This invention particularly relates to novel pyridylmethylsulfinyl benzimidazole represented by the general formula (I), its tautomers, its derivatives, its analogs, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts, its pharmaceutically acceptable solvates and pharmaceutical compositions containing them.

The present invention also relates to a process for the preparation of the above said novel pyridylmethylsulfinyl benzimidazoles of the general formula (I), its tautomers, its derivatives, its analogs, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts, its pharmaceutically acceptable solvates and pharmaceutical compositions containing them.

The pyridylmethylsulfinyl benzimidazole derivatives of general formula (I) of the present invention are useful for prophylaxis and I or the treatment of the gastric and duodenal ulcers, as

cytoprotective agents for the gastrointestinal tract and as antibacterial agents, more specifically as bactericides for Helicobacter pylori. More specifically, the pyridylmethylsulfinyl benzimidazole derivatives of general formula (I) of the present invention appear to inhibit the gastric acid secretion by blocking the proton pump of H+ I K+ - ATPase, an enzyme present in the parietal cells of the stomach although there may be alternative mechanisms of action.

The present invention also relates to a process for the preparation of the above said novel pyridylmefflylsulfinyl benzimidazoles of general formula (I), its tautomers, its derivatives, its analogs, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts, its pharmaceutically acceptable solvates, and novel intermediates.

Background of the Invention Gastric and duodenal ulcers are gastro intestinal diseases caused by various factors such as mental stress, dietary habits, intake of irritable food etc. The ulcers are caused due to damage of gastric membrane because of excess secretion of gastric acid.

The therapeutic agents which have been commonly used for the treatment of ulcers are antacids for neutralizing gastric acid, antipepsin agents for protecting the gastric mucous membrane and anticholinergic agents for inhibiting gastric acid secretion. At the present time, Histamine-H2-receptor antagonists have been widely used for treating gastric and duodenal ulcers.

More recently, proton pump inhibitors are gaining importance since they block the proton pump of H+/K+-ATPase, an enzyme specifically present in the parietal cells of the stomach to inhibit the gastric acid secretion at the final stage. One of the earliest proton pump inibitors is 2- [[(4-methoxy-3 '5 dimethyl)pyridin-2-yl]methylsulfinyl] 1H-benzimidazole whose generic name is Omeprazole (see Patent Application. Nos. EP 0 005 129; JP 79,141,783 and US 4,255,431) having the following formula (II) which is being used to treat the above mentioned disease conditions.

A wide variety of compounds related to Omeprazole having a pyridylmethylsulfinyl benzimidazole structure are described in various patent documents.

A group of compounds having general formula (IIa) wherein R'represents hydrogen, methoxy or trifluoromethyl, R2 and R3 independently represent hydrogen or methyl, R4 represents fluoroalkyl and n is an integer ofO to 1 have been described in European Patent application No.

0 174 726.

An example of these compounds is Lansoprazole shown in formula (IIb).

A group of compounds having general formula (IIc) wherein R' represents (C1-C3)alkyl which is completely or predominantly substituted by fluorine or a chlorodifluoromethyl radical, R2 represents hydrogen, halo, trifluoromethyl, (C1-C3)alkyl, (C1-C3)alkoxy which is completely

or predominantly substituted by fluorine, Rl and R2 together with the oxygen atom to which R1 is bonded are (C1-C2)alkylenedioxy which is optionally or completely substituted by fluorine or chlorotrifluoroethylenedioxy, one of R3 and K5 represents (C1-C3)alkoxy and the other represents hydrogen atom or (C1-C3)alkyl, and the R4 is (C1-C3)alkoxy and n is an integer of 0 to 1 are disclosed in US Patent 4,758,579.

An example of these compounds is Pantoprazole shown in formula (IId) A group of compounds having general formula (IIe) where J, K represents hydrogen or alkyl, Rl, R2 represents hydrogen, alkyl, alkoxy, halo, haloalkyl, alkoxycarbonyl or CO2H, X represents oxygen, sulfur or NR3, where R3 represents hydrogen, alkyl, Ph, PhCH2 or alkoxycarbonyl, Z represents O(CH2)pOR4, O(CH2)qK5, O(CH2)rO(CH2)sOR6, SOtA, NR8CH2Ph, OR9, succinimidyl etc., A represents alkyl, alkoxycarbonyl, pyridyl, furyl, (CH2)wC6H4R7, 2- benzimidazolyl or 2-benzothiazolyl etc., R4 represents hydrogen, alkyl, aryl or aralkyl, K5 represents halo, alkoxycarbonyl, aryl or heteroaryl, R6 represents hydrogen or alkyl, R7 represents hydrogen, alkyl, alkoxy or halo, K8 represents alkyl or acetyl, R9 represents hydrogen, alkyl or <BR> <BR> <BR> aryl, misanintegerof2tolO, nandtisofOto2, pand qisoflto3, risoflto5andwisO to 1 are disclosed in US Patent 5045552.

An example of these compounds is Rabeprazole shown in formula (IIf).

A group of compounds having general formula (JIg) where R represents a hydrogen atom, or lower alkyl group; Rl represents a hydrogen atom, halogen atom, lower alkoxy group, lower cycloalkoxy group, amido group, substituted phenoxy group, substituted benzyloxy group, lower alkoxy group optionally containing halogen atoms, nitro group, hydroxyl group, lower alkenyloxy group, lower alkylthio group or a group -NK4K5, wherein R4, R5 may be same or different and each represent a hydrogen atom, lower alkyl group, or R4, R5 mutually combine together with the nitrogen atom adjacent thereto form a 5 - 6 membered cyclic structure ; R2 represents hydrogen, halogen, lower alkyl group, optionally containing halogen atom, lower alkoxy group, optionally containing halogen atom, hydroxyl group, acyl group, lower alkoxycarbonyl group, nitro group, or amino group; R3 represents a hydrogen, lower alkyl group, lower alkoxymethyl group, lower alkylcarbonyl group, lower alkoxycarbonyl group, carbamoyl group, lower alkylcarbamoyl group, lower alkylcarbonylmethyl group, lower alkoxycarbonylmethyl group, lower acyloxymethyl group, or lower alkylsulfonyl group; n represents 0 or 1 and A represents a methine carbon or nitrogen are disclosed in European Patent application No. 0 434 999.

An example of these compounds is Nepaprazole shown in formula (IIh).

A group of compounds having general formula (IIi) where Rl represents a straight chain or branched (C1-C8)alkoxy which may be substituted with cycloalkyl or (C2-C4)fluoroalkoxy, R2 represents hydrogen, methyl or methoxy, R3 and R4 represent hydrogen or methyl and may be the same or different are disclosed in European Patent application No. 0 254 588.

An example of these compounds is shown in formula (IIj) A group of compounds having general formula (IIk) where R1 to R4 represents hydrogen, (C1-C6)alkyl, (C1 - C6)alkoxy, C1- C6)alkanoyl, (C1- C6)alkoxycarbonyl, halo, fluoroalkyl, fluoroalkoxy, or R2 and R3 together form a group -O(CR2)mO-, R is hydrogen or fluorine, m is 1 or 2, R5 and R6 represents hydrogen, (C, - alkyl, or (C3 - C6)cyclosalkyl, R5 and R6 together with the nitrogen atom to which they are attached form an azetidinom, pyrrolidino, piperazino, N-(C1-C4)alkylpiperazino, piperidino, or morpholino group, and one of R7 and R8 is fluorine and the other is hydrogen, fluorine, or (C, - C6)alkyl and n is an integer of 0 to 2 are disclosed in European Patent application No. 0 246 774.

An example of this class of compounds is shown in formula (II 1)

A group of compounds having general formula (IIm) where R represents hydrogen or alkanoyl group and n is an integer ranging from 0 to 2, are disclosed in the Japanese Patent application No. 62,108,879.

An example of this class of compounds is shown in formula (IIn) A group of compounds having general formula (IIo) where A denotes -CH=CH- or S and, R', R3 and R4 represents independently of one another, denote hydrogen, or lower alkyl group, R2 represents hydrogen or lower alkoxy group and n is an integer ranging from 0 to 1 are disclosed in US Patent 4,818,760.

An example of this class of compounds is shown in formula (IIp).

A group of compounds having general formula (IIq) where X represents S, SO or SO2; Y represents halogen; R1 and R2 are independently hydrogen, or alkyl group; R3 represents hydrogen, (C, - alkyl, SR6, N(R7)2, 1-piperidinyl, 4-morpholinyl, -methylpiperazin-1-yl, 1- pyrrolidinyl, or a group of formula OR6 or -O(CH2)m-Z, wherein R6 represent (C, - C4)alkyl, (C2 - C4)alkenyl, optionally substituted (C3 - C10)cyclosalkyl, (C2 - C5)floroalkyl or phenyl or benzyl, each of which is independently substituted with one or more halogen or (C, - alkyl or alkoxy optionally substituted with halogen, R7 is hydrogen or (C1 - C5)alkyl, Z represents a group of formula O(CH2)pOR8, O(CH2)qR9 or O(CH2)rO(CH2)sOR10 wherein p and q are independently an integer 1 to 3, r and s are independenetly an integer 1 to 5, R8 represents hydrogen, lower alkyl, aryl or aralkyl, R9 is hydrogen, alkoxycarbonyl, aryl or heteroaryl and R10 is hydrogen or lower alkyl, m is an integer of 2 to 10; and R4 and R5 independently from each other represent hydrogen or (C, - alkyl or R4 and R3 together with the carbon atoms adjacent to the pyridine ring form

a ring, R3 and K5 or R4 and R3 together represent -CH=CH-CH=CH-, O (CH2) n, O(CH2)nO, CH2(CH2)n or OCH=CH-, wherein n represents an integer of 1 to 4 are disclosed in Patent application No. GB 2 295 614.

An example of this class of compounds is shown in formula (IIr) Summarv of the Invention The above mentioned compounds are highly effective for the treatment of gastrointestinal disorders. But it has been suggested that because of their longer duration of action or in other words the irreversible binding to the H+ I K+ -ATPase enzyme may lead to potentially serious side effects for example gastric carcinoids (Ref: Scand. J. Gastroenterol., 1985, 20, 53).

Therefore, we focussed our research effort for developing novel compounds for prophylaxis and I or the treatment of ulcers, as cytoprotective agents for gastrointestinal tract and

as antibacterial agents, more specifically as bactericides for Helicobacter pylori, for inhibiting gastric acid secretion, which may have shorter duration of action.

The main objective of the present invention is therefore, to provide novel pyridylmethylsulfinyl benzimidazoles of the general formula (I), its derivatives, its analogs, its tautomers, its various isomers, its polymorphs, its pharmaceutically acceptable salts, pharmaceutically acceptable solvates and pharmaceutical compositions containing them.

Another objective of the present invention is to provide novel pyridylmethylsulfinyl benzimidazoles of the general formula (I), its derivatives, its analogs, its various isomers, its polymorphs, its pharmaceutically acceptable salts, its pharmaceutically acceptable solvates and pharmaceutical compositions containing them having a better safety profile and shorter 11+ I Kt -ATPase enzyme inhibition time.

Yet another objective of the present invention is therefore, to provide a process for the preparation of novel pyridylmethylsulfinyl benzimidazoles of the general formula (I), its derivatives, its analogs, its tautomers, its various isomers, its polymorphs, its pharmaceutically acceptable salts, pharmaceutically acceptable solvates and pharmaceutical compositions containing them.

Still another objective of the present invention is to provide a novel intermediate of formula (IV) where X and Y may be same or different and independently represent a hydrogen, halogen, optionally halogenated (C, -C6)alkoxy group, or optionally halogenated(C, -C6)alkyl group ;A represents a substituted or unsubstituted, 3 to 7 membered nitrogen containing heterocycle

excluding substituted or unsubstituted pyrroles; A may further contain one or more heteroatoms selected from N, O, S or a group NR5 where R5 represents hydrogen, (C,-C6) alkyl, aralkyl, acyl, alkoxycarbonyl, aryloxycarbonyl, or aralkoxycarbonyl groups; the heterocycle A, is linked specifically through N- atom to the benzimidazole moiety; the group A may be saturated or may contain one or more double bonds.

Detailed description of the invention Pyridylmethylsulfinyl benzimidazoles of the present invention have the general formula (I) In the above formula (I), X and Y may be same or different and independently represent a hydrogen, halogen, optionally halogenated (C,-C6)alkoxy group, or optionally halogenated(C,-C6)alkyl group; A represents a substituted or unsubstituted, 3 to 7 membered nitrogen containing heterocycle excluding substituted or unsubstituted pyrroles; A may further contain one or more heteroatoms selected from N, O, S or a group NR5 where K5 represents hydrogen, (C,-C6) alkyl, aralkyl, acyl, alkoxycarbonyl, aryloxycarbonyl, or aralkoxycarbonyl groups; the heterocycle A, is linked specifically through N- atom to the benzimidazole moiety; the group A may be saturated or may contain one or more double bonds; R4 represents hydrogen, halogen or (C,-

C3) alkyl group ; R2 and R3 may be same or different and independently represent hydrogen, halogen, nitro, cyano, optionally substituted groups selected from amino, (C,-C6)alkyl, (C,- C6) alkoxy, aryloxy or aralkoxy groups; R1 represents hydrogen, halogen, substituted or unsubstituted groups selected from (C1-C8)alkyl, aryl, aralkyl, (C3-C, 0)cycloalkyl, (C, - C6) alkylthio, (C, -C6)alkenylthio, heterocyclyl, amino, (C1-C8)alkylamino, dialkylamino, arylamino, diarylamino, alkylarylamino, (C, -C6)alkoxy, (C2-C6)acyloxy, (C3-C10)cycloalkyloxy, aralkoxy, aryloxy, alkoxyalkoxy, or a group -O-(CH2)m-O-(CH2)p-R6 where m is an integer ranging from 1 to 10 and p is an integer ranging from 0 to 3 and R6 is a linear or branched (C,- C6) alkyl, heterocyclyl, heteroaryl, aralkyl, hydroxy, alkoxy, aryloxy, aralkoxy, alkoxycarbonyl, alkoxyalkyl, or alkoxyalkoxy groups ; and n is an integer ranging from 0 to 2.

Suitable heterocycles represented by A includes substituted or unsubstituted aziridinyl, azetidinyl, azepinyl, piperidinyl, pyrrolidinyl, pyrrolinyl, hexahydroazepinyl, 3-oxazepinyl, 4- oxazepinyl, 3-thiazepinyl, 4-thiazepinyl, 1,3-diazepinyl, 1,4-diazepinyl, piperazinyl, 1,3- diazolidinyl, morpholinyl, 4-thiomorpholinyl, oxazolidinyl, imidazolyl, triazolyl, pyrazolyl, 2- pyrazolinyl, 1 ,4-dihydropyridazinyl, 4-oxazolinyl, 4-thiazolinyl, 1 4-oxazinyl, tetrahydropyridinyl, and the like.

The heterocycle A may be substituted and suitable substituents on the heterocycle represented by A may be selected from the group comprising halogen, amino, hydroxy, cyano, oxo, formyl, hydroxylamino, hydroxylimino, (C1-C6)alkyoxyamino, (C1-C6)alkyoxyimino, (C,- C6) alkyl, (C3-C, 0)cycloalkyl, hydroxy(C, -C6)alkyl, mercapto, thio(C1-C6)alkyl, (C1-C6)alkylthio, amino(C, -C6)alkyl, (C, -C6)alkylamino, dialkylamino, arylamino, (C, - C6)alkoxy, aryloxy, (C3- C, 0)cycloalkyloxy, (C, -C3)alkylenedioxy, aryl, heterocyclyl, N-alkylimino, alkoxyalkyl, acyl, acyloxy, alkoxycarbonyl, or aryloxycarbonyl groups. These substituents may further be substituted and are selected from the group consisting of (C,-C3)alkyl, aryl, (C,-C3)alkoxy, aryloxy, hydroxy, halogen, amino(C , -C3)alkyl, and hydroxy(C, -C3)alkyl groups.

Preferred substituents on the heterocycle A include halogen atom, hydroxy, (C,-C6)alkyl, (C-C6) alkoxy, hydroxy(C1-C6)alkyl, amino, hydroxylamino, hydroxylimino, aryl, cyano, oxo, or (C,-C3)alkylenedioxy groups.

The groups Rl, R2 and R3 may be substituted and may be selected from halogen, (C,- C3)alkyl, aryl, aralkyl, (C,-C3)alkoxy, hydroxy, amino, amino(C,-C3)alkyl, and hydroxy(C1- C3) alkyl groups.

The alkyl moiety defined in this specification with respect to alkyl, alkylamino, dialkylamino, alkylarylamino, alkylthio, alkylimino and the like may be linear or branched.

Examples include methyl, ethyl, n-propyl, isopropyl, l-methylpropyl, tert.-butyl, n-pentyl, 1- ethylpropyl, isoamyl, n-hexyl groups and the like.

The alkoxy group and alkoxy moiety of alkoxyalkyl, alkoxycarbonyl, alkoxyamino, alkoxyalkoxy group defined in this specification may be linear or branched and are derived from the above mentioned alkyl groups.

The halogen atom defined in this specification includes chlorine, bromine, fluorine and iodine.

Examples of acyl group may be acetyl, propionyl, butyryl, benzoyl and the like, which may be optionally halogenated.

Examples of acyloxy group are derived from the above mentioned acyl groups.

Examples of aryl group may be phenyl, naphthyl and the like, which may be optionally halogenated.

Examples of the group aralkyl and aralkyl moiety in aralkoxycarbonyl include benzyl, phenethyl, phenyl(C3-C6)alkyl groups and the like which may be optionally halogenated.

Examples of the group heterocyclyl include thienyl, furyl, pyrrolyl, oxazolyl, isoxazolyl, imidazolyl, thiazolyl, isothiazolyl, pyrimidinyl, pyridyl, pyridazinyl, indolyl, aziridinyl, pyrrolidinyl, piperidinyl, morpholinyl, thiomorpholinyl, pyrazinyl, benzoxazinyl, benzothiazinyl and the like.

Preferred groups represented by X and Y include hydrogen, halogen especially chlorine and fluorine, optionally halogenated (C,-C6)alkoxy, especially optionally fluorinated (C,- C3) alkoxy, optionally halogenated (C,-C6)alkyl, especially optionally fluorinated (C,-C3)alkyl group.

Preferred group represented by R4 is hydrogen atom.

Preferred groups represented by R2 and R3 include hydrogen, halogen, optionally halogenated (C,-C3)alkyl, especially halogen being fluorine, optionally halogenated (C,- C3) alkoxy groups, especially halogen being fluorine.

Preferred groups represented by Rl include hydrogen, halogen, optionally halogenated (C,- C6) alkyl, optionally halogenated (C,-C6)alkoxy, amino, optionally halogenated alkylamino, optionally halogenated dialkylamino, heterocyclyl such as pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, azepinyl and the like, optionally halogenated alkoxyalkoxy or a group -O-(CH,),- O (CH2) p-R6 as defined above.

The use of term halogenated means that the group is substituted with one or more halogen atoms.

The use of term fluorinated means that the group is substituted with one or more fluorine atoms.

Pharmaceutically acceptable salts forming part of this invention include acid addition salts such as hydrochloride, hydrobromide, nitrate, phosphate, perchlorate, sulfate, acetate, maleate, tartrate, methanesulfonate, benzenesulfonate, tosylate, palmoate, succinate, salicylate, hydroxynaphthoate, ascorbate, glycerophosphate, ketoglutarate, pyruvate, benzoate, hydroxybenzoate, aminobenzoate, phenylacetate, salts of arginine, aspartic acid, glutamic acid tryptophan, methionine, and the like. Salts may also include alkali metal salts such as Li, Na, K and alkaline earth metal salts such as Ca or Mg salts.

Acid addition salts are not preferred when n represents one.

Pharmaceutically acceptable solvates may be hydrates, or comprising other solvents of crystallisation such as alcohols.

The compounds of the present invention may also be present as stereoisomers.

Particularly preferred compounds according to the present invention include compounds of formula (I) wherein X represents hydrogen or fluorine; Y represents hydrogen or fluorine; n represents an integer 1

R2 represents hydrogen, halogen, optionally alkylated amino, methyl, or methoxy group; R3 represents hydrogen, fluoro, methyl, or methoxy group; R1 represents hydrogen, methyl, methoxy, 3-methoxypropoxy, chloro, trifluoroethyl, heterocyclyl groups such as pyrrolidinyl, piperidinyl, morpholinyl, piperazinyl or azepinyl groups; The N-linked heterocycle A represents optionally substituted imidazolyl, pyrrolidinyl, piperidinyl, hexahydroazepinyl, piperazinyl or morpholinyl groups.

Particularly useful compounds according to the present invention includes 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluor o-5-(imidazol-1-yl)-1H- benzimidazole; 2-[3 -Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylthio] -6-fluoro-5 -(imidazol- 1 -yl)- 1 H- benzimidazole; 2-[[(4-Methoxy-3methyl)pyridin-2-yl]methylthio]-6-fluoro-5-( imidazol-1-yl)-1H- 2-[[(4-(3-Methyoxypropxy)-3-methyl)pyridin-2-yl]methylthio]- 6-fluoro-5-(imidazol-1-yl)-1H-2-[[(4-Methoxy-3,5- benzimidazole; 2-[[(4-Methoxy)pyridin-2-yl]methylthio]-6-fluoro-5-(imidazol -1-yl)-1H-benzimidazole; 2-[[(4-Chloro-3- -methyl)pyridin-2-yl]methylthio] -6-fluoro- 5 -(imidazol-1-yl)-1 H-benzimidazole; <BR> <BR> <BR> <BR> 2- [[(4-Methoxy- ,5-dimethyl)pyridin-2-yl]methylthio]-6-fl benzimidazole; 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-20-yl]methylth io]-6-fluoro-5-(morpholin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (imidazol-1-yl)-1H- benzimidazole; 2-[[(4-(3 -Methoxypropoxy)-3 -methyl)pyridin-2-yl}methylthio] -6-fluoro-5 -(morpholin-1-yl)-1 H- benzimidazole; 2-[[(4-Morpholin-1 -yl)-3 -methylpyridin-2-yl]methylthio] -6-fluoro-5 -(morpholin-1-yl)-1 H- benzimidazole;

2-[[(4-Piperidin-1-yl)-3-methylpyridin-2-yl]methyltho]-6-flu oro-5-(morpholin-1-yl)-1H- benzimidazole; 2-[[(4-Methylpiperazin-1-yl)-3-methylpyridin-2-yl]methylthio ]-6-fluoro-5-(imidazol-1-yl)-1H- benzimidazole; 2-[[(3-Methyl)pyridin-2-yl]methylthiop]-6-fluoro-5-(morophol in-1-yl)-1H-benzimidzole; 2-[[(4-Methoxy-3 ,5-dimethyl)pyridin-2-yljmethylthioj-6-fluoro-5-(piperidin- 1-yl)-1H- benzimidazole; 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylthi o]-6-fluoro-5-(imidazol-1-yl)-1H- benzimidazole; 2-[[(4-Methyoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5 -(imidazol-1-yl)-1H- benzimidazole; 2-[[(4-Piperidin-1-yl)-3-methylpyridin-2-yl]methylthio]-6-fl uoro-5-(imidazol-1-yl)-1H- benzimidazole; 2-[[(4-Methyoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluo ro-5-(4-methylpiperazin-1-yl)-1H- benzimidazole; 2-[[3-Methyl-4-(2,2,2-trifluoroethyoxy)pyridin-2-yl]methylth io]-6-fluoro-5-(4-methylpiperazin-1- yl)-1H-benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (4-methylpiperazin-1-yl)-1H- benzimidazole; 2-[[(3-Methyl)pyridin-2-yl]methylthio]-6-fluoro-5-(4-methylp iperazin- 1-yl)-1 H-benzimidazole; 2-[[(4-methoxy-3,5-dimethyl-pyridin-2-yl]methylthio]-6-fluor o-5-(4-t- butyloxycarbonylpiperazin-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3-0methyl)pyridin-2-yl]methylthiop]6-fluoro-5 -(4-t-butyloxycarbonylpiperazin- yl)-1H-benzimidazole; 2-[[(4-methoxy-3 -methyl)pyridin-2-yl]methylthio] -6-fluoro-5 -(4-(ethylenedioxy)piperidin- 1-yl)- 1 H-benzimidazole; 2-[[(4-methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluor-5-( 4-pipperidon-1-yl)-1H- benzimidazole);

2-[[(4-Methoxy-3 -methyl)pyridin-2-yljmethylthio] -6-fluoro-5 -(4-(hydroxyimino)piperidin- 1-yl)- 1 H-benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- [4-(hydroxy)piperidin-1-yl]-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (hexamethyleneimin-1-yl)-1H- benzimidazole; 2-[[(4-Meorpholin-1 -yl)-3 -methy1)pyndin-2-yl]melllthio] -6-fluoro-5 -(hexamethyleneimin- 1-yl)- 1H-benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (2-(methoxymethyl)pyrrolidin-1- yl)-1H-benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (pyrrolidin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3,5-dimyethyl)pyridin-2-yl]methylthio]-5-(mor pholin-1-yl)-1H-benzimidazole; 2-[[3 -Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylthiop -5-(morpholin-1 -yl)- 1 H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-5-(morpholi n-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-5-(4-me thylpiperazin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3 -methyl)pyridin-2-yl)methylthio]-5-(4-methylpiperain- 1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-5-(4-t-buty loxycarbonylpiperazin-1-yl benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-5-(piperidi n-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3 -methyl)pyridin-2-yl]methylthio] -5-(hexamethyleneimin- 1-yl)-1H- benzimidazole; 2- [[(4-Methoxy-3 -methyl)pyridin-2-yl]methylthio]-4,6-difluoro-5-(morpholin-1 -yl)-1H- benzimidazole;

