=7.42 Hz), 2.37 (m,2H), 2.34 (s,3H), 2.30 (s,3H), 1.92 (t,2H,J=7.09 Hz) [Example 15]
Production of HCl Salt of Compound No. 56 The target compound was obtained according to the same method as Example 14.
^-NMR (270 MHz, DMSO-d6) (ppm): 7.87 (d,lH,J=8.08 Hz), 7.74 (s,lH), 7.66 (d,lH,J=6.76 Hz), 7.58 (d,lH,J=8.74 Hz), 7.26 (m,4H), 5.70 (S,2H), 3.45 (t,2H,J=7.26 Hz), 2.42 (s,3H), 2.39 (t,2H,J=7.26 Hz), 1.98 (m,2H)
[Example 16]
Preparation of Recombinant Human Mast Cell Chymase Recombinant human mast cell chymase was prepared in accordance with the report of Urata, et al. (Journal of Biological Chemistry, Vol. 266, p. 17173 (1991)). Namely, human mast cell chymase was purified by heparin sepharose (Pharmacia) from a culture supernatant of insect cells (Th5) infected with recombinant baculovirus containing cDNA coding for human mast cell chymase. Moreover, after activating in accordance with the report of Murakami, et al. (Journal of Biological Chemistry, Vol. 270, p. 2218 (1995)), the human mast cell chymase was purified with heparin sepharose to obtain active human mast cell chymase.
[Example 17]
Measurement of Inhibition of Enzyme Activity of Recombinant Human Mast Cell Chymase After adding 2 pil of DMSO solution containing a compound of the present invention to 5 0 pil of Buffer A (0.5-3.0 M NaCl, 50 mM Tris-HCl, pH 8.0) containing 1-5 ng of the active human mast cell chymase obtained in Example 16, 50 ul of Buffer A containing 0.5 mM succinyl-alanyl-histidyl-prolyl-phenylalanylparanitroanilide (Bacchem) as substrate were added and allowed to react for 5 minutes at room temperature. The changes over time in absorbance at 4 05 nm were measured to investigate inhibitory activity.
As a result, compound nos. 39, 56, 58, 59, 63, 148, 154, 519, 532, 534, 536, 538, 615, 1112 and 1114 were observed to demonstrate inhibitory activity of IC50 = 1 nM to less than 10 nM, while compound nos. 34, 38, 41, 42, 52, 54, 135, 137, 152, 244, 340, 436, 514, 521 and 628 were observed to demonstrate inhibitory activity of IC50 = 10 nM to 100 nM.
As has been shown above, the benzimidazole derivatives of the present invention exhibit potent chymase inhibitory activity. Thus, the benzimidazole derivatives of the present invention were clearly demonstrated to be human chymase activity inhibitors that can be applied clinically for use in the prevention and/or treatment of various diseases involving human chymase.
[Example 18] Production of Tablets
Tablets were produced having the individual tablet composition shown below.
Compound No. 3 9 50 mg
Lactose 230 mg
Potato starch 80 mg
Polyvinylpyrrolidone 11 mg
Magnesium stearate 5 mg
The compound of the present invention (compound of the examples), lactose and potato starch were mixed followed by uniformly wetting with a 20% ethanol solution of polyvinylpyrrolidone, passing through a 20 mesh sieve, drying at 45°C and again passing through a 15 mesh sieve. The granules obtained in this manner were then mixed with magnesium stearate and compressed into tablets.
[Example 19]
Measurement of Blood Concentration During
Administration by Intragastric Forced Feeding'to
Rats
The compounds indicated with the above compound nos. 39, 52 and 244 were administered by intragastric forced feeding to male SD rats while fasting at a dose of 30 mg/kg, after which blood samples were collected immediately after administration and at 30 minutes and 1, 2 and 4 hours after administration. Following collection of blood samples, where samples were immediately separated into serum components, the compound of the present invention was extracted by ordinary solid phase extraction methods, and the resulting samples were analyzed by HPLC using an ODS column (32% acetonitrile-water-0.05% TFA was used for the mobile phase for compound nos. 52 and 244, while 47% acetonitrile-water-10 mM ammonium acetate buffer (pH 4.0) was used for the mobile phase for compound no. 39) followed by measurement of the amount of the unchanged form. Those results are shown in the table below.
(Table Removed)On the basis of the above results, the compounds of the present invention were rapidly absorbed after administration, and blood concentrations of the unchanged form shown in the table-were measured after 30 minutes.
Moreover, although blood concentrations decreased gradually until 4 hours after administration, a considerable amount of the unchanged forms could still be confirmed even at. 4 hours after administration. Thus, the compounds of the present invention were determined to be a group of compounds having superior pharmacokinetic properties. The pharmacokinetic properties of the group of compounds in which A is -CH2CH2CH2- are particularly superior.
[Example 20]
In Vitro Metabolism Test Using Liver Microsomes (Ms)
Measurement Method: * Reaction Solution Composition and Reaction Conditions
(Table Removed)* MR Calculation Method
The metabolic rate was determined from the decrease in the amount of the unchanged form at each reaction time and the reaction time based on assigning a value of 100% to the amount of the unchanged form at the initial concentration (reaction time: 0 minutes), and the metabolic rate at the time the metabolic rate reached a maximum was evaluated as the MR value.
MR = (substrate concentration at reaction time: 0 min. substrate concentration after reaction) reaction time -r protein concentration (nmol/min./mg protein) These methods were used to obtain the measurement
results indicated below.
(Table Removed)According to the above results, the compounds of the present invention are a group of metabolically stable compounds. The group of compounds in which A is -CH2CH2CH2- was determined to be a group of particularly metabolically stable compounds.
Industrial Applicability
The benzimidazole derivatives of the present invention or their medically allowed salts exhibit potent human chymase inhibitory activity. Thus, said
benzimidazole derivatives or their medically allowed salts can be used as preventive and/or therapeutic agents that can be applied clinically as human chymase inhibitors for inflammatory diseases, allergic diseases, respiratory diseases, cardiovascular diseases or bone and cartilage metabolic diseases.
Claim
1. A benzimidazole derivative or its medically acceptable salt represented by the following formula (1)
(Formula Removed) wherein, R1 and R2 may be the same or different and each independently represents a hydrogen atom, halogen atom, cyano group, alkyl group having 1-4 carbon atoms, or alkoxy group having 1-4 carbon atoms;
A represents an unsubstituted, linear alkylene group having 2-4 carbon atoms
E represents -COOH;
G represents CFh
M represents -S-;
J represents a substituted benzothiophenyl group; the substituent that can be possessed by said benzothiophenyl group is selected from a halogen atom, a linear or branched alkyl group having 1-6 carbon atoms or a trihalomethyl group; and, one or more of these
substituents may be substituted at optional positions on the ring;
and,
X represents —CH=.
2. A benzimidazole derivative as claimed in claim 1 represented the formula:
(Formula Removed)
andits medically acceptable salt.