2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-4,6--di fluor-5-(4-methylpiperazin-1-yl)- 1 H-benzimidazole; 2-[[(4-Methoxy-3 ,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-fluoro-5- -(imidazol-1-yl)-1 H- benzimidazole; 2-[[(4-Methoxy-3 ,5-dimethyl)pyridin-2-yl]methylsulfinyl] -6-fluoro-5-(imidazol- 1 -yl)- 1 H- benzimidazole, sodium salt; 2-[[(4-Methyox-3,5 -dimethyl)pyridin-2-yl]methylsulfonyl] -6-fluoro-5 -(imidazol-1-yl)-1 H- benzimidazole; 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridine-2-yl]methylsu lfi 1H-benzimidazole; 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridine-2-yl]methylsu lfi 1H-benzimidazole;, sodium salt; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]6-fluor- 5-(imidazol- 1 -yl)-1H- benzimidazole; 2-[[(4-(3 -Methoxypropoxy)-3 -methyl)pyridin-2-yl]methylsulfinyl]-6-fluoro-5 -(imidazol- 1 -yl)- 1 H-benzimidazole; 2-[[(4-Methoxy)pyridin-2-yl]methylsulfinyl]-6-fluoro-5-(imid azol-1-yl)-1H-benzimidazole; <BR> <BR> <BR> 2- [[(4-Methoxy)pyridin-2-yl]methylsulfinyl] -6-fluoro-5-(imidazol- H-benzimidazole, sodium salt; 2-[[(4-Chloro-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor- 5-(imdiazol- 1 -yl)- 1 H- benzimidazole; 2- [[(4-Methoxy-3 ,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-fluoro-5-(morphol in- H- benzimidazole; <BR> <BR> <BR> 2-[[(4-Methoxy-3,5 -dimethyl)pyridin-2-yl]methylsulfinyl] -6-fluoro-5-(morpho -yl)- 1 H- benzimidazole, sodium salt; 2-[[3 -Methyl-4-(2,2,2-trifloroethoxy)pyridin0-2-yl]methoylsulfiny l] -6-fluoro-5 -(morpholin- 1 -yl)- 1 H-benzimidazole;

2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsul finyl]-6-fluoro-5-(morpholin-1-yl)- 1H-benzimidazole, sodium salt; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(morpholin- 1 -yl)- 1 H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(morpholin- 1 -yl)- 1 H- benzimidazole, sodium salt; 2-[[(4-(3-Methoxypropoxy)-3-methyl)pyridin-2-yl]methylsulfin yl]-6-fluoro-5-(morp 1H-benzimidazole; 2-[[4-(Morpholin- 1 -yl)-3 -methylpyridin-2-yl]methylsulfinyl]-6-fluoro-5 -(morpholin-1-yl)-1 H- benzimidazole; 2-[[4-(Morpholin-1 -y1)-3 -methylpyridin-2-yl]methylsulfinyl]-6-fluoro-5 -(morpholin-1-yl)-1 H- benzimidazole, sodium salt; 2-[[(4-Piperidin-1 -yl)-3-methylpyridin-2-yl)methylsulfinyl benzimidazole; 2-[[(3-Methyl)pyridin-2-yl]methylsulfinyl]-6-fluoro-5-(morph olin-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-f luoro-5-(piperidin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-f luoro-5-(piperidin-1-yl)-1H- benzimidazole; sodium salt; 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsul finyl]-6-fluoro-5-(piperidin-1-yl 1-benzimidiazole; 2-[[(4-methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(piperidin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(piperidin-1-yl)-1H- benzimidazole, sodium salt; 2-[[(4-Piperidin-1 -yl)-3-methyl)pyridin-2-yl]methylsulfiny benzimidazole;

2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]Methylsulfinyl]-6-f luoro-5-(4-methyliperazin-1-yl)- 1H-benzimidazole; 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsul finyl]-6-fluoro-5-(4- methylpiperain-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-f luoro-5-(4-t butyloxycarbonypiperazin-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-f luoro-5-(4-t butyloxycarbonypiperazin-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3methyl)pyridin-2-yl]methylsulfinyl]-6-fluoro -5-(4-(ethylenedioxy)piperidin-1- yl)-1H-benzimidazole; 2-[[(4-Methoxy-3methyl)pyridin-2-yl]methylsulfinyl]-6-fluoro -5-(4-(ethylenedioxy)piperidin-1- yl)-1H-benzimidazole; sodium salt; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-[4-piperidin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-[4-piperidin-1-yl)-1H- benzimidazole; sodium salt; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-[4-(hydroxyimino)piperidin-1- yl)-III-benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(4-hydroxypiperidin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(hexamethyleneimin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(hexamethyleneimin-1-yl)-1H- benzimidazole; sodium salt; 2-[[(4-Morpholin-1-yl)3-methyl)pyridin-2-yl]Melthylsulfinyl- 6-fluoro-5-(hexamethyleneimin-1- y)-1H-benzimidazole; 2-[[(4-Methoxy-3-methyl)lpyridin-2-yl]methylsulfinyl]6-6fluo ro-5-(2-methoxymethyl)pyrrolinin- 1-yl)-1H-benzimidazole;

2-[[(4-Methoxy-3- -methyl)pyridin-2-yl]methylsulfinyl]-6-fl benzimidazole; <BR> <BR> <BR> <BR> 2-[[(4-Methoxy-3 ,5-dimethyl)pyridin-2-yl]methylsulfinyl] -5-(morpholin- 1 -yl)-1H- benzimidazole; 2-[[3 -Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsulfinyl ]-5-(morpholin 1 -yl)- 1 H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-5-(morp holin-1-yl)-1H-benzimidazole; 2-[[(4-Methoxy-3 -methyl)pyridin-2-yl]melthylsulfinyl]-5 -5-(morpholin-1-yl)-1 H-benzimidazole, sodium salt; 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-5(4 -methylpiperazin-1-yl)-1H- benzimidazole; 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-5-(4-t- butyloxycarbonylpipazin-1-yl 1H-benzimidazole; 2-[[(4-Melthoxy-3-methyl)pyridin-2-yl]methylsulfinyl]5-(hexa methyleneimin-1-yl)-1H- benzimidazole and 2- [[(4-Methoxy-3 -methyl)pyridin-2-yl]methylsulfinyl] -4,6-difluor-5-(morpholin-1-yl)-1 H- benzimidazole.

The present invention provides a process for the preparation of novel antiulcer compounds especially pyridylmethylsulfinyl benzimidazole derivatives of the general formula (I) which comprises a) reacting a compound of general formula (III) wherein Rl, R2, R3, R4 are as defined earlier in general formula (I) and L is a leaving group such as Cl, Br, I, p-toluenesulfonate, methanesulfonate, trifluoromethanesulfonate and the like with a compound of general formula (IV) where X, Y and A are as defined in general formula (I),

in a suitable organic solvent in the presence of an appropriate base to give a compound of general formula (V), The compound of general formula (V) represents a compound of general formula (I) where n represents zero. b) oxidizing the compound of general formula (V) with a suitable oxidizing agent to obtain a compound of general formula (I). The compound of general formula (I) can be either a sulfoxide (n = 1) or a sulfone (n = 2) depending on the nature and amount of oxidizing agent used.

The reaction of compound of general formula (III) with a compound of general formula (IV) to produce a compound of general formula (V) may be carried out in the presence of organic

solvents such as methanol, ethanol, acetonitrile, tetrahydrofuran, dioxane, dimethyl formamide, dimethylsulfoxide or organic solvents mixed with water. The above reaction may be preferably carried out in the presence of a suitable base. The bases used include, alkali metal hydroxides such as NaOH and KOH, alkali metal carbonates such as K2CO3 Na2CO3 alkaline earth metal carbonate such as CaCO3, alkali metal bicarbonates such as NaHCO3 and the like, alkali metal hydrides such as NaH, KH. Organic bases such as triethylamine, ethyldiisopropyl amine and the like may also be used. Mixture of solvents and I or mixture of bases may be used. The reaction temperature may range from 0 OC to 150 OC preferably 30 OC to 100 OC. The duration of the reaction may range from 1 to 24 h, preferably from 2 to 12 h.

The oxidation of compound of general formula (V) to compound of general formula (I) may be carried out using oxidizing agents generally used for this reaction and is not critical and include m-chloroperoxybenzoic acid, hydrogen peroxide, peroxyacetic acid, trifluoroperoxyacetic acid, vanadium pentoxide, sodium metaperiodate, peroxymaleic acid, monoperoxyphthalic acid, nitric acid, dinitrogen tetroxide, catalytic OsO4 in the presence of excess of oxidizing agent, iodoxobenzene, chlorobenzotriazole, N-halosuccinimide, t-butylhypochlorite, sodium hypochlorite, MnO2, CrO3, ceric ammonium nitrate and the like. The reaction may be carried out either in organic solvent or in aqueous organic medium. Solvents used in the oxidation may be chlorinated hydrocarbons such as dichloromethane, chloroform, aromatic hydrocarbons such as benzene, toluene and the like, or lower alcohols such as methanol, ethanol and the like. The oxidation reaction may be carried out at a temperature in the range of -78 OC to 100 OC preferably from 30 OC to -70 OC. The duration of the reaction may range from 5 min to 4 h preferably from 5 minto 2 h.

In another embodiment of the present invention, the compound of general formula (I) can also be prepared by reacting a compound of general formula (VI) where Rl, R2, R3 and R4 are as defined earlier with a compound of general formula (VII) where X, Y and A are as defined earlier,

to yield a compound of general formula (V) as defined earlier which is further oxidized as described above.

The reaction of compound of general formula (VI) with a compound of general formula (VII) to produce a compound of general formula (V) may be carried out in the presence of organic solvents such as methanol, ethanol, acetonitrile, tetrahydrofuran, dioxane, dimethyl formamide, dimethylsulfoxide or organic solvents mixed with water. The above reaction may be preferably carried out in the presence of a suitable base. The bases used include, alkali metal hydroxides such as NaOH and KOH, alkali metal carbonates such as K2CO3, Na2CO3, alkaline earth metal carbonates such as CaCO3, alkali metal bicarbonates such as NaHCO3 and the like, alkali metal hydrides such as NaH, KH. Organic bases such as triethylamine, ethyldiisopropyl amine and the like may also be used. Mixture of solvents and / or mixture of bases may be used. The reaction temperature may range from 0 OC to 150 OC preferably 30 oC to 100 OC. The duration ofthe reaction may range from 1 to 24 h, preferably from 2 to 12 h.

In yet another embodiment of the present invention, the compound of general formula (I) can also be prepared by reaction of a compound of general formula (VIII) where Rl, R2, R3 and R4 are as defined earlier, with a compound of general formula (IX) where X, Y and A are as defined earlier, followed by oxidation of the resulting compound (V) as described earlier,

The reaction of compound of general formula (VIII) with a compound of general formula (IX) may be carried out in polar solvents such as HMPA, acetonitrile, water, acetic acid and the like in the presence of strong acids such as conc. HCl. Temperature in the range of 50 "C to 180 "C may be used.

Alternatively, the compound of formula (I) can also be prepared by reacting a compound of general formula (X) where R', R2, R3 are as defined earlier and Z represents a leaving group such as halogen, especially chlorine and bromine or a thioalkyl group, with a compound of general formula (XI) where X, Y, n, R4 and A are as defined earlier, R7 represents hydrogen or a nitrogen protecting group such as benzyl, acyl, alkoxycarbonyl, aryloxycarbonyl and the like, and M represents an alkali metal such as Li, Na, K and the like.

The protecting group is removed after the reaction.

The reaction of compound of general formula (X) with a compound of general formula (XI) may be carried out in an inert solvent such as ether, THF, DMSO, DMF and the like.

Temperature in the range 0 "C to 150 OC may be used. The duration of the reaction may be 1 - 24 h especially 2 - 12 h.

The compound of the general formula (III) can be prepared by known methods (J : Med.

Chewy. 1992, 35, 1049 - 57) by using appropriately substituted pyridines.

The novel intermediate of the general formula (IV) where X and Y may be same or different and independently represent a hydrogen, halogen, optionally halogenated (C,-C6) alkoxy group, or optionally halogenated -C6)alkyl group; A represents a substituted or unsubstituted, 3 to 7 membered nitrogen containing heterocycle excluding substituted or unsubstituted pyrroles; A may further contain one or more heteroatoms selected from N, O, S or a group NR5 where Rs represents hydrogen, (C,-C6) alkyl, aralkyl, acyl, alkoxycarbonyl, aryloxycarbonyl, or aralkoxycarbonyl groups; the heterocycle A, is linked specifically through N- atom to the benzimidazole moiety; the group A may be saturated or may contain one or more double bonds, used in the preparation of compound of general formula (I) in the processes described above may be prepared utilizing types of reactions known to one skilled in the art.

The compound of general formula (XII) where X and Y are as defined earlier, and J represents F or Cl atom may be converted to a compound of formula (XIV) where X, Y and J are as defined earlier and R8 represents a lower alkyl group, by using known methods (Chem. Pharm.

Bull., 37, 1517 (1989); US Patent No. 4,758,579) The compound of formula (XIV) may be converted to a compound of formula (XVI) using a nitrogen containing heterocycle of formula (XV), such as morpholine, piperidine,

pyrrolidine, hexahydroazepine, 4-methylpiperazine, imidazole and the like mentioned earlier.

The reaction may be carried out in the presence of a base such as alkalis like sodium hydroxide, potassium hydroxide, alkali metal carbonates like sodium carbonate, potassium carbonate and the like in solvents such as DMSO, DMF, DME and the like. The reagent may be used in 1 to 10 equivalents, preferably 3 to 5 equivalents. The reaction temperature may range from 0 OC to 150 OC, preferably from 30 °C to 120 OC. The reaction may be conducted for 1 to 24 h, preferably 6to 12h.

The compound of formula (XVI) may be converted to compound of formula (XVII) by using conventional hydrolysis under basic conditions using alkalis such as sodium hydroxide, potassium hydroxide and the like in presence of solvents such as alcohols like methanol, ethanol and the like. The reagent may be used in 1 to 10 equivalents, preferably 3 to 5 equivalents. The reaction temperature may range from - 10 oC to 50 OC, preferably from 0 OC to 30 OC and the duration of the reaction may range from 1 to 24 h, preferably 6 to 10 h. The base and solvent used for the reaction is not critical.

The compound of the formula (XVII) may be converted to a compound of formula (IX) under conventional reduction conditions. The reduction may be carried out in the presence of gaseous hydrogen and a catalyst such as Pd/C, Rh/C, Pt/C or using SnCl2 / HCl or iron / HCl.

The reaction may also be conducted in the presence of solvents such as methanol, ethanol, ethyl acetate, dioxane and the like. The catalyst may be 5 - 10 % of metal on carbon, the amount of catalyst may range from 10 - 20 % w/w and the reaction may be carried out at atmospheric pressure.

The compound of formula (IX) may be converted to compound of formula (IV) by using potassium ethyl xanthate or carbon disulfide in the presence of an alkali such as sodium hydroxide or potassium hydroxide. The reaction may be conducted in the presence of solvents such as methanol or ethanol and the temperature may range from 0 OC to 150 OC preferably at 30 OC to 80 OC. The duration ofthe reaction may range from 0.5 to 12 h, preferably 2 to 6 h.

The pharmaceutically acceptable salts are prepared by reacting the compound of formula (I) with 1 to 4 equivalents of a base such as sodium hydroxide, sodium methoxide, sodium

hydride, potassium hydroxide, lithium hydroxide, potassium t-butoxide, calcium hydroxide, magnesium hydroxide and the like, in solvents like ether, acetone, THF, methanol, t-butanol, dioxane, isopropanol, ethanol etc. Mixture of solvents may be used. Organic bases like lysine, arginine, tryptophan, methionine, diethanolamine, choline, guanidine and their derivatives etc. may also be used. Alternatively, acid addition salts are prepared by treatment with acids such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, p- toluenesulphonic acid, methanesulfonic acid, acetic acid, citric acid, maleic acid salicylic, acid, hydroxynaphthoic acid, ascorbic acid, palmitic acid, succinic acid, benzoic acid, benzene sulfonic acid, tartaric acid, aminobenzoic acid, hydroxybenzoic acid, pyruvic acid, phenylacetic acid, and the like in solvents like ethyl acetate, ether, alcohols, acetone, THF, dioxane etc. Mixture of solvents may also be used.

The compound of formula (I) where n = 1 is a chiral compound. Therefore, the present invention also relates to both the enantiomers, their mixtures or racemic mixture. The stereoisomers of the compounds forming part of this invention may be prepared by using reactants in their single enantiomeric form in the process wherever possible or by conducting the reaction in the presence of reagents or catalysts in their single enantiomer form or by resolving the mixture of stereoisomers by conventional methods. Some of the preferred methods include use of microbial resolution, resolving the diastereomeric salts formed with chiral acids such as mandelic acid, camphorsulfonic acid, tartaric acid, lactic acid and the like or chiral bases such as brucine, cinchona alkaloids and their derivatives and the like.

The single enantiomers can also be obtained by the optical purification of the enantiomerically enriched mixture in which the racemate can be selectively precipitated from a suitable solvent. Preferable solvents for crystallization may be a ketone such as acetone or 2- butanone or an ester such as ethyl acetate, or an alcohol such as ethanol or a nitrile such as acetonitrile, or a hydrocarbon such as toluene or a mixture of organic solvents which may additionally comprise water.

Various polymorphs of compound of general formula (I) forming part of this invention may be prepared by crystallization of compound of formula (I) under different conditions. For

example, using different solvents commonly used or their mixtures for recrystallization; crystallizations at different temperatures; various modes of cooling, ranging from very fast to very slow cooling during crystallizations. Polymorphs may also be obtained by heating or melting the compound followed by gradual or slow cooling. The presence of polymorphs may be determined by solid probe NMR spectroscopy, IR spectroscopy, differential scanning calorimetry, powder X-ray diffraction or such other techniques.

The present invention also provides a pharmaceutical composition, containing the compounds of the general formula (I), as defined above, their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates in combination with the usual pharmaceutically employed carriers, diluents and the like, useful for prophylaxis and / or treatment of gastric and duodenal ulcers, as cytoprotective agents for gastrointestinal tract and as antibacterial agents more specifically as bactericides for Helicobacter pylori.

The pharmaceutical composition may be in the forms normally employed such as for oral use, tablets, capsules, powders, syrups, solutions, suspensions, sustained release formulations, enteric- coated capsules or for paranteral use, injections. These are normally prepared by using pharmaceutically acceptable additives, carriers, diluents, sterile media and the like by using methods well known to those skilled in the art.

The compound of the formula (I) as defined above are clinically administered to mammals, including man, via either oral or parenteral routes. Administration by the oral route is preferred, being more convenient and avoiding the possible pain and irritation of injection. However, in circumstances where the patient cannot swallow the medication, or absorption following oral administration is impaired, as by disease or other abnormality, it is essential that the drug be administered parenterally. By either route, the dosage is in the range of about 1 mg to about 1000 mg (70 kg body weight) per day administered singly or as a divided dose. However, the optimum dosage for the individual subject being treated will be determined by the person responsible for treatment, generally smaller doses being administered initially and thereafter increments made to determine the most suitable dosage.

The dose may remarkably vary depending upon the patient, age and the kind of ulcers.

Suitable pharmaceutically acceptable carriers include solid fillers or diluents and sterile aqueous or organic solutions. The active compound will be present in such pharmaceutical compositions in the amounts sufficient to provide the desired dosage in the range as described above. Thus, for oral administration, the compounds can be combined with a suitable solid or liquid carrier or diluent to form capsules, tablets, powders, syrups, solutions, suspensions and the like. The pharmaceutical compositions, may, if desired, contain additional components such as flavourants, sweeteners, excipients and the like. For parenteral administration, the compounds can be combined with sterile aqueous or organic media to form injectable solutions or suspensions. For example, the injection can be prepared by mixing the active ingredient with pH adjusting buffers, stabilizers, solubilizing agent or the like.

The invention is explained in detail in the examples given below which are provided by way of illustration only and therefore should not be construed to limit the scope of the invention.

Preparation 1 6-Fluoro-5-(imidazol-l-yl)-2-mercapto-1H Step 1 Acetic anhydride (30 mL) was added at room temperature dropwise to 3-chloro-4-fluoroaniline (13.0 g, 0.1 mol) and stirred for 3 h. The reaction mixture was poured on ice (300 g) and the solid was filtered and dried to afford N-(3-chloro-4-fluorophenyl)acetamide (18.4 g, 98 %) as a white solid. mp 96 - 97 oC ; IR (KBr) 3303, 1671 cm-1; 1H NMR (CDCl3) 6 2.20 (s, 3H, CH3), 7.05

(t, J = 8.9 Hz, 1H), 7.28 (m, 1H), 7.66 (d, J = 4,6 Hz, 1H), 8.05 (s, 1H, NH); Mass (m/z) 187 (M+.).

Step 2 The compound (18.0 g, 0.1 mol) (obtained in step 1 above) was dissolved in dichloromethane (100 mL) and was added to a mixture of conc. HNO3 (12 mL) and conc. H2SO4 (15 mL) (3 eq) dropwise at 0 oC and stirred for 10 h. The dichloromethane was removed under reduced pressure and the reaction mixture was poured on ice (300 g). The solid was filtered and dried to yield N- (2-nitro-4-fluoro-5-chlorophenyl)acetamide (18.5 g, 80 %) as a yellow solid. mp 109 - 110 oC ; IR (KBr) 3380, 1703, 1586 cm-1; 1H NMR (CDCl3) 6 2.30 (s, 3H, CH3), 8.00 (d, J = 6.6 Hz, 1H), 9.00 (d, J = 6.8 Hz, 1H), 10.30 (s, 1H, NH); Mass (m/z) 232 (M+).

Step 3 The acetamide (18.5 g, 0.08 mol) (obtained in step 2 above) was dissolved in dimethyl sulfoxide (50 mL) and added to a well stirred mixture of imidazole (27.0 g, 0.4 mol), KOH (7.0 g, 0.12 mol) and dimethyl sulfoxide (50 mL). The mixture was stirred at 80 oC for 12 h and poured on ice (400 g). The resultant solid was filtered and dried to yield 2-nitro-4-fluoro-5-(imidazol-1- yl)aniline (12.5 g, 70 %) as a brown solid. mp 122 - 123 oC ; IR (KBr) 3473, 1528 cm-1; 1H NMR (DMSO-d6) 6 7.18 (d, J = 5.8 Hz, 1H), 7.22 (d, J = 6.9 Hz, 1H), 7.45 (brs, 2H, NH2), 7.60 (s, 1H), 8.06 (m, 2H); Mass (m/z) 222 (M+).

Step 4 The nitroaniline derivative (12.5 g, 0.056 mol) (obtained in step 3 above) was hydrogenated in ethanol (50 mL) over 10 % Pd-C (1.0 g) in an atmosphere of hydrogen at ca 25 oC. The catalyst was filtered through a celite bed and concentrated to afford 4-fluoro-5-(imidazol-1-yl)-1,2- phenylenediamine (7.0 g, 64 %) as a brown viscous oil. IR (Neat) 3351 cm-1; 1H NMR (DMSO- d6)# 5.00 (brs, 4H, 2 x NH2), 6.50 (d, J = 9.6 Hz, 1H), 6.60 (d, J = 6.3 Hz, 1H), 7.08 (s, 1H), 7.32 (s, 1H), 7.80 (s, 1H); Mass (m/z) 192 (M+.).

Step 5 The diamine (6.7 g, 0.035 mol) (obtained in step 4 above) was dissolved in ethanol (20 mL) and added to a stirred mixture of carbon disulfide (3.0 g, 0.04 mol), potassium hydroxide (2.3 g, 0.04 mol), water (5 mL) and ethanol (15 mL). The resultant solution was refluxed for 6 h. Animal

charcoal (2.0 g) was added and further refluxed for 1h. The mixture was filtered and washed with hot water. A mixture of acetic acid and water (1 : 2, 15 mL) was added to the filtrate slowly with vigorous stirring to separate 6-fluoro-5-(imidazol-1-yl)-2-mercapto-lH-benzimidazole (5.0 g, 60 %) as a brown solid. mp 280 oC (decomp.); IR (KBr) 3078, 1481 cm-1; 1H NMR (DMSO-d6) 5 2.20 (s, 1H, SH), 7.10 (s, 1H), 7.24 (d, J = 6.0 Hz, 1H), 7.26 (d, J = 4.1 Hz, 1H), 7.56 (s, 1H), 8.00 (s, 1H), 12.90 (brs, 1H, NH); Mass (m/z) 234 (M+.).

Preparation 2 6-Fluoro-5-(morpholin-l-yl)-2-mercapto-l Step 1 2=Nitro-4-fluoro-5-(morpholin-1-yl)aniline (14.5 g, 70 %) was prepared by an analogous procedure as described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5- chlorophenyl)acetamide (20.0 g, 0.086 mol), (obtained in preparation 1, step 2), morpholine (37.0 g, 0.43 mol), potassium hydroxide (5.8 g, 0.1 mol) and dimethyl sulfoxide (100 mL). mp 141-142 °C; IR (KBr) 3446, 1254 m-1; 1H NMR (CDCl3) 5 3.20 (t, J = 4.2 Hz, 4H, N(CH2)2), 3.90 (t, J = 4.4 Hz, 4H, O(CH2)2), 6.00 (d, J = 5.8 Hz, 1H), 6.10 (brs, 2H, NH2), 7.80 (d, J = 10.4 Hz, 1H); Mass (m/z) 241 (M+).

Step 2 The nitroaniline derivative (14.0 g, 0.058 mol) (obtained in step 1 above) was hydrogenated using 10 % Pd-C (3.0 g) in ethanol (75 mL) (as described in preparation 1, step 4) to yield 4-fluoro-5- (morpholin-1-yl)-1,2-pyenylenediamine (11.0 g, 90 %) as a brown viscous oil. IR (Neat) 3347 cm-1; 1H NMR (DMSO-d6) å 3. 12 (m, 4H, N(CH2)2), 3.80 (m, 4H, O(CH2)2), 5.80 (brs, 4H, 2 x NH2), 6.28 (d, J = 5.9 Hz, 1H), 6.36 (d, J = 9.8 Hz, 1H); Mass (m/z) 211 (M+.).

Step 3 6-Fluoro-5-(morpholin-1-yl)-2-mercapto-1H-benzimidazole (10.0 g, 76 %) was prepared by the procedure described in preparation 1 (step 5) using the diamine (11.0 g, 0.052 mol) (obtained in step 2 above), carbon disulfide (4.75 g, 0.062 mol), potassium hydroxide (3.5 g, 0.062 mol), ethanol (60 mL) and water (10 mL). mp 289 oC (decomp.); IR (KBr) 3124, 1485 cm-1; 1H NMR (DMSO-d6+CDC3)# 2.28 (s, 1H, SH), 3.02 (m, 4H, N(CH2)2), 3.90 (m, 4H, O(CH2)2), 6.90 (d, J = 5.6 Hz, 1H), 7.00 (d, J = 10.2 Hz, 1H), 12.38 (brs, 1H, NH); Mass (m/z) 253 (M+.).

Preparation 3 6-Fluoro-5-(piperidin-1-yl)-2-mercapto-lH-benzimidazole : Step 1 2-Nitro-4-fluoro-5-(piperidin-1-yl)aniline (13.0 g, 52%) was prrepared by an analogous procedure as described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5-chloro phenyl)acetamide (25.0 g, 0.107 mol) (obtained in preparation 1, step 2), piperidine (45.8 g, 0.537 mol), potassium hydroxide (9.0 g, 0.16 mol) and dimethyl sulfoxide (100 mL). mp 112-113 cC. IR (KBr) 3472, 1234 cm-1; 1H NMR (CDCl3) 8 1.60 (m, 2H, CH2), 1.70 (m, 4H, (CH2)2), 3.22 (m, 4H, N(CH2)2), 5.88 (d, J = 7.6 Hz, 1H), 6.08 (brs, 2H, NH2), 7.78 (d, J = 14.2 Hz, 1H) ; Mass (m/z) 239 (M+.).

Step 2 The nitroaniline derivative (6.2 g, 0.026 mol) (obtained in step 1 above) was hydrogenated using 10 % Pd-C (1.0 g) in ethanol (30 mL), using an analogous procedure as described in preparation 1 (step 4) to yield 4-fluoro-5-(piperidin-1-y1)-1,2-phenylenediamine (5.3 g, 98 %) as brown viscous oil. IR (Neat) 3346 cm-1; 1H NMR (CDCl3) 8 1.54 (m, 2H, CH2), 1.70 (m, 4H, (CH2)2),

2.90 (m, 4H, N(CH2)2), 3.10 (brs, 4H, 2 x NH2), 6.40 (d, J = 8.8 Hz, 1H), 6.48 (d, J = 13.8 Hz, 1H); Mass (m/z) 209 (M+.).

Step 3 6-fluoro-5-(piperidin-1-yl)-2-mercapto-lH-benzimidazole (3.6 g, 64 %) was prepared by a similar procedure as described in preparation 1 (step 5) using the diamine (4.5 g, 0.022 mol) (obtained in step 2 above), carbon disulfide (2.2 g, 0.029 mol), potassium hydroxide (1.6 g, 0.029 mol), ethanol (25 mL) and water (5 mL). mp 275 oC (decomp.); IR (KBr) 3122, 1486 cm-1; 1H NMR (CD30D) # 1.58 (m, 2H, CH2), 1.76 (m, 4H, (CH2)2), 2.98 (t, J = 5.6 Hz, 4H, N(CH2)2), 6.90 (d, J = 7.4 hz, 1H), 7.00 (d, J = 11.6 Hz, 1H); Mass (m/z) 251 (M+.).

Preparation 4 6-Fluoro-5-(4-methylpiperazin-1-yl)2-mercapto-1H-benzimidiaz ole: Step 1 N-[2-Nitro-4-fluoro-5-(4-methylpiperain-1 -yl)phenyl]acetamide (25.0 g, 80 %) was prepared by an analogous procedure as described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5- chlorophenyl)acetamide (25.0 g, 0.107 mol) (obtained in preparation 1, step 2), 4- methylpiperazine (53.5 g, 0.535 mol), potassium hydroxide (9.05 g, 0.16 mol) and dimethyl sulfoxide (100 mL). mp90- 91 °C; IR (KBr) 3339, 1707, 1582, cm-1; 1H NMR (CDCl3) # 2.24 (s, 3H, CH3), 2.32 (s, 3H, CH3), 2.56 (t, J 5.0 Hz, 4H, N(CH2)2), 3.42 (t, J = 5.0 Hz, 4H, N(CH2)2), 7.90 (d, J = 14.1 Hz, 1H), 8.36 (d, J = 8.4 Hz, 1H), 10.70 (brs, 1H, NH); Mass (m/z) 296 (M+.).

Step 2

The acetamide (25.0 g, 0.085 mol) (obtained in step 1 above) was dissolved in methanol (160 mL) and 6 M NaOH solution (42 mL) was added dropwise at ca 30 oC and stirred for 6 h. The mixture was cooled in an ice bath and water (300 mL) was added dropwise. The resultant precipitate was collected by filtration and dried to yield 2-nitro-4-fluoro-5-(4-methylpiperazin- 1- yl)aniline (16.0 g, 75 %) as a brown solid. mp 154 - 155 oC ; IR (KBr) 3383, 1247 cm-1; 1H NMR (CDCl3 ) 8 2.32 (s, 3H, CH3), 2.54 (t, J = 5.0 Hz, 4H, N(CH2)2), 3.24 (t, J = 4.6 Hz, 4H, N(CH2)2, 6.02 (d, J = 7.5 Hz, 1H), 6.12 (brs, 2H, NH2), 7.74 (d, J = 14.0 Hz, 1H); Mass (m/z) 254 (M+.).

Step 3 The nitroaniline derivative (16.0 g, 0.063 mol) (obtained in step 2 above) was hydrogenated using 10 % Pd-C (2.5 g) in ethanol (60 mL) by an analogous procedure as described in preparation 1 (step 4) to yield 4-fluoro-5-(4-methylpiperazin-1-yl)-1,2-phenylenedamine (13.2 g, 94 %) as a brown viscous oil. IR (Neat) 3332 cm-1; 1H NMR (DMSO-d6) 8 2.34 (s, 3H, CH3), 2.62 (t, J = 4.2 Hz, 4H, N(CH2)2), 3.08 (t, J = 4.4 Hz, 4H, N(CH2)2), 3.30 (brs, 4H, 2 x NH2), 6.40 (d, J = 8.2 Hz, 1H), 6.48 (d, J = 12.8 Hz, 1H) ; Mass (m/z) 224 (M+.).

Step 4 6-Fluoro-5-(4-methylpiperazin-1-yl)-2-mercapto-1H-benzimidaz ole (15.0 g, 94%) was prepared by a similar procedure to that described in preparation 1 (step 5) using the diamine (14.0 g, 0.06 mol) (obtained in step 3 above), carbon disulfide (6.1 g, 0.08 mol), potassium hydroxide (4.49 g, 0.08 mol), ethanol (70 mL) and water (10 mL). mp 290 oC (decomp.); IR (KBr) 3088, 1481 cm-1; 1H NMR (DMSO-d6) 8 2.24 (s, 3H, CH3), 2.50 (t, J = 4.3 Hz, 4H, N(CH2)2), 3.00 (t, J = 4.4 Hz, 4H, N(CH2)2), 6.78 (d, J = 7.3 Hz, 1H), 7.00 (d, J = 11.9 Hz, 1H); Mass (m/z) 266 (M+.).

Preparation 5 6-Fluoro-5-(4-t-butyloxycarbonylpiperazin-1-yl)-2-mercapto-1 H-benzimidazole:

Step 1 2-Nitro-4-fluor-5-(piperazin-1-yl)aniline (5.6 g, 77 %) was prepared by a procedure analogous to that described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5-chlorophenyl)acetamide (7.4 g, 0.03 mol) (obtained in preparation 1, step 2), piperazine (27.2 g, 0.3 mol), potassium hydroxide (2.5 g, 0.045 mol) and dimethyl sulfoxide (30 mL). mp 120 - 121 OC ; 1K (KBr) 3334, 1504, 1251 cm-1; 1H NMR (CDCl3+CD30D) â 3.00 (t, J = 5.4 Hz, 4H, N(CH2)2); 3.20 (t, J = 5.6 Hz, 4H, N(CH2)2), 3.82 (brs, 3H, NH), 6.18 (d, J = 8.2 Hz, 1H), 7.74 (d, J = 13.8 Hz, 1H); Mass (m/z) 240 (M+.).

Step 2 The nitroaniline derivative (5.6 g, 0.023 mol) (obtained in step 1 above) was hydrogenated using 10 % Pd-C (1.0 g) in ethanol (25 mL), using a procedure analogous to that described in preparation 1 (step 4) to yield 4-fluoro-5-(piperazin-1-yl)-1,2-phenylenediamin (4.7 g, 98 %) as a brown viscous oil. IR (Neat) 3283 cm-1; 1H NMR (CDCl3) å 2.80 (brs, 5H, NH), 2.94 (m, 4H, N(CH2)2), 3.06 (m, 4H, N(CH2)2), 6.42 (d, J = 7.8 Hz, 1H), 6.47 (d, J = 12.4 Hz, 1H); Mass (m/z) 210 (M+.).

Step 3 6-Fluoro-5-(piperazin-1-yl)-2-mercapto-lH-benzimidazole (4.3 g, 80 %) was prepared by an analogous procedure as described in preparation 1 (step 5) using the diamine (4.5 g, 0.021 mol) (obtained in step 2 above), carbon disulfide (1.9 g, 0.025 mol), potassium hydroxide (1.4 g, 0.025 mol), ethanol (25 mL) and water (5 mL). mp 100 - 101 OC; IR (KBr) 3133, 1482 cm-1 ; 1HNMR (DMSO-d6) å 2.25 (s, 1H, SH), 2.90 (m, 4H, N(CH2)2), 4.10 (brs, 1H, NH), 4.48 (m, 4H,

N(CH2)2), 6.80 (d, J = 8.4 Hz, 1H), 7.00 (d, J = 12.3 Hz, 1H), 12.30 (brs, 1H, NH); Mass (m/z) 252 (M+.).

Step 4 A mixture of 6-fluoro-5-(piperazin-1-yl)-2-mercapto-1H-benzimidazole (4.3 g, 0.017 mol) (obtained in step 3 above), di-t-butyldicarbonate (4.4 g, 0.02 mol), 1N NaOH solution (20 mL, 0.02 mol) and dioxane (10 mL) was stirred for 12 h at ca 30 OC. The reaction mixture was diluted with chloroform and washed with water and brine solution. The organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure. The residue was purified by silica gel column chromatography using 1 : 3 EtOAc - pet. ether to afford 6-fluoro-5-(4-t- butyoxypiperazin-1-yl)-2-mercapto-1H-benzimidazole (3.3 g, 55 %) as a yellow solid. mp 111 - 112 OC; IR (KBr) 3084, 1701, 1485 cm-1; 1H NMR (CDCl3+CD30D) 6 1.48 (s, 9H, 3 x CH3), 2.22 (s, 1H, SH), 3.00 (t, J = 4.8 Hz, 4H, N(CH2)2), 3.60 (t, J = 4.7 Hz, 4H, N(CH2)2), 6.80 (d, J = 7.7 Hz, 1H), 7.00 (d, J = 12.2 Hz, 1H), 11.52 (brs, 1H, NH); Mass (m/z) 352 (M+.).

Preparation 6 6-Fluoro-(5-(4-ethylenedioxy)piperidin-1-yl)-2-mercapto-1H-b enzimidazole : Step 1 N- [2-Nitro-4-fluoro-(5-(4-hydroxy)piperidin 1 -yl)phenyl]acetamide (22.0 g, 86%) was prepared by an analogous procedure to that described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5- chlorophenyl)acetamide (20.0 g, 0.086 mol) (obtained in preparation 1, step 2), 4- hydroxypiperidine (34.4 g, 0.34 mol), potassium hydroxide (7.3 g, 0.13 mol) and dimethyl <BR> <BR> <BR> sulfoxide (80 mL). IR (KBr) 3432, 1682, 1518 cm', H NMR (CDCl3) #d 1.65 - 1.78 (m, 2H, CH2), 1.99-2.02 (m, 2H, CH2), 2.28 (s, 3H, CH3), 3.13-3.26 (m, 2H, CH2), 3.66 - 3.77 (m, 2H,

CH2), 3.96 - 3.98 (m, 1H, CH), 7.90 (d, J = 14.0 Hz, 1H), 8.42 (d, J = 8.6 Hz, 1H), 10.76 (brs, 1H, NH); Mass (m/z) 297 (M+.).

Step 2 The acetamide (10.0 g, 0.034 mol) (obtained in step 1 above) was dissolved in anhydrous dichloromethane (30 mL) and cooled to 0 eeC, to which a mixture of pyridinium chloro chromate (10.4 g, 0.05 mol) and celite (10 g) was added and stirred for 10 h. The reaction mixture was filtered through celite pad and the filtrate was washed with sodium bicarbonate solution, brine and dried over anhydrous sodium sulfate. Removal of solvent under reduced pressure afforded N-[2-nitro-4-fluoro-5-(4-piperidon-1-yl)phenyl]acetamide (10.0 g, 99%). mp 142-143 eeC ; IR (KBr) 1728, 1699, 1509 cm-1;1H NMR (CDCl3) 6d 2.29 (s, 3H, CH3), 2.64 (t, J = 6.1 Hz, 4H, (CH2) 2), 3.75 (t, J = 5.8 Hz, 4H, N(CH2)2), 8.00 (d, J = 13.8 Hz, 1H), 8.50 (d, J = 8.6 Hz, 1H), 10.72 (brs, 1H, NH); Mass (m/z) 295 (M+.).

Step 3 A mixture of the above compound (5.0 g, 0.017 mol) (obtained in step 2 above), 1,2-ethanediol (1.0 g, 0.034 mol), p-toluenesulphonic acid (catalytic amount) and benzene (20 mL) was refluxed for 2 h using Dean-Stark apparatus. The reaction mixture was diluted with ethyl acetate (50 mL) and washed with sodium bicarbonate solution and brine. The organic layer was dried over <BR> <BR> <BR> <BR> na2SO4 and concentrated to yield N-[2-nito-4-fluoro-5-(4-(ethylenedioxy)piperidin-1- 1- yl)phenyl]acetamide (5.5 g, 96 %). mp 116-117 eeC; IR (KBr) 3321, 1693, 1510 cm-1; HNMR (CDCl3) #d 1.85 (t, J = 5.6 Hz, 4H, (CH2)2), 2.27 (s, 3H, CH3), 3.52 (t, J = 5.6 Hz, 4H, N(CH2)2), 3.99 (s, 4H, O(CH2)2O), 7.88 (d, J = 14.2 Hz, 1H), 8.40 (d, J = 8.6 Hz, 1H), 10.75 (brs, 1H, NH); Mass (m/z) 339 (M+.).

Step 4 The above compound (5.5 g, 0.016 mol) (obtained in step 3) was deacetylated by an analogous procedure to that described in preparation 4 (step 2) using 6 M NaOH solution (10 mL) and methanol (20 mL) to afford 2-nitro-4-fluoro-5-(4-ethylenedioxy)piperidin- 1 -yl)aniline (4.5 g, 95 %). mp 136-137 #°C; IR (KBr) 3336, 1633, 1514 cm-1;1H NMR (CDCl3) 5d 1.85 (t, J = 5.5 Hz,

4H, (CH2) 2), 3.35 (t, J = 5.7 Hz, 4H, N(CH2)2), 4.00 (s, 4H, O(CH2)2O), 6.00 (d, J = 7.6 Hz, 1H), 6.02 (brs, 2H, NH2), 7.79 (d, J = 14.0 Hz, 1H); Mass (m/z) 297 (M+.).

Step 5 The nitroaniline derivative (7.8 g, 0.026 mol) (obtained in step 4 above) was hydrogenated using 10% Pd-C (3.0 g) in ethyl acetate (50 mL) as described in preparation 1 (step 4) to yield 4-fluoro- 5-(4-ethylenedioxy)piperidin-1-yl)-1,2-phenylenediamine (6.8 g, 99%) as a brown viscous oil.

IR (Neat) 3328, 1521 cm01; 1H NMR (CDCl3) #d 1.86 (t,J=5.6 Hz, 4H, (Ch2)2), 2.95 (brs, 4H, 2xNH2), 3.03 (t, J = 5.7 Hz, 4H, N(CH2)2), 4.00 (s, 4H, O(CH2)2O), 6.40 (d, J = 8.0 Hz, 1H), 6.46 (d, J = 14.5 Hz, 1H); Mass (m/z) 267 (M+.).

Step 6 6-Fluoro-5-(4-(ethylenedioxy)piperidin- 1-yl)-2-mercapto-1H-benzimidazole (2.0 g, 43%) was prepared by a similar procedure to that described in preparation 1 (step 5) using above diamine (4.0 g, 0.015 mol) (obtained in step 5 above), carbon disulfide (2.2 g, 0.018 mol), ethanol (20 mL) and water (4 mL). mp 160-161 eeC; IR (KBr) 3125, 1482 cm-1; 1H NMR (CD30D) #d 1.86 (t, J = 5.8 Hz, 4H, (CH2) 2), 3.10 (t, J = 5.6 Hz, 4H, N(CH2)2), 3.98 (s, 4H, O(CH2)2O), 6.91 (d, J = 7.5 Hz, 1H), 6.95 (d, J = 11.6 Hz, 1H); Mass (m/z) 309 (M+.).

Preparation 7 6-Fluoro-5-(4-piperidon-1-yl)-2-mercapto-lH-benzimidazole : A mixture of 6-fluoro-(5-(4-ethylenedioxy)piperidin- 1 -yl)-2-mercapto- 1 H-benzimidazole (1.0 g, 0.0032 mol) (obtained in preparation 6, step 6), 6 N HCl (25 mL) and acetone (10 mL) was refluxed for 1 h. The reaction mixture was neutralized with cold sodium carbonate solution and extracted with ethyl acetate. The organic layer was washed with brine solution, dried and

concentrated under reduced pressure to afford the title compound (0.5 g, 63 %). mp 260 OC (decomp.); IR (KBr) 3069, 1706, 1482 cm-1; 1H NMR (DMSO-d6) 6 2.52 (m, 4H, (CH2)2), 3.26 (m, 4H, N(CH2)2), 6.82 (d, J = 7.4 Hz, 1H), 7.02 (d, J = 11.4 Hz, 1H), 12.52 (brs, 1H, NH); Mass (m/z) 265 (M+.).

Preparation 8 6-Fluoro-5-(4-hydroxylimoino)piperidin-1-yl)-2-mercapto-1H-b ezimidazole: A mixture of 6-fluoro-5-(4-piperidon-1-yl)-2-mercapto-1H-benzimidazole (0.4 g, 0.0015 mol) (obtained in preparation 7), hydroxylamine hydrochloride (0.5 mL), pyridine (0.5 mL) and ethanol (5 mL) was refluxed for 1 h. Ethanol was removed under reduced pressure and water was added to the mixture. The solid separated was filtered and recrystallized from chloroform- methanol mixture to yield the title compound (0.3 g, 75 %). mp 290 OC (decomp.) ; IR (KBr) <BR> <BR> <BR> 3450, 3135, 1486 cm-1; 1H NMR (DMSO-d6) 2.40 (m, 2H, CH2), 2.64 (m, 2H, CH2) 2.30 (m, 4H, N(CH2)2), 6.88 (d, J = 7.4 Hz, 1H), 7.06 (d, J = 11.4 Hz, 1H), 10.46 (brs, 1H, OH), 12.44 (brs, 1H, NH); Mass (m/z) 280 (M+.).

Prearation 9 6-Fluroro-5-(4-hydroxypiperidin-1-yl)-2-mercapto-1H-benzimid azole:

Step 1 N-[2-Nitro-4-fluoro-5-(4-hydroxypiperidin- 1 -yl)phenyl]acetamide (10.0 g, 0.034 mol) (obtained in preparation 6, step 1) was deacetylated using 6 N NaOH solution (20 mL) and methanol (30 mL) using an analogous procedure to that described in preparation 4 (step 2) to afford 2-nitro-4- fluoro-5-(4-hydroxypiperidin-1-yl) aniline (8.4 g, 80 %). mp 238-239 eeC ; IR (KBr) 3357, 3326, 1641 cm ; HNMR(CDCl3) 6d 1.70-1.80 (m, 2H, CH2), 1.99-2.08 (m, 2H, CH2), 2.99-3.12 (m, 2H, NCH2), 3.50 - 3.62 (m, 2H, NCH2), 3.94 (m, 1H, CH), 6.0 (d, J = 7.4 Hz, 1H), 6.02 (brs, 2H, NH2), 7.80 (d, J = 14.2 Hz, 1H); Mass (m/z) 255 (M+.).

Step 2 The nitroaniline derivative (8.0 g, 0.03 mol) (obtained in Step 1 above) was hydrogenated using 10% Pd-C (2.0 g) in ethyl acetate (30 mL) by an analogous procedure to that described in preparation 1 (step 4) to yield 4-fluoro-5-(4-hydroxypiperidin-1-yl)-1,2-phenylene diamine (8.5 g, 99%) as a brown viscous oil. IR (Neat) 3426, 3270, 1620 cm-1; 1H NMR (CDCl3 + DMSO-d6) 5d 1.60 - 1.78 (m, 2H, CH2), 1.82 - 2.06 (m, 2H, CH2), 2.62 - 2.78 (m, 2H, NCH2), 3.14 - 3.22 (m, 2H, NCH2), 3.50 (brs, 4H, 2 x NH2), 3.68 - 3.82 (m, 1H, CH), 6.40 (d, J = 7.8 Hz, 1H), 6.48 (d, J = 13.2 Hz, 1H); Mass (m/z) 225 (Mt.).

Step 3 6-Fluoro-5-(4-hydroxypiperidin-1-yl)-2-mercapto-1H-benzimida zole (4.5 g, 62%) was prepared by a similar procedure to that described in preparation 1 (step 5) using the diamine (6.0 g, 0.027 mol) (obtained in step 2 above), carbon disulfide (3.9 g, 0.052 mol), ethanol (30 mL) and water (5 mL). mp 268-269 eeC; IR (KBr) 3397, 3124, 1487 cm-1; 1H NMR (DMSO-d6) #d 1.45 - 1.56 (m, 2H, CH2), 1.60 - 1.87 (m, 2H, CH2), 2.24 (s, 1H, SH), 2.64 - 3.92 (m, 2H, NCH2), 3.11 - 3.17 (m, 2H, NCH2), 3.30 - 3.60 (m, 1H, CH), 4.30 (brs, 1H, OH), 6.70 (d, J = 7.4 Hz, 1H), 7.00 (d, J = 12.6 Hz, 1H), 12.00 (brs, 1H, NH); Mass (m/z) 267 (M+.).

Preparation 10 6-Fluoro-5-(hexamethyleneimin-1-yl)-2-mercapto-1H-benzimidaz ole:

Step 1 <BR> <BR> <BR> <BR> 2-Nitro-4-fluoro-5 -(hexamethyleneimin- aniline (8.2 g, 86%) was prepared by an analogous procedure to that described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5- chlorophenyl)acetamide (9.0 g, 0.038 mol) (obtained in preparation 1, step 1-2), hexamethyleneimine (9.16 g, 0.193 mol) and dimethyl sulfoxide (40 mL). mp 129 - l30ccC; IR (KBr) 3465, 3327, 1637, 1521 cm-1; 1H NMR (CDCl3) 6d 1.60 (m, 4H, (CH2)2), 1.84 (m, 4H, (CH2)2), 3.48 (t, J = 5.1 Hz, 4H, N(CH2)2), 5.82 (d, J = 8.0 Hz, 1H), 6.04 (brs, 2H, NH2), 7.74 (d, J = 13.7 Hz, 1H); Mass (m/z) 253 (M+.).

Step 2 The nitroaniline derivative (4.8 g, 0.019 mol) (obtained in step 1) was added in portions to a mixture of stannous chloride dihydrate (13.4 g, 0.59 mol) and conc. HCl (50 mL) at 0 #°C and stirred for 3 h at ca. 30 eeC. The reaction mixture was poured on crushed ice (100 g) and made it alkaline with solid potassium carbonate followed by ammonia solution and extracted with diethyl ether. The ether layer was dried over Na2SO4 and concentrated under reduced pressure to yield 4-fluoro-5-(hexamethyleneimin-1-yl)-1,2-phenylenediamine (4.0 g, 95 %) as a viscous oil. IR (Neat) 3331, 1523 cm ; H NMR (CDCl3) gd 1.62 (m, 4H, (CH2)2), 1.80 (m, 4H, (CH2)2), 3.10 (brs, 4H, 2 x NH2), 3.18 (m, 4H, N(CH2)2), 6.30 (d, J = 8.5 Hz, 1H), 6.44 (d, J = 13.5 Hz, 1H); Mass (m/z) 223 (M+.).

Step 3 6-Fluoro-5-(hexamethyleneimin-1-yl)-2-mercapto-1H-benzimidaz ole (3.3 g, 70%) was prepared by a procedure similar to that described in preparation 1 (step 5) using the diamine (4.0 g, 0.018 mol) (obtained in step 2 above), carbon disulfide (2.72 g, 0.036 mol), potassium hydroxide (2.0

g, 0.036 mol), ethanol (30 mL) and water (5 mL). mp 301-302 eeC; IR (KBr) 3128, 1485 cm-1; H NMR (CDCl3 + DMSO-d6) gd 1.64 (m, 4H, (CH2)2), 1.81 (m, 4H, (CH2)2), 2.54 (s, 1H SH), 3.24 (t, J = 5.1 Hz, 4H, N(CH2)2), 6.72 (d, J = 7.6 Hz, 1H), 6.84 (d, J = 12.1 Hz, 1H), 11.67 (brs, 1H, NH); Mass (m/z) 265 (M+.).

Preparation 11 6-Flu oro-5-(2-methoxymethyl)pyrrolidin-l-yl)- Step 1 2-Nitro-4-fluoro-(5-(2-methoxymethyl)pyrrolidin-1-yl)aniline (4.0 g, 71 %) was prepared by a procedure similar to that described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5- chlorophenyl)acetamide (5.0 g, 0.021 mol) (obtained in preparation 1, step 2), 2-methoxymethyl pyrrolidine (12.35 g, 0.11 mol), potassium hydroxide (1.8 g, 0.032 mol) and dimethyl sulfoxide <BR> <BR> <BR> (20 mL). mp 94-96 °C ; IR (KBr) 3469, 1522 cm ; H NMR (CDCl3) #d 1.92-2.08 (m, 4H, (CH2) 2), 3.18-3.20 (m, 2H, NCH2), 3.30 (s, 3H, OCH3), 3.40-3.68 (m, 2H, CH2O), .20-4.32 (m, 1H, CH), 5.78 (d, J - 7.6 Hz, 1H), 6.08 (brs, 2H, NH2), 7.78 (d, J = 14.4 Hz, 1H); Mass (m/z) 269 (M+.).

Step 2 The nitroaniline derivative (3.0 g, 0.011 mol) (obtained in step 1 above) was reduced by stannous chloride dihydrate (7.56 g, 0.033 mol) and conc. HCl (30 mL) as described in preparation 10 (step 2) to yield 4-fluoro-(5-(2-methoxymethyl)pyrrolidin-1-yl)-1,2-phenylened iamine (2.3 g, 88 %)

as a viscous oil. IR (Neat) 3343, 1523 cm01; 1H NMR (CDCl3) #d 1.82-2.10 (m, 4H, (CH2)2), 3.06 (brs, 4H, 2 x NH2), 3.16-3.20 (m, 2H, NCH2), 3.24 (s, 3H, OCH3), 3.40- 3.54 (m, 2H, CH2O), 3.72 - 3.86 (m, 1H, CH), 6.26 (d, J = 8.3 Hz, 1H), 6.48 (d, J = 13.6 Hz, 1H); Mass (m/z) 239 (M+.).

Step 3 6-Fluoro-5(5-(2-methoxymethyl)pyrrolidin- 1-yl)-2-mercapto-1H-benzimidazolo (3.3 g, 66 %) was prepared by a similar procedure to that described in preparation 1 (step 5) using diamine (4.3 g, 0.018 mol) (obtained in step 2 above), carbon disulfide (2.7 g, 0.036 mol), potassium hydroxide (2.0 g, 0.036 mol), ethanol (30 mL) and water (5 mL). mp 226 - 227 eeC; IR (KBr) 3075, 1478 cm 1; 1H NMR (CDCl3) #d 1.90 - 2.14 (m, 4H, (CH2)2), 3.10-3.18 (m, 2H, NCH2), 3.24 (s, 3H, OCH3), 3.40 - 3.60 (m, 2H, CH2O), 3.98 - 4.06 (m, 1H, CH), 6.62 (d, J = 7.4 Hz, 1H), 6.90 (d, J = 12.2 Hz, 1H), 10.12 (brs, 1H, NH); Mass (m/z) 281 (M+.).

Preparation 12 6-Fluoro-5-(pyrrolidin-1-yl)-2-mercapto-lH-benzimidazole : Step 1 2-Nitro-4-fluoro-5-(pyrrolidin-1-yl)aniline (12.3 g, 85%) was prepared by an analogous procedure to that described in preparation 1 (step 3) using N-(2-nitro-4-fluoro-5-chlorophenyl)acetamide (15.0 g, 0.064 mol) (obtained in preparation 1, step 2), pyrrolidine (22.9 g, 0.32 mol), potassium hydroxide (5.4 g, 0.096 mol) and dimethyl sulfoxide (60 mL). mp 115-116 "C; IR (KBr) 3478, 1536 cm-1; 'H NMR (CDCl3) #d 1.98 (m, 4H, (CH2)2), 3.50 (m, 4H, N(CH2)2), 5.64 (d, J = 7.8 Hz, 1H), 6.09 (brs, 2H, NH2), 7.72 (d, J = 14.6 Hz, 1H); Mass (m/z) 225 (M+.).

Step 2

The nitroaniline derivative (5.0 g, 0.022 mol) (obtained in step 1 above) was reduced using Fe powder (12.6 g, 0.22 mol), conc. HCl (33 mL) and ethanol (33 mL) as described in preparation 10 (step 2) to yield 4-fluoro-5-(pyrrolidin-1-yl)-1,2-metnylenediamine (4.2 g, 97 %) as viscous oil. IR (Neat) 3340, 1524 cm-1; 1H NMR (CDCl3) #d 1.93 (m, 4H, (CH2)2), 3.24(m, 4H, N(CH2)2), 3.56 (brs, 4H, 2 xNH2), 6.18 (d, J = 7.2Hz, 1H), 6.48 (d, J = 13.2 Hz, 1H); Mass (m/z) 195 (M+.).

Step 3 6-Fluoro-5-(pyrrolidin-1-yl)-2-mercapto-1H-benzimidazole (1.77 g, 33%) was prepared by the procedure described in preparation 1 (step 5) using the compound (obtained in step 2 above), (4.5 g, 0.023 mol), carbon disulfide (2.1 g, 0.027 mol), potassium hydroxide (1.56 g, 0.027 mol), ethanol (25 mL) and water (4 mL). mp 170-172#°C; IR (KBr) 3086, 1482 cm';' H NMR (DMSO-d6) 6d 1.88 (m, 4H, (CH2)2), 3.21 (m, 4H, N(CH2)2), 6.50 (d, J = 7.8 Hz, 1H), 6.94 (d, J = 13.9 Hz, 1H); Mass (m/z) 237 (M+.).

Preparation 13 5-(Morpholin-1-yl)-2-mercapto-1H-benzimidazole: Step 1 3-Chloroaniline (75.0 g, 0.59 mol) was acetylated using acetic anhydride (250 mL, 2.95 mol) by an analogous procedure to that described in preparation 1 (step 1) to yield 3-chlorophenyl acetamide (90.0 g, 90 %) as a white solid. mp 70 - 71 oC ; IR (KBr) 3288, 1694 cm-1; 1H NMR (CDCl3) 6 2.20 (s, 3H, CH3), 7.08 (d, J = 8.8 Hz, 1H), 7.22 (t, J = 8.2 Hz, 1H), 7.34 (d, J = 7.9 Hz, 1H), 7.60 (s, 1H), 7.68 (brs, 1H, NH); Mass (m/z) 169 (M+.).

Step 2

(5-Chloro-2-nitrophenyl)acetamide (35.0 g, 30 %) was prepared from 3-chloro phenyl acetamide (90.0 g, 0.53 mol) (obtained in step 1 above), conc. HNO3 (100 mL), conc. H2SO4 (156 mL) and dichloromethane (250 mL), by an analogous procedure to that described in preparation 1 (step <BR> <BR> <BR> <BR> 2). mp 115-116 oC ; IR (KBr) 3329, 1693, 1504cm-1; 1H NMR (CDCl3)# # 2.30 (s, 3H, CH3), 7.12 (d, J = 8.4 Hz, 1H), 7.28 (s, 1H), 8.20 (d, J = 8.4 Hz, 1H), 10.48 (brs, 1H, NH) ; Mass (m/z) 214 (M+.).

Step 3 2-Nitro-5-(morpholin-1-yl)aniline (12.0 g, 78 %) was prepared by the above acetamide (15.0 g, 0.07 mol) (obtained in step 2 above), morpholine (34.0 g, 0.35 mol), potassium hydroxide (5.88 g, 0.105 mol) and dimethyl sulfoxide (100 mL) by an analogous procedure to that described in preparation 1 (step 3). mp 159 - 160 °C; IR (KBr) 3334,1236cm-1; 1H NMR (CDCl3) 6 3.30 (t, J = 5.0 Hz, 4H, N(CH2)2), 3.80 (t, J = 5.2 Hz, 4H, N(CH2)2), 5.96 (s, 1H), 6.12 (brs, 2H, NH2), 6.30 (d, J = 7.5 Hz, 1H), 8.08 (d, J = 8.8 Hz, 1H) ; Mass (m/z) 223 (M+.).

Step 4 The nitroaniline derivative (8.9 g, 0.04 mol) (obtained in step 3 above) was hydrogenated using 10 % Pd-C (2.5 g) in ethanol (40 mL), by an analogous procedure to that described in preparation 1 (step 4) to yield 3-(morpholin-1-yl)-1,2-phenylenediamine (6.0 g, 78 %) as a brown viscous oil.

IR (Neat) 3372cm-1; 1H NMR (CDCl3) 63.08 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.24 (brs, 4H, 2 x NH2), 3.84 (t, J = 4.8 Hz, 4H, O(CH2)2), 6.30 (d, J = 8.6 Hz, 1H), 6.38 (s, 1H), 6.68 (d, J = 8.4 Hz, 1H) ; Mass (m/z) 193 (M+.).

Step 5 5-(Morpholin-1-yl)-2-mercapto-1H-benzimidazole (5.5 g, 76 %) was prepared by an analogous procedure to that described in preparation 1 (step 5) using the diamine (6.0 g, 0.031 mol) (obtained in step 4 above), carbon disulfide (2.83 g, 0.037 mol), potassium hydroxide (2.08 g, 0.037 mol), ethanol (40 mL) and water (10 mL). mp 270 oC (decomp.); IR (KBr) 3353, 1414 cm-1; 1H NMR (DMSO-d6) 6 2. 45 (s, 1H, SH), 2.92 (t, J=4.2 Hz, 4H, N(CH2)2), 3.70 (t, J = 4.4 Hz, 4H, O(CH2)2), 6.46 (d, J = 8.2 Hz, 1H), 6.70 (s, 1H), 6.80 (d, J = 8.3 Hz, 1H); Mass (m/z) 235 (M+.).

Preparation 14 5-(4-Methylpiperazin-1-yl)-2-mercapto-1H-benzimidazole: Step 1 5-(4-Methylpiperazin-1-yl)-2-nitroaniline (15.0 g, 93 %) was prepared from (5-chloro-2- nitrophenyl)acetamide (15.0 g, 0.07 mol) (obtained in preparation 13, step 2), 4-methyl piperazine (35.0 g, 0.35 mol), potassium hydroxide (5.88 g, 0. 105 mol) and dimethyl sulfoxide (100 mL), by an analogous procedure to that described in preparation 1 (step 3). mp 109-110 oC ; IR (KBr) 3445, 1249 cm-1; 1H NMR (CDCl3) 6 2.36 (s, 3H, CH3), 2.52 (t, J = 5.0 Hz, 4H, N(CH2)2), 3.38 (t, J = 5.1 Hz, 4H, N(CH2)2), 5.98 (s, 1H), 6.12 (brs, 2H, NH2), 6.30 (d, J = 7.2 Hz, 1H), 8.02 (d, J = 8.2 Hz, 1H) ; Mass (m/z) 236 (M+.).

Step 2 The nitroaniline derivative (15.0 g, 0.063 mol) (obtained in step 1 above) was hydrogenated using 10 % Pd-C (2.5 g) in ethanol (60 mL) by an analogous procedure to that described in preparation 1 (step 4) to yield 3-(4-methylpiperazin-1-yl)-1,2-phenylene diamine (12.0 g, 92 %) as a brown viscous oil. IR (Neat) 3331 cm-1; 1H NMR (DMSO-d6) 6 2.40 (s, 3H, CH3), 2.64 (t, J = 5.4 Hz, 4H, N(CH2)2), 3.10 (t, J = 5.3 Hz, 4H, N(CH2)2), 3.40 (brs, 4H, 2 x NH2), 6.40 (s, 1H), 6.68 (d, J = 8.1 Hz, 1H), 6.80 (d, J = 7.8 Hz, 1H) ; Mass (m/z) 206 (M+.).

Step 3 5-(4-Methylpiperazin-1-yl)-2-mercapto-1H-benzimidazole (11.0 g, 77 %) was prepared by an analogous procedure to that described in preparation 1 (step 5) using the diamine (12.0 g, 0.058 mol) (obtained in step 2 above), carbon disulfide (5.2 g, 0.069 mol), potassium hydroxide (3.8

g, 0.069 mol), ethanol (50 mL) and water (10 mL). mp 280 oC (decomp.) ; IR (KBr) 3080, 1480 cm-1; 1H NMR (CD30D + CDCl3) 6 2.10 (s, lH, SH), 2.40 (s, 3H, CH3), 2.65 (t, J = 4.2 Hz, 4H, N(CH2)2), 3.18 (t, J = 4.5 Hz, 4H, N(CH2)2), 6.82 (s, 1H), 6.90 (d, J = 8.2 Hz, 1H), 7.12 (d, J = 8.7 Hz, 1H), 7.56 (brs, 1H, NH); Mass (m/z) 248 (M+.).

Preparation 15 5-[4-t-butyloxycarbonylpiperazin-1-yl)-2-merapto-1H-benzimid azole : Step 1 5-(Piperazin-1-yl)-2-nitroaniline (10.0 g, 91 %) was prepared from (5-chloro-2-nitrophenyl) acetamide (10.7 g, 0.05 mol) (obtained in preparation 13, step 2), piperazine (43.0 g, 0.5 mol), potassium hydroxide (4.2 g, 0.075 mol) and dimethyl sulfoxide (50 mL), by an analogous procedure to that described in preparation 1 (step 3). mp 159 - 160 OC; IR (KBr) 3314, 1624 cm- <BR> <BR> <BR> 1; 1H NMR (CD3OD) # 2.90 (t, J = 5.2 Hz, 4H, N(CH2)2), 3.32 (t, J=5.1 Hz, 4H, N(CH2)2), 4.80 (brs, 3H, NH), 6.14 (s, 1H), 6.34 (d, J = 9.2 Hz, 1H), 7.90 (d, J = 9.6 Hz, 1H); Mass (m/z) 222 (M+.).

Step 2 The nitroaniline derivative (10.0 g, 0.045 mol) (obtained in step 1 above) was hydrogenated using 10 % Pd-C (1.5 g) in ethanol (45 mL), by an analogous procedure to that described in preparation 1 (step 4) to yield 4-(piperazin-1-yl)-1,2-phenylenediamine (8.0 g, 93 %) as a brown viscous oil.

IR (Neat) 3342 cm-1; 1H NMR (CDCl3) 6 2.80 (brs, 5H, NH), 3.00 (m, 8H, 4 x NCH2), 6.30 (d, J = 8.2 Hz, 1H), 6.38 (s, 1H), 6.62 (d, J = 8.0 Hz, 1H); Mass (m/z) 192 (M+.).

Step 3

5-(Piperazin-1-yl)-2-mercapto-lH-benzimidazole (7.9 g, 85 %) was prepared by an analogous procedure to that described in preparation 1 (step 5) using the diamine (8.0 g, 0.04 mol) (obtained in step 2 above), carbon disulfide (3.6 g, 0.048 mol), ethanol (40 mL) and water (4 mL). mp 260 - 261 OC ; IR (KBr) 3350, 1498 cm-1; 1H NMR (DMSO-d6) 6 2.40 (s, 1H, SH), 3.00 (t, J = 4.4 Hz, 4H, N(CH2)2), 3.50 (brs, 1H, NH), 4.42 (t, J = 4.5 Hz, 4H, N(CH2)2), 6.68 (s, 1H), 6.85 (d, J = 8.0 Hz, 1H), 7.03 (d, J = 8.4 Hz, 1H) ; Mass (m/z) 234 (M+.).

Step 4 5-(4=t-Butyloxyhcarbonylpiperazin-1-yl)-2-mercapto-1H-benzim idazole (2.6 g, 52 %) was prepared by an analogous procedure to that described in preparation 5 (step 4) using the benzimidazole (3.5 g, 0.015 mol) (obtained in step 3 above), di-t-butyldicarbonate (4.0 g, 0.018 mol), 1N NaOH solution (18 mL, 0.018 mol) and dioxane (10 mL). mp 219 - 220 OC ; IR (KBr) 3093, 1698, 1477 cm-1; IHNMR (DMSO-d6) 6 1.42 (s, 9H, 3 x CH3), 2.26 (s, 1H, SH), 3.00 (m, 4H, N(CH2)2), 3.48 (m, 4H, N(CH2)2), 6.68 (s, 1H), 6.88 (d, J = 8.8 Hz, 1H), 7.16 (d, J = 8.6 Hz, 1H), 12.40 (brs, 1H, NH); Mass (m/z) 334 (M+.).

Preparation 16 5-(Piperidin-1-yl)-2-mercapto-1H-benzimidazole: Step 1 5-(Piperidin-1-yl)-2-nitroaniline (14.8 g, 72%) was prepared from (5-chloro-2-nitro phenyl)acetamide (20.0 g, 0.093 mol) (obtained in preparation 13, step 2), piperidine (10.8 g, 0.24 mol), potassium hydroxide (3.9 g, 0.07 mol) and dimethyl sulfoxide (40 mL), by an analogous procedure to that described in preparation 1 (step 3). mp 100 - 101 ecC; IR (KBr) 3461, 1239 cm H 1H NMR (CDCl3) 5d 1.56 (m, 2H, CH2), 1.68 (m, 4H, (CH2) 2), 3.40 (m, 4H, N(CH2)2) 5.90 (s,

(s, 1H), 6.10 (brs, 2H, NH2), 6.28 (d, J = 8.2 Hz, 1H), 8.02 (d, J = 8.0 Hz, 1H); Mass (m/z) 221 (M+.).

Step 2 The nitroaniline derivative (17.0 g, 0.076 mol) (obtained in step 1 above) was hydrogenated using 10% Pd-C (4.0 g) in ethanol (75 mL) by an analogous procedure to that described in preparation 1 (step 4) to yield 4-(piperidin-1-yl)-1 ,2-phenylenediamine (13.8 g, 97%) as a viscous oil. IR (Neat) 3390, 1252 cm-1; 1H NMR (CDC3) #d 1.52 (m, 2H, CH2), 1.70 (t, J=4.7 Hz, 4H, (CH2)2), 2.90 (t, J = 5.0 Hz, 4H, N(CH2)2), 3.00 (brs, 4H, 2 x NH2), 6.32 (d, J = 8.3 Hz, 1H), 6.38 (s, 1H), 6.62 (d, J = 8.1 Hz, 1H); Mass (m/z) 191 (M+.).

Step 3 <BR> <BR> <BR> 5-(Piperaidin-1-yl)-2-mercapto-1H-benzimidazole (1 (10.0 g, 56%) was prepared by an analogous procedure to that described in preparation 1 (step 5) using the diamine (15.0 g, 0.078 mol) (obtained in step 2 above), carbon disulfide (7.16 g, 0.94 mol), potassium hydroxide (5.27 g, <BR> <BR> <BR> 0.094 mol), ethanol (70 mL) and water (10 mL); IR (KBr) 3125, 1497 em 1; 1H NMR (DMSO-d6) 3d 1.50 (m, 2H, CH2), 1.60 (t, J = 4.2 Hz, 4H, (CH2) 2), 3.02 (t, J = 4.5 Hz, 4H, N(CH2)2), 6.66 (s, 1H), 6.72 (d, J = 8.4 Hz, 1H), 7.00 (d, J = 8.4 Hz, 1H); Mass (m/z) 233 (M+.).

Preparation 17 5-(Hexampethyleneimin-1-yl)-2-mercapto-1H-benzimidazole: Step 1 5-(Hexamethyleneimin-1-yl)-2-nitroaniline (1.8 g, 33%) was prepared from (5-chloro-2- nitrophenyl)acetamide (5.0 g, 0.023 mol) (obtained in preparation 13, step 2), hexamethyleneimine (11.5 g, 0. 12 mol), potassium hydroxide (1.95 g, 0.033 mol) and dimethyl

sulfoxide (10 mL) using an analogous procedure to that described in preparation 1 (step 3). mp 97-98#°C; IR (KBr) 3460, 1253 cm-1; 1H NMR (CDCl3) # 1.56 (m, 4H, (CH2)2), 1.82 (m, 4H, (CH2) 2), 3.48 (t, J = 6.2 Hz, 4H, N(CH2)2), 5.74 (s, 1H), 6.14 (d, J = 7.1 Hz, 1H), 6.10 (brs, 2H, NH2), 7.98 (d, J = 9.6 Hz, 1H); Mass (m/z) 235 (M+.).

Step 2 The nitroaniline derivative (1.8 g, 0.0076 mol) (obtained in step 1 above) was reduced using stannous chloride dihydrate (5.2 g, 0.023 mol) and Conc. HCl (20 mL) by an analogous procedure to that described in preparation 10 (step 2) to yield 4-(hexamethyleneimin-1-yl)-1,2- phenylenediamine (1.4 g, 90%) as a viscous oil. IR (Neat) 3364, 1257 cm-1, 1H NMR (CDCl3) #d 1.52 (m, 4H, (CH2)2), 1.78 (m, 4H, (CH2) 2), 3.37 (t, J = 6.0 Hz, 4H, N(CH2)2), 3.56 (brs, 4H, 2 x NH2), 6.08 (d, J = 8.4 Hz, 1H), 6.12 (s, 1H), 6.64 (d, J = 7.4 Hz, 1H); Mass (m/z) 205 (M+.).

Step 3 5-(Hexamethyleneimin-1-yl)-2-mercapto-lH-benzimidazole (1.65 g, 98%) was prepared by an analogous procedure to that described in preparation 1 (step 5) using the diamine (1.4 g, 0.0068 mol) (obtained in step 2 above), carbon disulfide (1.03 g, 0.013 mol), potassium hydroxide (0.76 g, 0.013 mol), ethanol (10 mL) and water (2 mL). mp 275 - 276 eeC; IR (KBr) 3092, 1498 cm-1, H NMR (CDCl3 + DMSO-d6) #d 1.52 (m, 4H, (CH2)2), 1.90 (m, 4H, (CH2)2), 3.46 (t, J = 6.3 Hz, 4H, N(CH2)2), 6.44 (s, 1H), 6.50 (d, J = 8.9 Hz, 1H), 6.93 (d, J = 8.8 Hz, 1H), 11.50 (brs, 1H, NH); Mass (m/z) 247 (M+.).

Preparation 18 4,6-Difluoro-5-(morpholin-1-yl)-2-mercapto- 111-benzimidazole:

Step 1 2,3,4-Trifluoroaniline (36.7 g, 0.25 mol) was acetylated using acetic anhydride (105 mL, 1.25 mol), using an analogous procedure to that described in preparation 1 (step 1) to yield N-(2,3,4- trifluorophenyl)acetamide (39.0 g, 83 %) as a white solid. mp 87 - 88 OC ; IR (KBr) 3271, 1673, 1514 cm-1; 1H NMR (CDCl3) 6 2.16 (s, 3H, CH3), 6.90 (q, J = 4.3 Hz, 1H), 7.60 (brs, 1H, NH), 7.90 (m, 1H); Mass (m/z) 189 (M+.).

Step 2 N-(2,3,4-Trifluoro-6-nitrophenyl)acetamide (38.0 g, 82 %) was prepared from the acetamide (37.8 g, 0.2 mmol) (obtained in step 1 above), conc. HNO3 (33 mL), conc H2SO4 (42 mL), by an analogous procedure to that described in preparation 1 (step 2). mp 96 - 97 OC ; IR (KBr) 3265, 1683, 1502cm-1; 1H NMR (CDCl3) 6 2.30 (s, 3H, CH3), 7.82 (t, J = 4.6 Hz, 1H), 8.24 (brs, 1H, NH); Mass (m/z) 234 (M+.).

Step 3 2,4-Difluoro-3-(morpholin-1-yl)-6-nitroaniline (19.2 g, 74 %) was prepared from the acetamide (23.0 g, 0.1 mol) (obtained in step 2 above), morpholine (43.5 g, 0.5 mol), potassium hydroxide (8.4 g, 0.15 mol) and dimethyl sulfoxide (100 mL), using an analogous procedure to that described in preparation 1 (step 3). mp 77 - 78 OC; IR (KBr) 3315, 1489 cm~ 1H NMR (CDCl3) 8 3.40 (t, J = 4.2 Hz, 4H, N(CH2)2), 3.86 (t, J = 4.6 Hz, 4H, O(CH2)2), 6.00 (brs, 2H, NH2), 7.68 (d, J = 13.2 Hz, 1H); Mass (m/z) 259 (M+.).

Step 4 The nitroaniline derivative (9.1 g, 0.035 mol) (obtained in step 3 above) was hydrogenated using 10 % Pd-C (1.5 g) in ethanol (40 mL), by an analogous procedure to that described in preparation 1(stop 4) to yield 4,6-difluoro-5-(morpholin-1-yl)-1,2-phenylenediamine (7.8 g, 97 %) as a brown viscous oil, which was directly converted to 4,6-difluoro-5-(morpholin-1-yl)-2-mercapto-1H- benzimidazole (6.6 g, 70 %), following an analogous procedure to that described in preparation 1(step 5) using carbon disulfide (3.2 g, 0.042 mol), potassium hydroxide (2.3 g, 0.042 mol) ethanol (30 mL) and water (10 mL). mp 119-120 OC ; IR (KBr) 3072,1476cm-i; 1H NMR

(DMSO-d6) 6 3.06 (t, J = 4.4 Hz, 4H, N(CH2)2), 3.68 (t, J = 4.6 Hz, 4H, O(CH2)2), 6.84 (d, J = 12.8 Hz, 1H); Mass (m/z) 271 (M+.).

Preparation 19 4,6-Difluoro-5-(4-methylpiperazin-1 -yl)-2-mercapto-1 H-benzimidazole: Step 1 2,4-Difluoro-3-(4-melthylpiperazin-1-yl)-6-nitroaniline (12.0 g, 70%) was prepared from (2,3,4- trifluoro-6-nitro)acetamide (15.0 g, 0.064 mol) (obtained in preparation 18, step 2), 4- methylpiperazine (32.0 g, 0.032 mol), potassium hydroxide (5.4 g, 0.097 mol) and dimethyl sulfoxide (50 mL), by an analogous procedure to that described in preparation 1 (step 3). IR (Neat) 3475, 1249 cm-1, 1H NMR (CDCl3) 6 2.32 (s, 3H, CH3), 2.54 (m, 4H, N(CH2)2), 3.30 (m, 4H, N(CH2)2), 6.08 (brs, 2H, NH2), 7.64 (d, J = 13.8 Hz, 1H); Mass (m/z) 272 (M+.).

Step 2 The nitroaniline derivative (10.0 g, 0.036 mol) (obtained in step 1 above) was hydrogenated using 10% Pd-C (2.0 g) in ethanol (40 mL), following an analogous procedure to that described in preparation 1 (step 4) to yield 4,6-difluoro-5-(4-methylpiperazin- 1 -yl)- 1 ,2-phenylenediamine (8.8 g, 98.7%) as a brown viscous oil, which was directly converted to 4,6-difluoro-5-(4- methylpiperazine-1-yl)-2-mercapto-1H-bezimidazole (6.7 g, 65%) by an analogous procedure to that described in preparation 1 (step 5) using carbon disulfide (5.5 g, 0.072 mol), potassium hydroxide (2.5 g, 0.043 mmol), ethanol (70 mL) and water (10 mL). mp 280 - 281 eeC ; IR (KBr) 3085, 1475 cm-1; 1H NMR (DMSO-d6) #d 2.22 (s, 3H, NCH3), 2.44 (m, 4H, N(CH2)2), 3.02 (m, 4H, N(CH2)2), 6.86 (d, J = 12.8 Hz, 1H), 12.90 (brs, 1H, NH); Mass (m/z) 284 (M+.).

Preparation of Pyridinylmethylthio benzimidazole derivatives General Procedure : 2-Mercapto-lH-benzimidazole derivative (1.0 eq) (obtained in preparation 1 - 19) and sodium hydroxide (2.0 eq) were dissolved in ethanol (1.0 mL /1.0 mmol) and stirred for 0.5 to 1 h at ca 30 "C. To the resulting solution was added 2-chloromethylpyridine hydrochloride derivative (1.0 to 1.1 eq) (prepared by known methods,J Med. Chem. 1992, 35, 1049-1057, US Patent No.

5 045 552). The mixture was stirred for 6 to 12 h at ca 60 OC. After the reaction is complete, (monitored by TLC) the reaction mixture was filtered to remove insoluble salts and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography using a mixture of methanol and ethyl acetate (1 : 9 to 1 : 1) as eluent to afford the title compound.

Following compounds (Examples 1 to 42) were prepared according to the general procedure described above Example 1 2-[[4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluoro -5-(imidazol1-1-yl)-1H- benzimidazole: The title compound (2.8 g, 74 %) was prepared by the general procedure using 6-fluoro-5- (imidazol-1-yl)-2-mercapto-lH-benzimidazole (2.4 g, 10.0 mmol) (obtained in preparation 1), 4-methoxy-3,5-dimethyl-2-chloromethylpyridine hydrochloride (2.4 g, 11.0 mmol), sodium hydroxide (0.8 g, 20.0 mmol) and ethanol (30 mL). mp 186-187 °C ; IR (KBr) 3100, 1399cm'; lH NMR (CDCl3+CD30D) bd 2.28 (s, 3H, CH3), 2.40 (s, 3H, CH3), 3.86 (s, 3H, OCH3), 4.68 (s,

2H, SCH2), 7.20 (s, 1H), 7.40 (d, J = 4.0 Hz, 1H), 7.48 (s, 1H), 7.60 (d, J = 5.8 Hz, 1H), 7.90 (s, 1H), 8.20 (s, 1H); Mass (m/z) 383 (M+.).

Example 2 2-[[3-Melthyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylth io]-6-fluoro-5-(imidazol-1-yl)- lH-benzimidazole : The title compound (2.7 g, 60 %) was prepared by the general procedure using 6-fluoro-5- (imidazol-1lyl)-2-mercapto-1H-benzimidazole (2.4 g, 10.0 mmol) (obtained in preparation 1), 3- methyl-4-(2,2,2-trifluoroethoxy-2-chloromethylpyridine hydrochloride (3.0 g, 11.0 mmol), sodium hydroxide (0.8 g, 20.0 mmol) and ethanol (20 mL). mp 197-198 °C ; IR (KBr) 3436, 1255, 1112 cm-1; 1H NMR (DMSO-d6) #d 2.28 9s, 2H, CH3), 4.78 (s, 2H, SCH2), 4.98 (q, J=5.9 Hz, 2H, OCH2CF3), 7.00 (d, J = 6.0 Hz, 1H), 7.08 (s, 1H), 7.52 (s, 1H), 7.60 (d, J = 6.0 Hz, 1H), 7.68 (d, J = 4.2 Hz, 1H), 8.00 (s, 1H), 8.30 (d, J = 5.7 Hz, 1H), 13.15 (brs, 1H, NH); Mass (m/z) 437 (M+.).

Example 3 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methylthio]-6-fluoro-5-(imidazol-1-yl)-1H- benzimidazole:

The title compound (0.5 g, 62 %) was prepared by the general procedure using 6-fluoro-5- (imidazol-l -yl)-2-mercapto-l H-benzimidazole (0.41 g, 2.0 mmol) (obtained in preparation 1), 4-methoxy-3 -methyl-2-chloromethylpyridine hydrochloride (0.5 g, 2.0 mmol), sodium hydroxide (0.16 g, 4.0 mmol) and ethanol (20 mL0. mp 214-215°C; IR (KBr) 3101, 1582, 1437 mc01; H NMR (CDCl3+CD30D) 5 2.30 (s, 3H, CH3), 3.90 (s, 3H, OCH3), 4.60 (s, 2H, SCH2), 6.88 (d, J = 5.7 Hz, lH), 7.20 (s, lH), 7.32 (s, lH), 7.42 (d, J 7.6 Hz, lH), 7.56 (d, J=6.1 Hz, 1H), 7.82 (s, 1H), 8.30 (d, J = 6.1 Hz, 1H); Mass (m/z) 369 (M+.).

Example 4 2-[ [(4-(3-MelthoxyPropoxy)-3-methyl)pyridin-2-yl] methylthio] -6-fluoro-5-(imidazol-1 -yl)- 1H-benzimidazole: The title compound (0.46 g, 64 %) was prepared by the general procedure using 6-fluoro-5- (imidazol-l -yl)-2-mercapto-l H-benzimidazole (0.40 g, 1.7 mmol) (obtained in preparation 1), 4-(3-methoxypropoxy)-3-methyl-2-chloromethylpyridine hydrochloride (0.45 g, 1.7 mmol),

sodium hydroxide (0.14 g, 3.4 mmol) and ethanol (20 mL). IR (KBr) 3435, 1582, 1428 cm4; H NMR (CDCl3) 2.18 (m, 2H, CH2), 2.30 (s, 3H, CH3), 3.40 (s, 3H, OCH3), 3.60 (t, J = 5.7 Hz, 2H, OCH2), 4.20 (t, J = 5.9 Hz, 2H, OCH2), 4.40 (s, 2H, SCH2), 6.80 (d, J = 6.1 Hz, 1H), 7.20 (s, 1H), 7.26 (s, 1H), 7.40 (d, J = 7.8 Hz, 1H), 7.46 (d, J = 10.2 Hz, 1H), 7.80 (s, 1H), 8.38 (d, J = 5.9 Hz, 1H), 13.80 (brs, 1H, NH); Mass (m/z) 427 (M+.).

Example 5 2-i [(4-Methoxy)pyridin-2-yl] methylthioj -6-fluoro-5-(imidazol-1-yl)-1H-benzimidazole: The title compound (1.9 g, 60 %) was prepared by the general procedure using 6-fluoro-5- (imidazol-1-yl)-2-mercapto-1H-benzimidazole (2.1 g, 9.0 mmol), (obtained in preparation 1) 4- methoxy-2-chloromethylpyridine hydrochloride (1.74 g, 9.0 mmol), sodium hydroxide (0.72 g, 18.0 mmol) and ethanol (15 mL). mp 86 - 87 cC; IR (KBr) 3430, 1600 cm-1; H NMR (CDCl3) 5 3.90 (s, 3H, OCH3), 4.38 (s, 2H, SCH2), 6.92 (d, J = 5.7 Hz, 1H), 6.96 (s, 1H), 7.30 (m, 2H), 7.42 (d, J = 10.2 Hz, 1H), 7.58 (d, J = 7.8 Hz, 1H), 7.80 (s, 1H), 8.50 (d, J = 6.0 Hz, 1H), 14.00 (brs, 1H, NH); Mass (m/z) 355 (M+.).

Example 6 2-[ [(4-Chloro-3-methyl)pyridin-2-yl] methylthio]-6-fluoro-5-(imidazol-1-yl)-1H- benzimidazole;

The title compound (0.72 g, 70 %) was prepared by the general procedure using 6-fluoro-5- (imidazol-1-yl)-2-mercapto-1H-benzimidazole (0.65 g, 2.75 mmol) (obtained in preparation 1), 4-chloro-3-methyl-2-chloromethylpyridine hydrochloride (0.58 g, 2.75 mmol), sodium hydroxide (0.22 g, 5.5 mmol) and ethanol (25 mL). mp 131 - 132 °C; IR (KBr) 3392, 1502, 1437 cm-1; 1H <BR> <BR> NMR (CDCl3) 6 2.60 (s, 3H, CH3), 4. 60 (s, 2H, SCH2), 7.26 (d, J = 5.6 Hz, 1H), 7.28 (s, 1H), 7.36 (s, 1H), 7.42 (d, J = 10.3 Hz, 1H), 7.58 (d, J = 7.8 Hz, 1H), 7.88 (s, 1H), 8.40 (d, J = 5.9 Hz, 1H), 13.00 (brs, 1H, NH); Mass (m/z) 373 (M+).

Example 7 2-[ [(4-Methoxy-3,5-dimethyl)pyridin-2-yl] methylthio]-6-fluoro-5-(morpholin-1-yl)-1H- benzimidazole: The title compound (2.6 g, 65 %) was prepared by the general procedure using 6-fluoro-5- (morpholin-1-yl)-2-mercapto-1H-benzimideazole (2.55 g, 10.0 mmol) (obtained in preparation 2), 4-methoxy-3,5-dimethyl-2-chloromethylpyridine hydrochloride (2.0 g, 11.0 mmol), sodium hydroxide (0.8 g, 20.0 mmol) and ethanol (20 mL). mp 176 - 177 °C ; IR (KBr) 3427, 1476, 1428

cm-1; 1H NMR (DMSO-d6) # 2.20 (s, 3H, CH3), 2.28 (s, 3II, CH3), 3.38 (t, J = 4.2 Hz, 4H, N(CH2)2), 3.70 (s, 3H, OCH3), 3.78 (t, J = 4.4 Hz, 4H, O(CH2)2), 4.64 (s, 2H, SCH2), 7.20 (d, J = 8.2 Hz, 1H), 7.38 (d, J = 10.3 Hz, 1H), 8.20 (s, 1H), 12.60 (brs, 1H, NH); Mass (m/z) 402 (M+.).

Example 8 2-[ [3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl] methylthio] -6-fluoro-5-(morpholin-1-yl)- 1H-benzimidazole: The title compound (2.1 g, 58 %) was prepared by the general procedure using 6-fluoro-5- (morpholin-1-yl)-2-mercpato-1H-bezimidzole (2.0 g, 8.0 mmol) (obtained in preparation 2), 3-methyl-4-(2,2,2-trifluoroethoxy)-2-chloromethylpyridine hydrochloride (2.2 g, 8.0 mmol), sodium hydroxide (0.64 g, 16.0 mmol) and ethanol (20 mL). mp 205 - 206 °C ; IR (KBr) 3340, <BR> <BR> <BR> 1584, 1269 cm'; ; HNMR (CD3OD) # 2.28 (s, 3H, CH3), 3.08 (t, J = 4.0 hz, 4H, N(CH2)2), 3.90 (t, J = 4.5 Hz, 4H, O(CH2)2), 4.60 (s, 2H, SCH2), 4.70 (q, J = 6.1 Hz, 2H, OCH2CF3), 7.00 (d, J = 5.9 Hz, 1H0, 7.12 (d, J = 8.2 Hz, 1H), 7.20 (d, J = 12.4 Hz, 1H), 8.26 (d, J = 5.7 Hz, 1H); Mass (m/z) 456 (M+.).

Example 9 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (mjorpholin-1-yl)-1H- benzimidzaole:

The title compound (0.58 g, 75 %) was prepared by the general procedure using 6-fluoro-5- (morpholin-1-yl)-2-mercapto-1H- benzimdazole (0.51 g, 2.0 mmol) (obtained in preparation 2), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.42 g, 2.0 mmol), sodium hydroxide (0.16 g, 4.0 mmol) and ethanol (10 mL). mp 106-107 °C; IR (KBr) 3340, 1582, 1428 Cm0-1; 61H NMR (CDCl3) # 2.30 (s, 3H, CH3), 3.10 (t, J=4.6 Hz, 4H, N(CH2)2), 3.90 (m, 7H, OCH + O(CH2)2), 4.38 (s, 2H SCH2), 6.80 (d, J = 5.6 Hz, 1H), 7.10 (d, J = 7.8 Hz, 1H), 7.26 (d, J = 10.2 Hz, 1H), 8.36 (d, J = 6.0 Hz, 1H); Mass (m/z) 388 (M+.).

Example 10 2-[ [(4-(3-Melthoxypropoxy)-3-methyl)pyridin-2-yl] methylthio]-6-fluoro-5-(morpholin-1-yl)- 1H-benzimidazole: The title compound (0.22 g, 62 %) was prepared by the general procedure using 6-fluoro-5- (morphoiin-l -yl)-2-mercapto-l H-benzimidazole (0.19 g, 0.76 mmol) (obtained in preparation 2), 4-(3-methoxypropoxy)-3-methyl-2-chloromethylpyridine hydrochloride (0.2 g, 0.76 mmol), sodium hydroxide (0.06 g, 1.52 mmol) and ethanol (5 mL). IR (KBr) 3431, 1584, 1428 cm-1; 1H

NMR (CDCl3) 8 2.10 (m, 2H, CH2), 2.28 (s, 3H, CH3), 3.08 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.38 (s, 3H, OCH3), 3.60 (t, J = 5.6 Hz, 2H, OCH2), 3.90 (t, J = 4.8 Hz, 4H, (OCH2)2), 4.18 (t, J = 6.0 Hz, 2H, OCH2), 4.38 (s, 2H, SCH2), 6.80 (d, J = 5.7 Hz, 1H), 7.10 (d, J = 7.8 Hz, 1H), 7.26 (d, J = 10.4 Hz, 1H), 8.38 (d, J = 5.6 Hz, 1H); Mass (m/z) 446 (M+.).

Example 11 2-[[(4-Morpholin-1-yl)-3-methylpyridin-2-yl]methylthio]-6-fl uoro-5-(morpholin-1-yl)-1H- benzimidazole: The title compound (0.4 g, 25 %) was prepared by the general procedure using 6-fluoro-5- (morphoin-1-yl)-2-mercapto-1H-benzimidazole (0.9 g, 3.6 mmol) (obtained in preparation 2), 4-(morpholin-l -yl)-3-methyl-2-chloromethyipyridine hydrochloride (1.06 g, 3.9 mmol), sodium hydroxide (0.36 g, 9.1 mmol) and ethanol (10 mL). mp 102 - 103 °C ; IR (KBr) 3440, 1471 cm-'; 'H NMR (CDCl3) 3 2.34 (s, 3H, CH3), 3.02 (t, J = 4.6 Hz, 4H, N(CH2)2, 3.08 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.90 (m, 8H, 2 x O(CH2)2), 4.36 (s, 2H, SCH2), 6.86 (d, J = 5.6 Hz, 1H), 7.12 (d, J = 7.2 Hz, 1H), 7.24 (d, J = 10.3 Hz, 1H), 8.40 (d, J = 5.6 Hz, 1H); Mass (m/z) 443 (M+).

Example 12 2-[[(4-Piperidin-1-yl)-3-methylpyridin-2-yl]methylthio]-6-fl uoro-5-(morpholin-1-yl)-1H- benzimidazole:

The title compound (2.7 g, 50 %) was prepared by the general procedure using 6-fluoro-5- (morpholin-1-yl)-2-mercapto-1H-bezimidazole (0.30 g, 1.2 mmol) (obtained in preparation 2), 4-(piperidin-1-yl)-3-methyl-2-chloroomethylpyridine hydrochloride (0.31 g, 1.2 mmol), sodium hydroxide (0.10 g, 2.4 mmol) and ethanol (10 mL). mp 289 - 290 °C ; IR (KBr) 3429, 1580, 1474 cm-'; lH NMR (CDCl3) 6 1.50 - 1.84 (m, 6H, (CH2) 3), 2.30 (s, 3H, CH3), 2.98 (t, J = 5.4 Hz, 4H, N(CH2)2), 3.08 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.92 (t, J = 4.5 Hz, 4H, O(CH2)2), 4.32 (s, 2H, SCH2), 6.82 (d, J = 5.5 Hz, 1H), 7.12 (d, J = 7.4 Hz, 1H), 7.26 (d, J = 12.0 Hz, 1H), 8.30 (d, J = 5.7 Hz, 1H); Mass (m/z) 441 (M+.).

Example 13 2-[[(4-(4-Melthylpiperazin-1-yl)-3-methylpyridin-2-yl]methyl thio]-6-fluoro-5-(morpholin-1- yl)-1H-benzimidazole:

The title compound (0.5 g, 27 %) was prepared by the general procedure using 6-fluoro-5- (morpholin-1-yl)-2-mercapto-1H-benzimidazole (1.02 g, 4.0 mmol) (obtained in preparation 2), 4-(4-methylpiperazin-1-yl)-3-methyl-2-chloromethylpyridine hydrochloride (1.1 g, 4.0 mmol), sodium hydroxide (0.24 g, 8.0 mmol) and ethanol (10 mL). mp 289 - 290 cC; IR (KBr) 3440, 1581, 1429 cm'; 'H NMR (CDCl3) 6 2.30 (s, 3H, CH3), 2.40 (s, 3H, CH3), 2.60 (m, 4H, N(CH2)2), 3.00 (m, 8H, 2 x (CH2)2), 3.90 (t, J = 4.5 Hz, 4H, O(CH2)2), 4.32 (s, 2H, SCH2), 6.84 (d, J = 5.6 Hz, 1H), 7.10 (d, J = 7.6 Hz, 1H), 7.22 (d, J = 11. 2 Hz, 1H), 8.32 (d, J = 5.7 Hz, 1H); Mass (m/z) 456 (M+.).

Example 14 2-[[(3-Methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (morpholin-1-yl)-1-H-benzimidazole:

The title compound (0.1 g, 71 %) was prepared by the general procedure using 6-fluoro-5- (morpholin-l -yl)-2-mercapto-l H-benzimidazole (0.1 g, 0.4 mmol) (obtained in preparation 2), 3-methyl-2-chloromethylpyridine hydrochloride (0.07 g, 0.4 mmol), sodium hydroxide (0.05 g, 1.2 mmol) and ethanol (5 mL). IR (KBr) 2972, 1428 cm'; 'H NMR (CDCl2) 6 2.42 (s, 3H, CH3), 3.08 (t, J = 4.4 Hz, 4H, N(CH2)2), 3.90 (t, J = 4.4 Hz, 4H, O(CH2)2), 4.36 (s, 2H, SCH2), 7.10 (d, J = 7.4 Hz, lH), 7.20 - 7.28 (m, 2H), 7.60 (d, J = 7.5 Hz, lH), 8.48 (d, J = 5.6 Hz, 1H); Mass (m/z) 358 (M+.).

Example 15 2-! [(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluoro-5 -(piperidin-1-yl)-1H benzimidazole: The title compound (0.48 g, 60 %) was prepared by the general procedure using 6-fluoro-5- (piperidin-1-yl~-2mercapto-1H-benzimidazole (0.5 g, 2.0 mmol) (obtained in preparation 3), 4- methoxy-3,5-dimethyl-2-chloromethylpyridine hydrochloride (0.37 g, 2.0 mmol), sodium hydroxide (0. 16 g, 4.0 mmol) and ethanol (10 mL). mp 100-101 °C ; IR (KBr) 3100, 1475, 1427 cm-1; H NMR (CDCl3) 6 1.60 (m, 2H, CH2), 1.80 (m, 4H, (CH2) 2), 2.30 (s, 3H, CH3), 2.38 (s, 3H, CH3), 3.00 (t, J = 5.4 Hz, 4H, N(CH2)2), 3.82 (s, 3H, OCH3), 4.34 (s, 2H, SCH2), 7.12 (d, J = 6.9 Hz, 1H), 7.22 (d, J = 12.0 Hz, 1H), 8.30 (s, 1H); Mass (m/z) 400 (M+.).

Example 16 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)~pyridin-2-yl] methylthio] -6-fluoro-5-(piperidin-1 -yl)- 1H-benzimidazole:

The title compound (0.45 g, 50 %) was prepared by the general procedure using 6-fluoro-5- (piperidin-1-yl)-2-mercapto-lH-benzimidazole (0.5 g, 2.0 mmol) (obtained in preparation 3), 3- methyl-4-(2,2,2,-trifluoroethoxy)-2-chloromethylpyridine hydrochloride (0.47 g, 2.0 mmol), sodium hydroxide (0.16 g, 4.0 mmol) and ethanol (10 mL). mp 160-161 OC; IR (KBr) 3122, 1585, 1432 cm-1; 1H NMR (CDCl3) 8 1.60 (m, 2H,CH2), 1.80 (m, 4H, (CH2) 2), 2.38 (s, 3H, CH3) 3.00 (m, 4H, N(CH2)2), 4.40 (s, 2H, SCH2), 4.46 (q, J = 7.8 Hz, 2H, OCH2CF3), 6.74 (d, J = 5.5 Hz, 1H), 7.18 (d, J = 7.6 Hz, 1H), 7.26 (d, J = 10.0 Hz, 1H), 8.42 (d, J = 5.5 Hz, 1H), 12.50 (s, 1H, NH) ; Mass (m/z) 454 (M+).

Example 17 2-[[(4-methoxuy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5 -(piperidin-1-yl)-1H- benzimidazole : The title compound (0.5 g, 65 %) was prepared by the general procedure using 6-fluoro-5- (piperidin-1-yl)-2-mercapto-lH-benzimidazole (0.5 g, 2.0 mmol) (obtained in preparation 3), 4- methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.4 g, 2.0 mmol), sodium hydroxide

(0.16 g, 4.0 mmol) and ethanol(l0 mL). mp 170-171 OC ; IR (KBr) 3131, 1582, 1170 cm-1; 1H NMR (CDCl3) # 1.60 (m, 2H, CH2), 1.80 (m, 4H, (CH2)2), 2.26 (s, 3H, CH3), 3.00 (m, 4H, N(CH2)2), 3.94 (s, 3H, OCH3), 4.40 (s, 2H, SCH2), 6.80 (d, J = 5.4 Hz, 1H), 7.18 (d, J = 7.2 Hz, 1H), 7.24 (d, J = 10.6 Hz, 1H), 8.40 (d, J = 5.6 Hz, 1H); Mass (m/z) 386 (M+).

Example 18 2-! [(4-Piperidin-1-yl)-3-methylpyridin-2-yl] methylthio]-6-fluoro-5-(piperidin-1-yl)-1H- benzimidazole: The title compound (0.95 g, 63 %) was prepared by the general procedure using 6-fluoro-5- (piperidin-1-yl)-2-mercapto-lH-benzimidazole (0.70 g, 2.8 mmol) (obtained in preparation 3), 4-(piperidin-1-yl)-3-methyl-2-chloromethylpyridine hydrochloride (0.91 g, 3.5 mmol), sodium hydroxide (0.30 g, 7.7 mmol) and ethoanol (15 mL). mp 161 - 162 °C ; IR (KBr) 3430, 1581, 1429 cm-1; 1H NMR (CDCl3) 6 1.60 (m, 4H, 2 x CH2), 1.74 (m, 8H, 2 x (CH2)2), 2.30 (s, 3H, CH3), 3.00 (m, 8H, 2 xN(CH2)2), 4.32 (s, 2H, SCH2), 6.82 (d, J = 5.4 Hz, 1H), 7.12 (d, J = 7.7 Hz, 1H), 7.24 (d, J = 12.1 Hz, 1H), 8.28 (d, J = 5.5 Hz, 1H); Mass (m/z) 439 (M+).

Example 19 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluor o-5-(4-methylpiperazin-1-yl)- 1H-benzimidazole:

The title compound (1.8 g, 60 %) was prepared by the general procedure using 6-fluoro-5-(4- methylpiperazin-1-yl)-2-mercapto-lH-benzimidazole (2.0 g, 7.5 mmol) (obtained in preparation 4), 4-methoxy-3,5-dimethyl-2-chloromethylpyridine hydrochloride (1.52 g, 8.2 mmol), sodium hydroxide (0.6 g, 15.0 mmol) and ethanol (30 mL). mp 120-121 OC ; IR (KBr) 3390, 1475, 1427 cm-1; 1H NMR (CDCl3) 6 2.30 (s, 3H, CH3), 2.32 (s, 3H CH3), 2.70 (s, 3H, CH3), 3.10 (m, 4H, N(CH2)2), 3.36 (m, 4H, N(CH2)2), 3. 80 (s, 3H, OCH3) 4.34 (s, 2H, SCH2), 7.12 (d, J = 7.5 Hz, 1H), 7.22 (d, J = 8.4 Hz, 1H), 8.32 (s, 1H); Mass (m/z) 415 (M+).

Example 20 2- [[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl] methylthio]-6-fluoro-5-(4- metholpiperazin-1-yl)1H-benzimidazole : The title compound (1.48 g, 64 %) was prepared by the general procedure using 6-fluoro-5-(4- methylpiperazin-l -yl)-2-mercapto-l H-benzimidazole (1.33 g, 5.0 mmol) (obtained in preparation 4), 3-methyl-4-(2,2,2-trifluoroethoxy)-2-chloromethylpyridine hydrochloride (1.5 g, 5.5 mmol), sodium hydroxide (0.4 g, 10.0 mmol) and ethanol (25 mL). mp 109-110 OC; IR (KBr) 3397,

1584, 1258 cm-1; 1H NMR (DMSO-d6) 6 2.38 (s, 3H, CH3), 2.80 (s, 3H, CH3), 3.12 (m, 4H, N(CH2)2), 3.40 (m, 4H, N(CH2)2), 4.48 (q, J = 7.9 Hz, 2H, OCH2CF3), 4.60 (s, 2H, SCH2), 6.80 (d, J = 5.8 Hz, 1H), 7.14 (d, J = 7.1 Hz, 1H), 7.24 (d, J = 11.7 Hz, 1H), 8.40 (d, J = 5.5 Hz, 1H); Mass (m/z) 469 (M+).

Example 21 2! (4-Methoxy-3-methyl)pyridin-2-yl] methylthio]-6-fluoro-5-(4-methylpiperazin-1-yl)-1H- benzimidazole: The title compound (2.5 g, 78 %) was prepared by the general procedure using 6-fluoro-5-(4- methylpiperzin-1-yl)-2-mercapto-1H-benzimidazole (2.12 g, 8.0 mmol) (obtained in preparation 4), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (1.6 g, 8.0 mmol), sodium hydroxide (0.64 g, 16.0 mmol) and ethanol (30 mL). mp 118 - 120 OC ; IR (KBr) 3432, 1585, <BR> <BR> <BR> 1296 cm-1; 1H NMR (DMSO-d6) # 2.20 (s, 3H, CH3), 2.38 (s, 3H, CH3), 2.60 (m, 4H, N(CH2)2), 3.00 (m, 4H, N(CH2)2), 3.86 (s, 3H, OCH3), 4.68 (s, 2H, SCH2), 6.98 (d, J = 5.6 Hz, 1H), 7.12 (d, J = 7.1 Hz, 1H), 7.28 (d, J = 11. 2 Hz, 1H), 8.30 (d, J = 5.8 Hz, 1H), 12.76 (brs, 1H, NH); Mass (m/z) 401 (M+).

Example 22 2- pyridin-2-yl] methylthio]-6-fluoro-5-(4-methylpiperazin-1-yl)-1H- benzimidazole:

The title compound (0.6 g, 22 %) was prepared by the general procedure using 6-fluoro-5-(4- methylpiperazin-1-yl)-2-mercapto-lH-benzimidazole (2.0 g, 7.5 mmol) (obtained in preparation 4), 3-methyl-2-chloromethylpyridine hydrochloride (1.0 g, 7.5 mmol), sodium hydroxide (0.36 g, 9.0 mmol) and ethanol (15 mL). IR (Neat) 3150, 1429 cm-1; 1H NMR (CDCl3) 6 2.42 (s, 3H, CH3), 2.50 (s, 3H, CH3), 2.90 (m, 4H, N(CH2)2), 3. 20 (m, 4H, N(CH2)2), 4.38 (s, 2H, SCH2), 7.12 (d, J = 7.6 Hz, 1H), 7.20 - 7.26 (m, 2H), 7.58 (d, J = 7.4 Hz, 1H), 8.46 (d, J = 4.6 Hz, 1H); Mass (m/z) 371 (M+.).

Example 23 2-[ [(4-Methoxy-3,5-dimethyl)pyridin-2-yl] methylthio]-6-fluoro-5-(4-t-butyloxycarboyl piperazin-1 -yl)-1H-benzimidazole: The title compound (1.5 g, 52 %) was prepared by the general procedure using 6-fluoro-5-(4-t- butyloxycarbonylpiperazin-1-yl)-2-mercapto-1H-benzimidazole (2.0 g, 5.7 mmol) (obtained in preparation 5), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (1.0 g, 5.7 mmol), sodium hydroxide (0.34 g, 8.52 mmol) and ethanol (20 mL). mp 147 - 148 OC; IR (KBr) 3066, 1696, 1462 cm-1; 1H NMR (CDC13) 6 1.50 (s, 9H, 3 x CH3), 2.28 (s, 3H, CH3), 2.34 (s, 3H, CH3), 3.00 (m, 4H, N(CH2)2), 3.60 (m, 4H, N(CH2)2), 3. 80 (s, 3H, OCH3), 4.38 (s, 2H, SCH2), 7. 10 (d, J = 7.6 Hz, 1H), 7.22 (d, J = 1.0 Hz, 1H), 8.24 (s, 1H); Mass (m/z) 501 (M+).

Example 24 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methlthio]-6-fluoro-5-( 4-t-butyloxycarbonylipiperazin- 1-yl)-1H-benzimidazole: The title compound (0.65 g, 66 %) was prepared by the general procedure using 6-fluoro-5-(4- t-butyloxycarbonylpiperazin- 1-yl)-2-mercapto-l H-benzimidazole (0.70 g, 2.0 mmol) (obtained in preparation 5), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.42 g, 2.0 mmol), sodium hydroxide (0.16 g, 4.0 mmol) and ethanol (10 mL). mp 84 - 85 OC; IR (KBr) 3431, 1684, 1427 cm-1; 1H NMR (CDCl3) 6 1.50 (s, 9H, 3 x CH3), 2.26 (s, 3H, CH3), 3.00 (m, 4H, N(CH2)2), 3.68 (m, 4H, N(CH2)2), 3.90 (s, 3H, OCH3), 4.40 (s, 2H, SCH2), 6.78 (d, J = 5.6 Hz, 1H), 7.10 (d, J = 7.3 Hz, 1H), 7.24 (d, J = 10.8 Hz, 1H), 8.40 (d, J = 5.7 Hz, 1H); Mass (m/z) 487 (M+).

Example 25 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylthio-6-fluoro-5-( 4-(ethylenethioxy)piperidin- 1 -yl)-1H-benzimidazole : The title compound (1.3 g, 46 %) was prepared by the general procedure using 6-fluoro-5-(4- ethylenedioxy)piperidin-1-yl)-2-mercapto-1H-benzimidazole (2.0 g, 6.4 mmol) (obtained in preparation 6), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (1.2 g, 6.6 mmol), sodium hydroxide (0.78 g, 8.4 mmol) and ethanol (20 mL). mp 70 - 71 CC; IR (KBr) 3416, 1582, 1097 cm-1 ; 1H NMR (CDCl3) 6 1.92 (t, J = 5.4 Hz, 4H, (CH2) 2), 2.24 (s, 3H, CH3), 3.16 (t, J = 5.2 Hz, 4H, N(CH2)2), 3.92 (s, 3H, OCH3), 4.02 (s, 4H, O(CH2)2O), 4.32 (s, 2H, SCH2), 6.76 (d, J = 5.8 Hz, 1H), 7.04 (d, J = 6.8 Hz, 1H), 7.22 (d, J = 10.8 Hz, 1H), 8.36 (d, J = 5.8 Hz, 1H), 12.50 (brs, 1H, NH); Mass (m/z) 444 (M+).

Example 26 2-[ [(4-Methoxy-3-methyi)pyridin-2-yl] methylthio]-6-fluoro-5-(4-(piperid-1-yl)-1H- benzimidazole):

A mixture of 2- [[(4-methoxy-3 -methyl)pyridin-2 -ylj methylthioj -6-fluoro- 5 -(4- cthylenedioxy)piperidin-1-yl)-1H-benzimidazole (0.7 g, 1.8 mmol) (obtained in Example 25), 6N HCl (20 mL) and acetone (25 mL) was refluxed for 12 h. The acetone was removed under reduced pressure and the residue was dissolved in ethyl acetate. The organic phase was washed with saturated NaHCO3 solution, brine and dried over Na2SO4 and concentrated under reduced pressure to afford the title compound (0.3 g, 50 %). mp 128 - 129 °C ; IR (KBr) 3337, 1710, 1433 cm-1; 1H NMR (CDC13) 6 2.28 (s, 3H, CH3), 2.66 (t, J = 5.8 Hz, 4H, (CH2)2), 3.38 (t, J = 5.8 Hz, 4H, N(CH2)2), 3.90 (s, 3H, OCH3), 4.34 (s, 2H, SCH2), 6.78 (d, J = 5.8 Hz, 1H), 7.12 (d, J = 7.8 Hz, 1H), 7.24 (d, J = 11.4 Hz, 1H), 8.36 (d, J = 5.8 Hz, 1H), 13.00 (brs, 1H, NH); Mass (m/z) 400 (M+).

Example 27 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methyltho]-6-fluoro-5-( 4-(hydroxyimino)piperidin- 1-yl)-1H-benzimidazole: The title compound (1.0 g, 84 %) was prepared by the general procedure using 6-fluoro-5-(4- (hydroxyimino)piperidin-1-yl)-2-mercapto-1H-benzimidazole (0.8 g, 2.8 mmol) (obtained in preparation 8), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.6 g, 2.8 mmol), sodium hydroxide (0.23 g, 5.6 mmol) and ethanol (10 mL). mp 210 - 211 OC ; IR (KBr) 3450, 3052, 1582, 1478 cm 1H NMR (DMSO-d6) 6 2.22 (s, 3H, CH3), 2.44 (t, J = 5.4 Hz, 2H, CH2), 2.68 (t, J = 5.4 Hz, 2H, CH2), 3.08 (t, J = 6.2 Hz, 4H, N(CH2)2), 3.88 (s, 3H, OCH3), 4.68 (s, 2H, SCH2), 6.98 (d, J = 6.6 Hz, 1H), 7.22 (d, J = 7.8 Hz, 1H), 7.26 (d, J = 9.3 Hz, 1H), 8.28 (d, J = 6.6 Hz, 1H), 10.44, (s, 1H, OH), 12.60 (s, 1H, NH); Mass (m/z) 415 (M+).

Example 28

2-[ [(4-Methoxy-3 -methyl)pyridin-2-yl] methylthio]-6-fluoro-5-[4-(hydroxy)piperidin-1- -ylj - 1H-benzimidazole: The title cmopound (1.5 g, 83 %) was prepared by the general procedure using 6-fluoro-5-(4- hydroxypiperidin-1-yl)-2-mercapto-1H-benzimidazole (1.28 g, 4.17 mmol) (obtained in preparation 9), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.88 g, 4.17 mmol), soldium hydroxide (0.4 g, 10.4 mmol) and ethoanol (30 mL). mp 116-117°C; IR (KBr) 3450, 3156, 1075cm-1; 1H NMR (CDCl3) 61.68 - 1.72 (m, 2H, CH2), 1.92-2.08 (m, 2H, CH2), 2.22 (s, 3H, CH3), 2.80 (t, J = 5.7 Hz, 2H, NCH2), 3.24 (t, J = 5.6 Hz, 2H, NCH2), 3.88 (s, 3H, OCH3), 3.80 - 3.92 (m, 2H, CHOH), 4.32 (s, 2H, SCH2), 6.72 (d, J = 5.8 Hz, 1H), 7.08 (d, J 7.2 Hz, 1H), 7.20 (d, J = 12.0 Hz, 1H), 8.32 (d, J = 5.8 Hz, 1H), 13.00 (brs, 1H, NH); Mass (m/z) 402 (M+).

Example 29 2-[ [(4-Methoxy-3-melthyl)pyridin-2-yl]methylthio]-6-fluoro-5-(h examethyleneimin-1-yl)- 1H-benzimidazole:

The title compound (0.5 g, 41 %) was prepared by the general procedure using 6-fluoro-5- (hezamethyleneimin-1-yl)-2-mercapt-1H-benzimidazole (0.82 g, 3.1 mmol) (obtained in preparation 10), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.58 g, 3.4 mmol), sodium hydroxide (0.25 g, 6.2 mmol) and ethanol (15 mL). mp 73-74 °C ; IR (KBr) 3075, 1582, 1478 cm-1 ; 1H NMR (CDCl3) 6 1.67 (m, 4H, (CH2)2), 1.86 (m, 4H, (CH2)2), 2.26 (m, 3H, CH3), 3.30 (t, J = 5.8 Hz, 4H, N(CH2)2), 3.92 (s, 3H, OCH3), 4.34 (s, 2H, SCH2), 6.78 (d, J = 5.8 Hz, 1H), 7.04 (d, J = 9.9 Hz, 1H), 7.20 (d, J = 12.8 Hz, 1H), 8.38 (d, J = 5.7 Hz, 1H); Mass (m/z) 400 (M+).

Example 30 2-[[(4-Morpholin-1-yl)-3-methyl)pyridin-2-yl]metylthio]-6-fl uro-5-(hexamethyleneimin- 1-yl)-1H-benzimidazole: The title compound (0.47 g, 27 %) was prepared by the general procedure using 6-fluoro-5- (hexamethyleneimin-1-yl)-2-mercapto-lH-benzimidazole (1.0 g, 3.77 mmol) (obtained in preparation 10), 4-(morpholin-1-yl)-3-methyl-2-chloromethylpyridine hydrochloride (0.99 g, 3.77 mmol), sodium hydroxide (0.3 g, 7.54 mmol) and ethanol (10 mL). mp 141-142 °C ; IR (KBr) 3438, 1579 cm-1; 1HNMR (CDCl3) 6 1.68 (m, 4H, (CH2)2), 1.82 (m, 4H, (CH2)2), 2.32 (s, 3H, CH3), 2.98 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.28 (t, J = 5.0 Hz, 4H, N(CH2)2), 3.88 (t, J = 4.2 Hz, 4H, O(CH2)2), 4.34 (s, 2H, SCH2), 6.84 (d, J = 5.6 Hz, 1H), 7.02 (d, J = 7.8 Hz, 1H), 7.18 (d, J = 12. 9 Hz, 1H), 8.36 (d, J = 5.5 Hz, 1H); Mass (m/z) 455 (M+).

Example 31 2-[[4-(Methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5- (2 (methoxymelthyl)pyrroldidn-1-yl)-1H-beziimidazole: The title compound (1.1 g, 68 %) was prepared by the general procedure using 6-fluoro-5-(2- (methoxymethyl)pyrrolidin-1-yl)-2-mercapto-1H-benzimidazole (1.0 g, 3.55 mmol) (obtained in preparation 11), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.67 g, 3.9 mmol), sodium hydroxide (0.28 g, 7.11 mmol) and ethanol (10 mL). IR (Neat) 2930, 1582, 1477 cm-1; 1HNMR(CDCl3) 6 1.90 - 2.04 (m, 4H, (CH2)2), 2.26 (s, 3H, CH3), 3.10 - 3.24 (m, 2H, NCH2), 3.30 (s, 3H, OCH3), 3.48-3.70 (m, 2H, OCH2), 3.92 (s, 3H, OCH3), 4.00 - 4.10 (m, 1H, CH), 4.36 (s, 2H, SCH2), 6.78 (d, J = 6.6 Hz, 1H), 6.98 (d, J = 7.6 Hz, 1H), 7.24 (d, J = 13.1 Hz, 1H), 8.38 (d, J = 5.9 Hz, 1H); Mass (m/z) 416 (M+).

Example 32 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methylthio]-6-fluoro-5-(pyrrolidin-1-yl)-1H- benzimidazole:

The title compound (0.85 g, 54 %) was prepared by the general procedure using 6-fluoro-5- (pyrrolidin-l -yl)-2-mercapto-l H-benzimidazole (0.95 g, 4.2 mmol) (obtained in preparation 12), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.81 g, 4.2 mmol), sodium hydroxide (0.34 g, 8.4 mmol) and ethanol (10 mL). mp 120 - 121 °C ; IR (Neat) 3145, 1582, 1433 cm ; 1H NMR (CDCl3) 6 1.96 (m, 4H, (CH2) 2), 2.24 (s, 3H, CH3), 3.32 (m, 4H, N(CH2)2), 3.88 (s, 3H, OCH3), 4.36 (s, 2H, SCH2), 6.76 (d, J = 5.6 Hz, 1H), 6.84 (d, J = 7.8 Hz, 1H), 7.20 (d, J = 13.1 Hz, 1H), 8.34 (d, J = 5.8 Hz, 1H); Mass (m/z) 372 (M+).

Example 33 2-[[(4-melthoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-5-(mor pholin-1-yl)-1H- benzimidazole: The title compound (1.05 g, 66 %) was prepared by the general procedure using 5-(morpholin-1 - yl)-2-mercapto- 1 H-benzimidazole (1.0 g, 4.2 mmol) (obtained in preparation 13), 4-methoxy- 3,5-dimethyl-2-chloromethylpyridine hydrochloride (0.9 g, 4.2 mmol), sodium hydroxide (0.34 g, 8.4 mmol) and ethanol (10 mL). IR (KBr) 3427, 1446, 1288 cm-1; 1H NMR (CDCl3) 6 2.28 (s, 3H, CH3), 2.32 (s, 3H, CH3), 3.14 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.80 (s, 3H, OCH3), 3.88 (t, J = 4.8 Hz, 4H, O(CH2)2), 4.38 (s, 2H, SCH2), 6.90 (d, J = 6.7 Hz, 1H), 7.08 (s, 1H), 7.46 (d, J = 8.8 Hz, 1H), 8.24 (s, 1H), 10.8 (brs, 1H, NH); Mass (m/z) 384 (M+).

Example 34 2-! [3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl] methylthio]-5-(morpholin-1-yl)-1H- benzimidazole:

The title compound (1.05 g, 61 %) was prepared by the general procedure using 5-(morpholin-1 - yl)-2-mercapto-lH-benzimidazole (1.0 g, 4.2 mmol) (obtained in preparation 13), 3-methyl-4- (2,2,2-trifluoroethoxy)-2-chloromethylpyridine hydrochloride (1.15 g 4.2 mmol), sodium hydroxide (0.34 g, 8.4 mmol) and ethanol (10 mL). IR (Neat) 3432, 1582, 1282 cm-1; 1H NMR (CDCl3) 6 2.30 (s, 3H, CH3), 3.14 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.90 (t, J = 4.8 Hz, 4H, O(CH2)2), 4.42 (q, J = 4.6 Hz, 2H, OCH2CF3), 4.48 (s, 2H, SCH2), 6.70 (d, J = 5.9 Hz, 1H), 6.90 (d, J = 6.7 Hz, 1H), 7.08 (s, 1H), 7.48 (d, J = 8.7 Hz, 1H), 8.40 (d, J = 5.8 Hz, 1H), 8.50 (brs, 1H, NH) ; Mass (m/z) 438 (M+).

Example 35 2-[[(4-Methyox-3-methyl)pyridin-2-yl]methylthio]-5-(morpholi n-1-yl)-1H-benizmidazole The title compound (1.0 g, 55 %) was prepared by the general procedure using 5-(morpholin-1- yl)-2-mercapto-lH-benzimidazole (1.2 g, 5.0 mmol) (obtained in preparation 13), 4-methoxy-3- methyl-2-chloromethylpyridine hydrochloride (1.0 g, 5.0 mmol), sodium hydroxide (0.4 g, 10.0 mmol) and ethanol (30 mL). mp 60-61 OC ; IR (KBr) 3150, 1581, 1295 cm-1 ; 1H NMR

(CDCl3) 3 2.18 (s, 3H, CH3), 3.12 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.86 (t, J = 4.6 Hz, 4H, O(CH2)2), 3.90 (s, 3H, OCH3), 4.54 (s, 2H, SCH2), 6.92 (d, J = 5.8 Hz, 1H), 6.98 (d, J = 8.9 Hz, 1H), 7.02 (s, 1H), 7.40 (d, J = 9.2 Hz, 1H), 8.20 (d, J = 5.8 Hz, 1H) ; Mass (m/z) 370 (M+).

Example 36 2-[ [(4-Methoxy-3,5-dim ethyi)pyridin-2-yl] methylthio]-5-(4-melthylpiperazin-1-yl)-1H- benzimidazole: The title compound (1.4 g, 60 %) was prepared by the general procedure using 5-[4- methylpiperazin-1-yl)2-2mercapto-1H-benzimidazole (1.5 g, 6.0 mmol) (obtained in preparation 14), 4-methoxy-3,5-dimethyl-2-chloromethylpyridine hydrochloride (1.0 g, 6.0 mmol), sodium hydroxide (0.48 g, 12.0 mmol) and ethanol (30 mL). IR (Neat) 3404, 1446 cm-1; 1H NMR (CDCl3) 6 2.30 (s, 3H, CH3), 2.38 (s, 3H, CH3), 2.52 (s, 3H, NCH3), 2.90 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.32 (t, J = 5.0 Hz, 4H, N(CH2)2), 3.80 (s, 3H, OCH3), 4.34 (s, 2H SCH2), 6.90 (d, J = 6.7 Hz, 1H), 7.08 (s, 1H), 7.44 (d, J = 8.7 Hz, 1H), 8,30 (s, 1H). Mass (m/z) 397 (M+).

Example 37 2-[ [(4-Methoxy-3-methyl)pyridin-2-yll methylthio]-5-(4-methylpiperazin-1-yl)1H- benzimidazole:

The title compound (0.96 g, 64 %) was prepared by the general procedure using 5-(4- methylpiperazin-l -yl)-2-mercapto-l H-benzimidazole (0.99 g, 4.0 mmol) (obtained in preparation 14), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.83 g, 4.0 mmol), sodium hydroxide (0.32 g, 8.0 mmol) and ethanol (20 mL). mp 134 - 135 °C; IR (KBr) 3440, 1441 cm- 1; lH NMR (DMSO-d6)# 2.20 (s, 3H, CH3), 2.24 (s, 3H, CH3), 2.52 (t J 5.4 Hz, 4H, N(CH2)2), 3.08 (t, J = 5.6 Hz, 4H, N(CH2)2), 3.84 (s, 3H, OCH3), 4.60 (s, 2H, SCH2), 6.82 (d, J = 6.2 Hz, 1H), 6.90 (s, 1H), 7.00 (d, J = 7.6 Hz, 1H), 7.40 (d, J = 8.9 Hz, 1H), 8.24 (d, J = 5.9 Hz, 1H), 12.60 (brs, 1H, NH); Mass (m/z) 383 (M+).

Example 38 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] metholthio]-5-(4-t-butyloxycarbonylpiperazin-1-yl)- 1 H-benzimidazole: The title compound (0.93 g, 66 %) was prepared by the general procedure using 5-[4-t- butyloxycarbonylpiperazin- 1-yl)-2-mercapto-l H-benzimidazole (1.0 g, 3.0 mmol) (obtained in preparation 15), 4-methoxy-3 -methyl-2-chloromethylpyridine hydrochloride (0.74 g, 3.5 mmol), sodium hydroxide (0.24 g, 6.0 mmol) and ethanol (30 mL). mp 180 - 181 °C; ; IR (KBr) 3247, 1694,1421cm-1; 1H NMR (CD3OD)# 1.50 (s, 9H, 3x CH3), 2.16 (s, 3H, CH3). 3.10 (t, J=4.8 Hz, 4H, N(CH2)2), 3.60 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.90 (s, 3H, OCH3), 4.36 (s, 2H, SCH2), 6.76 (d, J = 5.6 Hz, 1H), 6.98 (d, J = 6.8 Hz, 1H), 7.04 (s, 1H), 7.42 (d, J = 8.7 Hz, 1H), 8.36 (d, J = 5.8 Hz, 1H); Mass (m/z) 469 (M+).

Example 39 2-[ (4-Methoxy-3-methyl)pyridin-2-yI] methylthio] -5-(piperidin-1 yl)-1H-benzimidazole:

The title compound (2.2 g, 62 %) was prepared by the general procedure using 5-(piperidin-1- yl)-2-mercapto-1H-benzimidazole (2.5 g, 10.0 mmol) (obtained in preparation 16), 4-methoxy-3- methyl-2-chloromethylpyridine hydrochloride (2.4 g, 11.0 mnl), sodium hydroxide (0.8 g, 20.0 mmol) and ethanol (30 mL). mp 210 - 211 °C ; IR (KBr) 3340, 1581, 1479 cm' ; 1H NMR (CDCl3) 6 1.56 (m, 2H, CH2), 1.74 (m, 4H, (CH2)2), 2.22 (s, 3H, CH3), 3.10 (t, J = 5.4 Hz, 4H, N(CH2)2), 3.86 (s, 3H, OCH3), 4.36 (s, 2H, SCH2), 6.72 (d, J = 5.9 Hz, 1H), 6.96 (d, J = 11.2 Hz, 1H), 7.10 (s, 1H), 7.44 (d, J = 9.8 Hz, 1H), 8.36 (d, J = 5.8 Hz, 1H); Mass (m/z) 368 (M+).

Example 40 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methylthio]-5-(hexamethyleneinimin-1-yl)-1H- benzimidazole: The title compound (0.9 g, 39 %) was prepared by the general procedure using 5- (hexamethyleneimin- 1-yl)-2-mercapto-l H-benzimidazole (1.5 g, 6.1 mmol) (obtained in preparation 17), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (1.3 g, 6.1 mmol), sodium hydroxide (0.48 g, 12.2 mmol) and ethanol (20 mL). mp 151 - 152 °C ; IR (KBr) 3338, 1528, 1452cm-1; IHNMR (CDCl3) 6 1.54 (m, 4H, (CH2)2), 1.82 (m, 4H, (CH2)2), 2.24 (s, 3H,

CH3), 3.50 (t, J = 5.8 Hz, 4H, N(CH2)2), 3.88 (s, 3H, OCH3), 4.34 (s, 2H, SCH2), 6.66 (d, J = 11.2Hz, lH), 6.72 (d, J = 5.4 Hz, 1H), 6.76 (s, 1H), 7.36 (d, J = 9.1 Hz, 1H), 8.36 (d, J = 5.8 Hz, 1H); Mass (m/z) 382 (M+).

Example 41 <BR> <BR> <BR> 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methyithio] -4,6-difluoro-5-(morpholin-l-yl)-1H- benzimidazole: The title compound (1.1 g, 73 %) was prepared by the general procedure using 4,6-difluoro-5- (morpholin-1-yl)-2-mercapto-1H-benzimidazole (1.0 g, 3.7 mmol) (obtained in preparation 18), 4-methoxy-3-methyl-2-chloromethylpyridine hydrochloride (0.92 g, 4.4 mmol), sodium hydroxide (0.3 g, 7.4mmol) and ethanol (20 mL). mp 138 - 139 OC ; IR (KBr) 3268, 1438 cm-1; 1H NMR (CHCl3) # 2.28 (s, 3H, CH3), 3.20 (m, 4H, N(CH2)2), 3.84 (m, 4H, O(CH2)2), 3.90 (s, 3H, OCH3), 4.36 (s, 2H, SCH2), 6.78 (d, J = 4.8 Hz, 1H), 7.04 (d, J = 9.7 Hz, 1H), 8.34 (d, J = 5.7 Hz, 1H); Mass (m/z) 406 (M+).

Example 42 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-4,6-dif luoro-5-(4-methylpiperazin-1- yl-1H-benzimidazole:

The title compound (0.8 g, 87 %) was prepared by the general procedure using 4,6-difluoro-5-(4- methylpiperazin-l -yl)-2-mercapto-l H-benzimidazole (0.60 g, 2.1 mmol) (obtained in preparation 19), 4-methoxy-3,5-dimethyl-2-chloromethylpyridine hydrochloride (0.47 g, 2.5 mmol), sodium hydroxide (0.17 g, 4.2 mmol) and ethanol (10 mL). mp 176 - 177 OC ; IR (KBr) 3320, 1582, 1438 cm-1; 1H NMR (DMSO-d6) # 2.08 (s, 3H, CH3), 2.12 (s, 3H, CH3), 2.22 (s, 3H, CH3), 2.42 (m, 4H, N(CH2)2), 3.04 (m, 4H, N(CH2)2), 3.66 (s, 3H, OCH3), 4.62 (s, 2H, SCH2), 7.08 (d, J = 7. 6 Hz, 1Hz), 8.12 (s, 1H), 12.70 (brs, 1H,NH); Mass (m/z) 433 (M+.).

Preparation of Pyridylmethylsulfinyl benzimidazole derivatives and their sodium salts: General procedure: A solution of pyridylmethylthio benzimidazole derivative (1.0 eq) (see examples 1 - 42) in dichloromethane or chloroform (5.0 mL /1.0 mmol of substrate) was cooled to - 40 ° - 50 OC.

A solution of m-chloroperbenzoic acid (50 %, 0.9 to 1.5 eq) in dichloromethane or chloroform (1.0 mL /1.0 mmol of substrate) was cooled to -40 to - 50 oC and added dropwise to the above solution. The reaction mixture was stirred for 0.5 to 5 h at the same temperature and quenched with triethylamine (1.5 to 2.0 eq). The mixture was slowly warmed to - 10 OC, followed by the addition of an aqueous solution of sodium carbonate and stirred for 30 minutes. The mixture was extracted with chloroform and the extracts were washed with brine ; dried over anhydrous sodium sulfate and the solvent was removed under reduced pressure. The residue was purified by column chromatography over alumina using a mixture of methanol - ethyl acetate (1 : 9 to 4:1) as eluent. The syrupy oil was crystallised from diethyl ether or acetone to obtain the title compound.

To the compound obtained above (1.0 eq) was added 0. 1 N NaOH solution (1.0 eq) and stirred for 1 h at ca 30 oC. Ethanol was added and distilled to remove water as an azeotropic mixture with ethanol under reduced pressure. The residue obtained was crystallised from diethyl ether or acetone.

Following compounds (Examples 43 - 92) were prepared according to the general procedure described above.

Example 43

2-[[(4-Methox-3,5-dimethyl)pyridin-2-yl]melthylsulfinyl]-6-f luoro-5-(imidzol-1-yl)-1H- benzimidazole: The title compound (0.24 g, 46 %) was prepared according to the above general procedure using 2-[[(4-methoxy-3,5- dimethyl)pyridin-2-yl]methylthio]-6-fluoro-5-(imidazol-1-yl) -1H- benzimidazole (0.5 g, 1.3 mmol) (obtained in example 1), m-chloroperbenzoic acid (50 %, 0.54 g, 1.56 mmol) and chloroform (30 mL). mp 190-191 OC ; IR (KBr) 3440, 1044cm-i; 1HNMR (DMSO-d6) 6 2.20 (s, 6H, 2 x CH3), 3.80 (s, 3H, OCH3), 4.80 (s, 2H, SOCH2), 7.18 (s, 1H), 7.60 (s, 1H), 7.80 (d, J = 9.6 Hz, 1H), 7.90 (d, J = 7.8 Hz, 1H), 8.08 (s, 1H), 8.20 (s, 1H); Mass (m/z) 399 (M+.).

Example 44 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-f luoro-5-(imidazol-1-yl)-1H- benzimidazole, sodium salt The title compound (0.04 g, 95 %) was prepared by the above general procedure using 2-[[(4- methoxy-3,5-dimethyl)pyriddin-2-yl]methylsulfinyl]-6-fluoro- 5-(imidazol-1-yl)-1H- benzimidazole (0.04 g, 0.1 mmol) (obtained in example 43) and 0.1 N NaOH solution (1.0 mL,

0. 1 mmol). mp 239-240 OC; IR (KBr) 1440, 1040 cm-1; 1H NMR (CD30D) 6 2.12 (s, 3H, CH3), 2.30 (s, 3H, CH3), 3.70 (s, 3H, OCH3), 4.90 (s, 2H, SOCH2), 7.18 (s, 1H), 7.40 (s, 1H), 7.50 (d, J = 10.8 Hz, lH), 7.70 (d, J = 7.6 Hz, 1H), 7.90 (s, 1H), 8.20 (s, 1H).

Example 45 2-[[(4-Melthoxy-3,5-dimethyl)pyridin-2-yl]methylsulfonyl]-6- fluoro-5-(imdiazol-1-yl)-1H- benzimidazole: The title compound (0.22 g, 53 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 ,5-dimethyl)pyridin-2-yl]methylthio=]-6-fluoro-5-(imidazol- 1-yl)-1H-benzimidzole (0.38 g, 1.0 mmol) (obtained in example 1), m-chloroperbenzoic acid (50 %, 1.0 g, 3.0 mmol) and chloroform (20 mL). mp 160-161 OC ; IR (KBr) 3434, 1136 cm-1; 1H NMR (DMSO-d6) # 2.18 (s, 3H, CH3), 2.24 (s, 3H, CH3), 3.74 (s, 3H, OCH3), 5.38 (s, 2H, SO2CH2), 7.10 (s, 1H), 7.54 (s, 1H), 7.68 (d, J = 10.2 Hz, 1H), 7.86 (d, J = 7.6 Hz, 1H), 8.00 (s, 1H), 8.10 (s, 1H); Mass (m/z) 383 (M-32).

Example 46 2- [3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(imidazolp-1- yl)-1H-benzimidazole:

The title compound (0.24 g, 45 %) was prepared by the above general procedure using 2-[[3- methyl-4-(2, 2, 2-trilluoroethoxy) pyridin-2-yl] -6-fluoro-5-(imidazol-1-yl)-1 H- benzimidazole (0.5 g, 1.14 mmol) (obtained in example 2), m-chloroperbenzoic acid (50 %, 0.47 g, 1.4 mmol) and dichloromethane (10 mL). mp 234-235 OC ; IR (KBr) 3449, 1049cm-i; 1H NMR (CD30D+CDCl3) 6 2.28 (s, 3H, CH3), 4.42 (q, J = 6.3 Hz, 2H, OCH2CF3), 4.74 (ABq, J=9l6 Hz, #v=6.2 Hz, 2H, SOCH2), 6.74 (d,J=5.6 Hz, 1H), 7.20 (m, 2h), 7.52 (d, J=10.8 Hz, 1H), 7.70 (d, J = 7.6 Hz, 1H), 7.86 (s, 1H), 8.30 (d, J = 5.6 Hz, 1H); Mass (m/z) 453 (M+).

Example 47 2-[[3-Melthyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsu lfinyl]-6-fluoro-5-(imidazol-1- yl)-1H-benzimidazole, sodium salt: The title compound (0.04 g, 88 %) was prepared by the above general procedure using 2-[[3- methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methenylsulfiny l]-6-fluoro-5-(imidazol-l-yl)-1H- benzimidazole (0.045 g, 0.1 mmol) (obtained in example 46) and 0.1 N NaOH solution (1.0 mL, 0.1 mmol). mp 240-241 OC ; IR (KBr) 1466, 1040 cm-1; 1H NMR (DMSO-d6) 6 2. 22 (s, 3H, CH3), 4.60 (ABq, J = 10.4 Hz, Av = 54.0 Hz, 2H, SOCH2), 4.90 (q, J = 5.8 Hz, 2H, OCH2CF3), 7.08 (m, 2H), 7.40 (d, J = 8.2 Hz, 1H), 7.46 (s, 1H), 7.68 (d, J = 6.7 Hz, 1H), 7.90 (s, 1H), 8.38 (d, J = 5.4 Hz, 1H).

Example 48 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(imidazol-l-yl)-1H- benzimidazole:

The title compound (0.1 g, 64 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5-(imidaz ol-1-yl)-1H-bezimidzole (0.15 g, 0.4 mmol) (obtained in example 3), m-chloroperbenzoic acid (50 %, 0.17 g, 0.48 mmol) and dichloromethane (10 mL). mp 208-209 °Cl; IR (KBr) 3450, 1049 cm-1 1H NMR (CD3OD) # 2.14 (s, 3H, CH3), 3.88 (s, 3H, OCH3), 4.80 (s, 2H, SOCH2), 6.90 (d, J = 5.8 Hz, 1H), 7.12 (s, 1H), 7.44 (s, 1H), 7.60 (d, J = 10.3 Hz, 1H), 7.80 (d, J = 7.6 Hz, 1H), 8.98 (s, 1H), 8.10 (d, J = 5.7 Hz, 1H); Mass (m/z) 369 (m-16).

Example 49 2-[[(4-(3-Methoxyproopy)0-3-methyl)pyrindin-2-yl)methylsulfi nyl]-6-6fluoro-5-(imidazol-1- yl)-1-H~benzimidazole: The title compound (0.093 g, 55 %) was prepared by the above general procedure using 2-[[(4- (3 -methoxypropoxy)-3 -methol-pyridine-2-yl]methylthio]-6-fluoro-5-( -imidazol-1-yl)-1- H- benzimidazole (0. 15 g, 0.35 mmol) (obtained in example 4), m-chloroperbenzoic acid (50 %, 0.15 g, 0.42 mmol) and dichloromethane (20 mL). mp 150-151 OC ; IR (KBr) 3435, 1044 mc-1; 1H NMR (CDCl3) 6 2.10 (m, 2H, CH2), 2.24 (s, 3H, CH3), 3.38 (s, 3H, OCH3), 3.56 (t, J = 5.8

Hz, 2H, OCH2), 4.10 (t, J = 5.7 Hz, 2H, OCH2), 4.80 (ABq, J = 10.6 Hz, Av = 18.2 Hz, 2H, SOCH2), 6.74 (d, J = 6.1 Hz, 1H), 7.24 (m, 2H), 7.50 (d, J = 10.8 Hz, 1H), 7.68 (d, J = 7.6 Hz, 1H), 7.82 (s, 1H), 8.28 (d, J = 6.0 Hz, 1H); Mass (m/z) 427 (M -16) Example 50 2-! [(4-Methyoxy)pyridin-2-yl] methylsulfimyl]-6-fluoro-5-(imidazol-1-yl)-lH-benzimidazole The title compound (0.32 g, 58 %) was prepared by the above general procedure using 2-[[(4- methoxy)pyridin-2-yl]methylthio]-6-fluoro-5-(imidazol- 1 -yl)- 1 H-benzimidazole (0.53 g, 1.5 mmol) (obtained in example 5), m-chloroperbenzoic acid (50 %, 0.62 g, 1.8 mmol) and dichloromethane (20 mL). IR (KBr) 3500, 1048 cm-1; 1H NMR (CD30D) 6 3.86 (s, 3H, OCH3), 4.72 (ABq, J = 10.8 Hz, Av = 15.6 Hz, 2H, SOCH2), 6.94 (m, 2H), 7.22 (s, 1H), 7.52 (s, 1H), 7.68 (d, J = 10.8 Hz, 1H), 7.88 (d, J = 7.6 Hz, 1H), 8.08 (s, 1H), 8.26 (d, J = 5.6 Hz, 1H); Mass (m/z) 371 (M+.).

Example 51 2-[ [(4-Methyoxy)pyridin-2-yl] methylsulfinyl] -6-fluoro-5-(imidazol- 1-1-yl]- 1 H-benzimidazole, sodium salt:

The title compound (0.04 g, 78 %) was prepared by the above general procedure using 2-[[(4- methoxy)pyridin-2-yl]methylsulfinyl] -6-fluoro-5-(imidzol-l-yl)-1 H-benzimidazole (0.05 g, 0.13 mmol) (obtained in example 50) and 0.1 N NaOH solution (1.3 mL, 0.13 mmol). mp 142- 143 OC; IR (KBr) 1601, 1038 cm-1; 1H NMR (CD30D) 6 3.64, (s, 3H, OCH3), 4.90 (ABq, J 10.0 Hz, Av = 14.0 Hz, 2H, SOCH2), 6.60 (s, 1H), 6.89 (d, J = 5.6 Hz, 1H), 7.20 (s, 1H), 7.40 (s, 1H), 7.50 (d, J = 10.8 Hz, 1H), 7.70 (d, J = 7.6 Hz, lH), 7.98 (s, lH), 8.32 (d, J = 7.6 Hz, 1H).

Example 52 2-[ [(4-Chloro-3-methyl)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(imidazol-1-yl)-1H- benzimidazole: The title compound (0.3 g, 50 %) was prepared by the above general procedure using 2-[[(4- chloro-3-methyl)pyridin-2-yl]methylthio-6-fluoro-5-(imidazol - 1 -yl)- 1 H-benzimidazole (0.37 g, 1.0 mmol) (obtained in example 6), m-chloroperbenzoic acid (50 %, 0.4 g, 1.2 mmol) and dichloromethane (20 mL). mp 58 -60°C ; IR (KBr) 3429, 1044 cm-1; 1H NMR (CDC13) 82.40 (s, 3H, CH3), 4.88 (ABq, J = 10.2 Hz, Av = 19.6 Hz, 2H, SOCH2), 7.26 (m, 3H), 7.56 (d, J 8.2 Hz, 1H), 7.68 (d, J = 6.0 Hz, 1H), 7.90 (s, 1H), 8.20 (d, J = 5.8 Hz, 1H); Mass (m/z) 373 (M -16).

Example 53 2-[ [[(4-Methoxy-3,5-dimethyl)pyridin-2-yl] methylsulfinyl] -6-fluoro-5-(morpholin-1 -yl)-1H- benzimidzole:

The title compound (0.2 g, 40 %) was prepared by the above general procedure using 2-[[(4- methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluoro-5-(mo rpholin-1-yl)-1H-benzimidazole (0.5 g, 1.24 mmol) (obtained in example 7), m-chloroperbenzoic acid (50 %, 0.52 g, 1.5 mmol) and chloroform (20 mL). mp 179 - 180 OC ; IR (KBr) 3431, 1042 cm-1; 1 H NMR (CDCl3) 6 2.20 (s, 3H, CH3), 2.28 (s, 3H, CH3), 3.18 (m, 4H, N(CH2)2), 3.72 (s, 3H, OCH3), 3.98 (m, 4H, O(CH2)2), 4.78 (ABq, J = 10.0 Hz, Av = 8.0 Hz, 2H, SOCH2), 7.18 (d, J = 8.2 Hz, 1H), 7.26 (d, J = 10.6 Hz, 1H), 8.24 (s, 1H), 12.20 (brs, 1H, NH); Mass (m/z) 402 (M -16).

Example 54 2-[[(4-Methylxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6- fluoro-5-(morpholin-1-yl)-1H- benzimidazole, sodium salt: The title compound (0.04 g, 90 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 , 5 -dimethyl)pyridin-2-yl]methylsulfinyl]-6 -6-fluoro-5-(morpholin-1-yl)-1H- benzimidazole (0.04 g, 0.1 mmol) (obtained in example 53) and 0. 1 N NaOH solution (1.0 mL, 0.1 mmol). mp 184-185 OC ; IR (KBr) 1489, 1075 cm-i; 1H NMR (DMSO-d6) 6 2.22 (s, 6H, 2 x CH3), 3.00 (m, 4H, N(CH2)2), 3.72 (s, 3H, OCH3), 3.80 (m, 4H, O(CH2)2), 4.58 (ABq, J

= 10.6 Hz, Av = 54.0 Hz, 2H, SOCH2), 7. 10 (d, J = 7.6 Hz, 1H), 7.20 (d, J = 10.3 Hz, 1H), 8.25 (s, 1H).

Example 55 2-[ [3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl] methylsulfinyl] -6-fluoro-5-(morpholin-1- yl)-1H-benzimidazole: The title compound (0.2 g, 42 %) was prepared by the above general procedure using 2-[[3- methyl-4-(2,2,2-trifluorethoxy)pyridin-2-yl]methylthio]-6-fl uoro-5-(morpholin- 1 -yl)- 1 H- benzimidazole (0.5 g, 1.0 mmol) (obtained in example 8), m-chloroperbenzoic acid (50 %, 0.45 g, 1.3 mmol) and chloroform (20 mL). mp 104 - 105 OC ; IR (KBr) 3417, 1070 cm-1; 1H NMR (CDCl3) # 2.20 (s, 3H, CH3), 3.08 (m, 4H, N(CH2)2), 3.92 (m, 4H, O(CH2)2), 4.40 (q, J = 6.1 Hz, 2H, OCH2CF3), 4.80 (ABq, J = 10.2 Hz, Av = 6.0 Hz, 2H, SOCH2), 6.72 (d, J = 5.6 Hz, 1H), 7.18 (d, J = 8.0 Hz, 1H), 7.28 (d, J = 9.6 Hz, lH), 8.38 (d, J = 5.7 Hz, 1H), 12.00 (brs, 1H, NH); Mass (m/z) 472 (M+.).

Example 56 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsul finyl]-6-fluoro-5-(morpholih-1- yl)-1H-benzimidazole, sodium salt:

The title compound (0.04 g, 82 %) was prepared by the above general procedure using 2-[[3- methol-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methlsulfinyl] - 6-fluoro - 5 -(morpholin- 1 -yl)- 1 H- benzimidazole (0.047 g, 0.1 mmol) (obtained in example 55) and 0.1 N NaOH solution (1.0 mL, 0. 1mmol). mp 141 - 142 OC ; IR (KBr) 1452, 1021 cm-1; IHNMR (DMSO-d6) 6 2.28 (s, 3H, CH3), 3.00 (m, 4H, N(CH2)2), 3.82 (m, 4H, O(CH2)2), 4.60 (ABq, J = 10.0 Hz, Av = 54.0 Hz, 2H, SOCH2), 4.92 (q, J = 5.6 Hz, 2H, OCH2CF3), 7.06 (d, J = 5.2 Hz, 1H), 7.12 (d, J = 7.6 Hz, lH), 7.22 (d, J = 9.8 Hz, 1H), 8.32 (d, J = 5.4 Hz, 1H).

Example 57 2-[[(4-Methoxy-3-methyl) pyridin-2-yl]methylsulfinyl]-6-fluoro-5-(morphonlin-1-yl)-1H - benzimidazole : The title compound (0.18 g, 60 %) was prepared by the above general procedure using 2-[[(4- methoxy- 3 -methyl)pyridin-2-yl]methylthio]-6-fluoro-5 5-(morpholin-1-yl)-1 H-benzimidazole (0.29 g, 0.75 mmol) (obtained in example 9), m-chloroperbenzoic acid (50 %, 0.31 g, 0.9 mmol) and dichloromethane (25 mL). mp 183 - 184 oC ; IR (KBr) 3431, 1044 cm-1; 1HNMR(CDCl3) 6 2.20 (s, 3H, CH3), 3.12 (m, 4H, N(CH2)2), 3.80 (s, 3H, OCH3), 3.98 (m, 4H, O(CH2)2), 4.80 (ABq, J = 10.2 Hz, Av = 12.6 Hz, 2H, SOCH2), 6.78 (d, J = 5.4 Hz, 1H), 7.22 (d, J = 7.6 Hz, 1H), 7.34 (d, J = 9.8 Hz, 1H), 8.38 (d, J = 5.6 Hz, 1H), 12.20 (brs, 1H, NH); Mass (m/z) 404 (M+.).

Example 58 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(morpholin-1-yl)-1H- benzimidazole, sodium salt

The title compound (0.05 g, 78 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-methyl)pyridin-2-yl]methylsulf -6-fluoro-5 -(morpholin- 1-yl)-1 H-benzimidazole (0.06 g, 0.15 mmol) (obtained in example 57) and 0.1 N NaOH solution (1.5 mL, 0.15 mmol). mp 270 - 271 OC ; IR (KBr) 1451, 1040 cm-1; 1H NMR (DMSO-d6) 6 2.18 (s, 3H, CH3), 2.90 (m, 4H, N(CH2)2), 3.74 (m, 4H, O(CH2)2), 3.88 (s, 3H, OCH3), 4.90 (ABq, J = 10.0 Hz, Av = 48.0 Hz, 2H, SOCH2), 6.92 (d, J = 5.6 Hz, 1H), 7.10 (d, J = 7.6 Hz, 1H), 7.18 (d, J = 9.5 Hz, 1H), 8.32 (d, J = 5.4 Hz, 1H).

Example 59 2-[[(4-(3-Metoxypropoxy)-3-methyl)pyridin-2-yl]methylsulfiny l]-6-fluoro-5(morpholin-1- yl)-1H-benzimidazole: The title compund (0.06 g, 56%) was prepared by the above general procedure using 2-[[(4-(3- methoxypropoxy)-3-methyl)pyridin-2-yl]methythio]-6-fluoro-5- (morpholin-1-yl)-1H- benzimidazole (0.1 G, 0.23 mmol) (obtained in example 10), m-chloroperbenzoic acid (50%, 0.1 g, 0.27 mmol) and chloroform (10 mL). mp 158 - 159 OC ; IR (KBr) 3429, 1020 cm-1; 1H NMR (CD30D) 6 2.08 (m, 2H, CH2), 2.20 (s, 3H, CH3), 3.10 (m, 4H, N(CH2)2), 3.32 (s, 3H,

OCH3), 3.58 (t, J = 4.6 Hz, 2H, OCH2), 4.88 (m, 4H, O(CH2)2), 4.16 (t, J = 4.6 Hz, 2H, OCH2), 5.18 (ABq, J = 10.0 Hz, Av = 12.0 Hz, 2H, SOCH2), 6.92 (d, J = 5.6 Hz, 1H), 7.20 (d, J = 7.2 Hz, 1H), 7.40 (d, J = 9.8 Hz, 1H), 8.00 (d, J = 5.4 Hz, 1H); Mass (m/z) 462 (M+).

Example 60 2-[[(4-(Meorpholin-1-yl)-3-methylpyridin-2-yl] methylsulfinyl] -6-fluoro-5-(morpholin-1 -yl)- 1H-benzimidazole: The title compound (0.13 g, 36 %) was prepared by the above general procedure using 2-[[(4- morpholin-1-yl)-3-methylpyridin-2-yl]melthylthio]-6-fluor-5- (morpholin-1-yl)-1H- benzimidazole (0.35 g, 0.8 mmol) (obtained in example 11), m-chloroperbenzoic acid (50 %, 0.21 g, 0.63 mmol) and dichloromethane (20 mL). mp 102 - 103 °C; IR (KBr) 3436,1580, 1018 cm-1; 1H NMR (CDCl3) 6 2. 24 (s, 3H, CH3), 2.90 (t, J =4.3Hz, H, N(CH2)2), 3.08 (t, J = 4.4 Hz, 4H, N(CH2)2), 3.82 (t, J = 4.3 Hz, 4H, (OCH2)2), 3.92 (t, J = 4.2 Hz, 4H, O(CH2)2), 4.70 (ABq, J = 14.0 Hz, Av = 12.6 Hz, 2H, SOCH2), 6.82 (d, J = 5.5 Hz, 1H), 7.16 (d, J = 6.7 Hz, 1H), 7.32 (d, J = 12.1 Hz, 1H), 8.32 (d, J = 5.4 Hz, 1H); Mass (m/z) 443 (M-16).

Example 61 2-[[4-(Morpholin-1-yl)-3-metylpyridin-2-yl]methylsulfinyl]-6 -fluoro-5-(morpholin-1-yl)- 1H-benzimidazole, sodium salt:

The title compound was prepared by the above general procedure using 2-[[4-(morpholin-1-yl)- 3-methylpyridin-2-yl]methylsulfinyl]-6-fluoro-5-(morpholin-1 -yl)-1H-beziimidazole (0.04 g, 0.8 mmol) (obtained in example 60) and 0. 1 N NaOH solution (0.8 mL, 0.08 mmol). mp 229 - 230 OC ; IR (KBr) 1582, 1032 em-1; 1HNMR(DMSO-d6) 6 2. 26 (s, 3H, CH3), 2.90 (m, 8H, 2 x N(CH2)2), 3.80 (m, 8H, 2 x O(CH2)2), 4.60 (ABq, J = 9.8 Hz, Av = 60.0 Hz, 2H, SOCH2), 6.72 (d, J = 5.4 Hz, 1H), 7.12 (d, J = 7.2 Hz, 1H), 7.18 (d, J = 10.4 Hz, 1H), 8.30 (d, J = 5.3 Hz, 1H).

Example 62 2- [(4-(Piperidin-1-yl)-3-methylpyridin-2-yl)methylsulfinyl] -6-fluoro-5-(morpholin-1-yl)-1 H- benzimidazole:

The title compound (0.1 g, 22 %) was prepared by the above general procedure using 2-[[4- (piperidin-1-yl)-3-melthylpyridin-2-yl]methylthio]-6-fluoro- 5-(morpholin-1-yl)-1H- benzimidazole (0.44 g, 1.0 mmol) (obtained in example 12). m-chloroperbenzoic acid (50 %, 0.4 g. 1.1 mmol)anddichloromethane(l0mL).mp 116- 117°C; IR(KBr) 3422, 1580, 1041 cm-1; 1H NMR (CDCl3) # 1.50 - 1.75 (m, 6H, (CH2) 3), 2.19 (s, 3H, CH3), 2.82 (t, J = 5.2 Hz, 4H, N(CH2)2), 3.08 (t, J = 4.3 Hz, 4H, N(CH2)2), 3.90 (t, J = 4.4 Hz, 4H, N(CH2)2), 4.76 (ABq, J = 9.5 Hz, Av = 15.9 Hz, 2H, SOCH2), 6.78 (d, J = 5.4 Hz, 1H). 7.14 (d, J = 7.6 Hz, 1H), 7.28 (d, J = 12.0 Hz, 1H), 8.24 (d, J = 5.4 Hz, 1H); Mass (m/z) 457 (M+.).

Example 63 2-[ [(3-Methyl)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(morpholin-1 -yl)-1H-benzimidazole The title compound (0.2 g, 80 %) was prepared by the above general procedure using 2-[[(3- methyl)pyridin-2-yl]methylthio] -6-fluoro-5-(morpholin-1-yl)-1H-benzimidazole (0.2 g, 0.55 mmol) (obtained in example 14), m-chloroperbenzoic acid (50 %, 0.2 g, 0.5 mmol) and dichloromethane (10 mL). mp 158 - 159 °C ; IR (KBr) 3437, 1449, 1046 cm-1; 1H NMR (CDCl3) 6 2.36 (s, 3H, CH3), 3.10 (t, J =4.6 Hz, 4H, N(CH2)2), 3.92 (t, J = 4.6 Hz, 4H, O(CH2)2), 4.70 (ABq, J = 13.8 Hz, Av = 23.1 Hz, 2H, SOCH2), 7.28 - 7.32 (m, 3H), 7.52 (d, J = 7.4 Hz, 1H), 8.42 (d, J = 4.4 Hz, 1H), 11.40 (brs, 1H, NH); Mass (m/z) 374 (M+.).

Example 64 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsufinyl]-6-fl uoro-5-(piperidin-1-yl]-1H- benzimidazole :

The title compound (0.2 g, 77 %) was prepared by the above general procedure using 2-[[(4- methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluoro-5-(pi peridin- 1 -yl)- 1 H-benzimidazole <BR> <BR> <BR> (0.2 g, 0. 5 mmol) (obtained in example 15), m-chloroperbenzoic acid (50 %, 0.2 g, 0.6 mmol) and chloroform (20 mL). mp 95 - 96 OC ; IR (KBr) 3422, 1077 cm-1 ; 1H NMR (DMSO-d6) 6 1.58 (m, 2H, CH2), 1.70 (m, 4H, (CH2)2), 2.18 (s, 3H, CH3), 2.22 (s, 3H, CH3), 3.00 (m, 4H, N(CH2)2), 3.70 (s, 3H, OCH3), 4.76 (ABq, J = 13.3 Hz, Av = 15.2 Hz, 2H, SOCH2), 7.20 (d, J = 8.0 Hz, 1H), 7.46 (d, J = 12.4 Hz, 1H), 8.20 (s, 1H); Mass (m/z) 416 (M+).

Example 65 2-[[(4-Methoxy-3,5-dimethyl)pyridin-2-yl]methylsulfinyl]-6-f luoro-5-(piperidin-1-yl)-1H- benzimidazole, sodium salt: The title compound (0.07 g, 95 %) was prepared by the above general procedure using 2-[[4- methoxy-3,5-dimethylpyridin-2-yl]methylsulfinyl]-6-fluoro-5- (piperidin-1-yl)-1H- benzimidazole, (0.07 g, 0. 17 mmol) (obtained in example 64), 0. 1 N NaOH solution (1.7 mL, 0.17 mmol). IR (KBr) 1470, 1027 cm-1; IHNMR (DMSO-d6) 6 1.56 (m, 2H, CH2), 1.70 (m, 4H, (CH2) 2), 2.24 (s, 3H, CH3), 2.92 (s, 3H, CH3), 3.46 (m, 4H, N(CH2)2), 3.72 (s, 3H, OCH3),

4.54 (ABq, J = 13.0Hz, Av = 50.0Hz, 2H, SOCH2), 7.12 (d, J = 5.0 Hz, lH), 7.16 (d, J = 84. Hz, 1H), 8.26 (s, 1H0.

Example 66 2-[[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsul finyl]-6-fluoro-5-(piperidin-1- yl)-1H-benzimidazole: The title compound (0.18 g, 78 %) was prepared by the above general procedure using 2-[[3- methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylthio]-6-f luoro-5-(piperidin-1-yl)-1H- benzimidazole (0.23 g, 0.5 mmol) (obtained in example 16), m-chloroperbenzoic acid (50 %, 0.2 g, 0.6mmol) and chloroform (20 mL). mp 99-100 OC ; IR (KBr) 3413, 1070 cm-1; 1H NMR (DMSO-d6) 6 1.52 (m, 2H, CH2), 1.70 (m, 4H, (CH2)2), 2.20 (s, 3H, CH3) 3.98 (t, J = 4.5 Hz, 4H, N(CH2)2), 4.80 (ABq, J = 12.9 Hz, Av = 9.1 Hz, 2H, SOCH2), 4.94 (q, J = 8.1 Hz, 2H, OCH2CF3), 7.12 (d, J = 5.8 Hz, 1H), 7.18 (d, J = 7.8 Mz, 1H), 7.44 (d, J = 12.7 Hz, 1h), 8.32 (d, J = 5.5 Hz, 1H); Mass (m/z) 454 (M-16).

Example 67 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(piperidin-l -yl)-1H- benzimidazole:

The title compound (0.1 g, 50 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-melthyl)pyridin-2-yl]methylthio]-6-fluoro-5-(piper idin-1-yl)-1H-benzimidazole (0.19 g, 0.5 mmol) (obtained in example 17), m-chloroperbenzoic acid (50 %, 0.2 g, 0.6 mmol) and chloroform (20 mL). mp 168 - 169 °C ; IR (KBr) 3432, 1096 cm-1: 1H NMR (CD30D) 6 1.60 (m, 2H, CH2), 1.80 (m, 4H, (CH2)2), 2.18 (s, 3H, CH3), 3.00 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.80 (s. 3H. OCH3), 4.80 (ABq, J = 13.8 Hz, Av = 4.2 Hz, 2H, SOCH2), 6.74 (d, J = 5.7 Hz, 1H), <BR> <BR> <BR> 7.12 (d, J = 7.6 Hz, 1H), 7.28 (d, J = 11. 8 Hz, 1H), 8.32 (d, J = 4.7 Hz, 1H); Mass (m/z) 402 (M+).

Example 68 2-[ [(4-methoxy-3-methyl)pyridin-2-yl] methvlsulfinyl]-6-fluoro-5-(piperidin-l -yl)-1H- benzimidazole, sodium salt: The title compound (0.02 g, 46 %) was prepared by the above general procedure using 2-[[4- (methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluoro-5-(p iperidin-1-yl)-1H-benzimidazole (0.04 g, 0.1 mmol) (obtained in example 67) and 0. 1 N NaOH solution (1.0 mL, 0.1 mmol). mp 164 - 165 °C ; IR (KBr) 1583, 1022 cm-1; 1HNMR(DMSO-d6) 6 1.54 (m, 2H, CH2), 1.68 (m, 4H, (CH2) 2), 2.16 (s, 3H, CH3), 2.90 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.86 (s, 3H, OCH3), 4.60 (ABq, J = 12.8 Hz, Av = 59.0 Hz, 2H, SOCH2), 6.94 (d, J = 5.4 Hz, 1H), 7.10 (d, J = 8.7 Hz, lH), 7.20 (d, J = 15.4 Hz, 1H), 8.28 (d, J = 5.7 Hz, 1H).

Example 69 2-[[(4-Piperidin-1-yl)-3-methyl)pyridin-2-yl]methylsulfinyl] -6-fluoro-5-(piperidin-1-y benzimidazole :

The title compound (0.13 g, 32 %) was prepared by the above general procedure using 2-[[(4- (piperidin-1 -yl)-3-methyl)pyridin-2-yl]methylthio]-6 1 yl)-1 H-benzimidazole (0.4 g, 0.9 mmol) (obtained in example 18), m-chloroperbenzoic acid (50 %, 0.3 g, 0.9 mmol) and chloroform (10 mL). mp 170 - 171 OC ; IR (KBr) 3430, 1580, 1022 cm-1 ; 1H NMR (CDCl3) 6 1.62 (m, 6H, (CH2) 3), 1.78 (m, 6H, (CH2)3), 2.18 (s, 3H, CH3), 2.86 (t, J = 5.3 Hz, 4H, N(CH2)2), 2.98 (t, J = 5.1 Hz, 4H, N(CH2)2), 4.70 (ABq, J = 8.8 Hz, Av = 5.6 Hz, 2H, SOCH2), 6.78 (d, J = 5.4 Hz, 1H), 7.12 (d J 5.2 Hz, 1H), 7.28 (d, J = 9.5 Hz, 1H), 8.26 (d, J = 5.4 Hz, 1H), Mass (m/z) 455 (M+).

Example 70 <BR> <BR> <BR> 2-[[ [(4-Methyoxy-3,5-dimelthyl)thyridinyl-2-yl] methylsulfinyl] -6-fluoro-5-(4-methylpiperazin- 1- <BR> <BR> <BR> <BR> <BR> yl)-1H-benzimidazole: The title compound (0.3 g, 58 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 ,5-dimethyl)pyridin-2-yl]methylthio]-6-fluoro-5-(4-methylpip erazin-1-yl)-1H-

benzimidazole (0.5 g, 1.2 mmol) (obtained in example 19), m-chloroperbenzoic acid (50 %, 0.48 g. 1.4 mmol) and chloroform (30 mL). mp 151-152 OC ; IR (KBr) 3431. 1022 cm-1; 1H NMR <BR> <BR> <BR> (DMSO-d6) # 2.20 (s, 3H, CH3), 2.24 (s. 3H, CH3). 2.30 (s. 3H CH3), 3.02 (m, 4H, N(CH2)2), 3.34 (m. 4H, N(CH2)2), 3.72 (s, 3H, OCH3), 4.76 (ABq, J = 8.6 Hz, Av = 7.1 Hz, 2H, SOCH2), 7.20 (d, J = 7.6 Hz, 1H), 7.48 (d, J = 13.5 Hz, 1H), 8.22 (s, 1H) Mass (m/z) 431 (M+).

Example 71 2-[ [3-Methyl-4-(2, 2, 2-trifluoroethoxy) pyridin-2-yll methylsulfinyl]-6-fluoro-5-(4- methylpiperazin-1 : the title compound (0.15 g, 51 %) was prepared by the above general procedure using 2-[[3- methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]melthylthi]-6-f luoro-5-(4-methylpiperazin-1-yl)- 1H-benzimidazole (0.28 g, 0.6 mmol) obtained in example 20), m-chloroperbezoic acid (50 % 0.25 g, 0.72 mmol) and chloroform (20 mL). mp 73 - 74 OC; IR (KBr) 3470, 1080 cm-1; 1H NMR (CD30D) 6 2.20 (s, 3H, CH3), 2.50 (s, 3H, CH3), 2.88 (t, J = 4.6Hz, 4H, N(CH2)2), 3.18 (t, J = 4.8 Hz, 4H, N(CH2)2), 4.68 (q, J = 8.2 Hz, 2H, OCH2CF3), 4.80 (s, 2H, SOCH2), 7.00 (d, J = 5.8 Hz, 1H), 7.24 (d, J = 7.6 Hz, 1H), 7.32 (d, J = 12.2 Hz, 1H), 8. 18 (d, J = 5.7 Hz, 1H); Mass (m/z) 486 (M+ 1).

Example 72 2-[[(4-methoxy-3,5-dimethyl)pyridin-2-ylo]methylsulfinyl]-6- fluoro-5-(4-t-butyloxycarbonyl piperazin-l-yl)-1H-benzimidazole :

The title compound (0.2 g, 42 %) was prepared by the above general procedure using 2-[[(4- methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-6-fluoro-5-(4- 5, -butyloxycabonylpiperazin-1- yl)-lH-benzimidazole (0.5 g, 1.0 mmol) (obtained in example 23) m-chloroperbenzoic acid (50 %, 0.5 g, 1.5 mmol) and chloroform (30 mL). mp 115-116°C ;IR(KBr) 3436, 1687 cm-1; <BR> <BR> <BR> 1H NMR (CDCl3) # 1.50 (s, 9H, 3 x CH3), 2.20 (s, 3H, CH3), 2.28 (s, 3H, CH3), 3.00 (t, J = 5.3 Hz, 4H, N(CH2)2), 3.60 (t, J = 5.6 Hz, 4H, N(CH2)2), 3.70 (s, 3H, OCH3), 4.72 (ABq, J = 8.6 Hz, Av = 6.7 Hz, 2H, SOCH2), 7.12 (d, J = 7.8 Hz, 1H), 7.30 (d, J = 10.4 Hz, 1H), 8.20 (s, 1H); Mass (m/z) 517 (M+).

Example 73 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfi carbonylpiperazin-1-yl)-1H-benzimidazole: The title compound (0.1 g, 45 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 -methyl)pyridin-2-yl]melthylthio]-6-bluoro-5- -(4-t-butyloxycarbonylpiperazin- 1-yl)- 1H-benzimidazole (0.25 g, 0.5 mmol) (obtained in example 24), m-chloroperbenzoic acid (40

%. 0.32 g, 0.75 mmol) and chloroform (10 mL). mp 170 - 171 °C; IR (KBr) 3420, 1695, 1096 cm-1; $1h NMR (CDCl3) # 1.50 (s, 9H, 3x CH3), 2.18 (s, 3H, CH3), 3.00 (t, J=4.4 Hz, 4H, N(CH2)2), 3.60 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.88 (s, 3H, OCH3) 4.74 (ABq, J = 12.2 Hz, Av = 14.6 Hz, 2H, SOCH2), 6.70 (d, J = 5.7 Hz, 1H), 7.10 10 (d, J = 7.8 Hz, 1H), 7.28 (d, J = 11.3 Hz, 1H), 8.30 (d, J = 5.8 Hz, 1H); Mass (m/z) 487 (M- 16).

Example 74 2-[[(4-Methoxy-3-methyl)pyridinin-2-yl]methylsulfinyl]-6-flu oro-5-(4- (ethylenedioxy)piperidin-1-yl)-1H-benzimidazole: The title compound (0.42 g, 98 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 -methyl)pyridin-2-yl]methylthio]-6-fluoro-5-(4-(ethylenediox y)piperidin- 1 -yl)- 1 H- benzimidazole (0.44 g, 1.0 mmol) (obtained in example 25), m-chloroperbenzoic acid (50 %, 0.3 g. 1.0 mmol) and dichloromethane (10 mL). mp 62 - 63 °C ; IR (KBr) 3441, 1581, 1097 cm-1 1H NMR (CDC3) # 1.94 (t, J = 5.3 Hz, 4H, (CH2)2), 2.16 (s, 3H, CH3), 3.16 (t, J = 5.4 Hz, 4H, N(CH2)2), 3.86 (s, 3H, OCH3), 4.02 (s, 4H, O(CH2)2O), 4.72 (ABq, J = 13.7 Hz, Av = 15.4 Hz, 2H, SOCH2), 6.72 (d, J = 5.6 Hz, 1H), 7.12 (d, J = 6.8 Hz, 1H), 7.26 (d, J = 8.8 Hz, 1H), 8.32 (d, J = 5.4 Hz, 1H); Mass (m/z) 444 (M - 16).

Example 75 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(4 ethylenedioxy)piperidin- l-yl)-l H-benzimidazo le, sodium salt:

The title compound (0.42 g, 99 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 -methyl)pyridin-2-yl]methylsulfinyl]-6-fluoro-5- -(4-(ethylenedioxy)piperidin- l-yl)- 1 H-benzimidazole (0.032 g, 0.07 mmol) (obtained in example 74) and 0. 1 N NaOH solution (0.7 mL, 0.07 mmol). mp 152-153 °C; IR(KBr) 1583, 1468, 1096 cm-1; IH NMR (CDC13) 6 1.84 (m, 4H, (CH2) 2), 2.20 (s, 3H, CH3), 2.98 (m, 4H, N(CH2)2), 3.70 (s, 3H, OCH3), 4.00 (s, 4H, O(CH2)2), 4.40 (s, 2H, SOCH2), 6.30 (d, J = 5.4 Hz, 1H), 6.98 (d, J = 7.5 Hz, 1H), 7.12 (d, J = 12.5 Hz, 1H), 7.84 (d, J = 5.5 Hz, 1H).

Example 76 2-! [4-melthoxy-3-methyl)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(4-piperidin-1-yl)-1H- benzimidazole: The title compound (0.25 g, 68 %) was prepared by the above general procedure using 2-[[(4- mthoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5-(4-piper idon-1-yl)-1H-bezimidaole(0.3 g, 0.75 mmol) (obtained in example 26), m-chloroperbenzoic acid (50 %, 0.26 g, 0.75 mmol) and dichloromethane (10 mL). mp 174 - 175 °C ; IR (KBr) 3426, 1715, 1043 cm-1; 1H NMR (CDCl3) 6 2.20 (s, 3H, CH3), 2.68 (t, J = 5.9 Hz, 4H, (CH2) 2), 3.40 (t, J = 6.0 Hz, 4H, N(CH2)2), 3.86 (s, 3H, OCH3), 4.72 (ABq, J = 13.7 Hz, Av = 25.0 Hz, 2H, SOCH2), 6.76 (d, J = 6.0 Hz,

1H), 7.12 (d. J = 8.2 Hz, 1H), 7.28 (d, J = 8.9 Hz, 1H), 8.32 (d, J = 5.8 Hz, 1H) ; Mass (m/z) 400 (M-16).

Example 77 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(4-piperidon-1-yl)-1H- benzimidazole, sodium salt: The title compound (0.043 g, 99 %) was prepared by the above general procedure using 2-[[(4- <BR> <BR> <BR> methoxy-3 -methyl)pyridin-2-yl]melthylsulfinyl] -6-fluoro-5-(4-piperidon- l-yl)-1H H-benzimidazole (0.04g, 0.96 mmol) (obtained in example 76) and 0.1 N NaOH solution (9.6 mL, 0.96 mmol). mp 72 - 73 °C ; IR (KBr) 1711, 1471, 1095 cm-1; IH NMR (CDCl3) 6 1.86 (s, 3H, CH3), 2.56 (m, 4H, (CH2) 2), 3.10 (m, 4H, N(CH2)2), 3.70 (s, 3H, OCH3), 4.40 (m, 2H, SOCH2), 6.38 (d, J = 5.0 Hz, 1H), 6.92 (d, J = 7.4 Hz, 1H), 7.08 (d, J = 12.2 Hz, 1H), 7.84 (d, J = 4.8 Hz, 1H).

Example 78 <BR> <BR> <BR> <BR> 2-11 (4-Methoxy-3-methyl)pyridin-2-yljmethylsulfinyl]-6-fluoro-5- (4- (hydroxypimino)piperidin-1-yl)-1H-benzimidazole: The title compound (0.25 g, 50 %) was prepared by the above general procedure using 2-[[(4- mothoxy-3-melthyl)pyridin-2-yl]melthylthio]-6-fluoro-5-(4-(h ydroxyimino)piperidin-1-yl)-1H-

benzimidazole (0.5 g, 1.2 mmol) (obtained in example 27), m-chloroperbenzoic acid (50 %, 0.4 g, 1.2 mmol) and chloroform(l0 mL). mp 196- 197°C; IR (KBr) 3421, 1583, 1021 cm-1 ; 1H <BR> <BR> <BR> <BR> NMR (DMSO-d6) # 2.12 (s, 3H, CH3), 2.42 (t, J = 5.0 Hz, 2H, CH2), 2.68 (t, J = 5.5 Hz, 2H, CH2), 3.08 (m, 4H, N(CH2)2), 3.86 (s, 3H, OCH3), 4.72 (ABq, J = 13.7 Hz, Av = 7.4 Hz, 2H, SOCH2), 6.96 (d, J = 5.6 Hz, 1H), 7.22 (d, J = 4.0 Hz, 1H), 7.46 (d, J = 11.4 Hz, 1H), 8.24 (d, J = 5.5 Hz, 1H), 10.44 (s, 1H, OH), 12.74 (s, 1H, NH); Mass (m/z) 396 (M-35).

Example 79 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methyssulfinyl]-6-fluoro-5-(4-hydroxypiperidin-1- yl)-1H-benzimidazole: The title compound (0.15 g, 88 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-methyl)pyridin-2-yl]melthylthio]-6-fluoro-5-(4-hyd roxypiperidin- 1 -yl)- 1 H- benzimidazole (0.2 g, 0.5 mmol) (obtained in example 28), m-chloroperbenzoic acid (50 %, 0.5 mmol, 0.17 g) and dichloromethane (10 mL). mp 66 - 68 OC ; IR (KBr) 3415, 1079 cm-1; IH NMR (CDCl3) # 1.78 - 1.86 (m, 2H, CH2), 2.00- 2.16 (m, 2H, CH2), 2.20 ( s, 3H CH3), 2.86 (t, J = 9.2 Hz, 2H, NCH2), 3.36 (t, J = 6.4 Hz, 2H, NCH2), 3.87 (s, 3H, OCH3), 3.82 - 3.94 (m, 1H, OCH), 4.20 (s, 1H, OH), 4.68 (ABq, J = 13.7 Hz, Av = 22.1 Hz, 2H, SOCH2), 6.74 (d, J = 5.7 Hz, 1H), 7.08 (d, J = 7.2 Hz, 1H), 7.32 (d, J= 11.8 Hz, 1H), 8.32 (d,J = 5.4 Hz, 1H), 11.70 (brs, 1H, NH). Mass (m/z) 418 (M+.).

Example 80 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(hexamiethyleneimin-1-yl)- 1H-benzimidazole:

The title compound (0. 15 g, 48 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5-(hexame thyleneimin-1-yl)-1H- benzimidazole (0.3 g, 0.75 mmol) (obtained in example 29), m-chloroperbenzoic acid (50 %, 0.1 g, 0.6 mmol) and dichloromethane (20 mL). mp 144 - 145 °C ; IR (KBr) 3429,1587, 1097 cm-l ; 1H NMR (CDCl3) # 1.66 (m, 4H, (CH2)2), 1.86 (m, 4H, (CH2)2), 2.18 (s, 3H CH3), 3.28 (t, J = 5.5 Hz, 4H, (CH2) 2), 3.86 (s, 3H, OCH3), 4.76 (ABq, J = 13.4 Hz, Av = 10.4 Hz, 2H, SOCH2), 6.74 (d, J = 5.8 8Hz, lH), 7.00 (d, J = 6.7 Hz, lH), 7.28 (d, J = 8.4 Hz, lH), 8.32 (d, J=5.7 Hz, 1H0 ; Mass (m/z) 400 (M-16).

Example 81 2- [[(4-Methyox-3-methyl)pyridin-2-yl] methylsulfinyl]-6-fluoro-5-(hexamethyleneimin-1-yl)- 1H-benzimidazole, sodium salt: The title compound (0.04 g, 95 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 -methyl)pyridin-2-yl]melthoxulfinyl]-6-fluoro-5-(hexamethyle neimin- 1 -yl)- 1 H- benzimidazole (0.04 g, 0.9 mmol) (obtained in example 80) and 0.1 N NaOH (1.0 mL, 0.1

mmol). mp 202 - 203 °C ; IR (KBr) 1585, 1098 cm-1; 1H NMR (CDCl3) 6 1.64 (m, 4H, (CH2) 2), 1.80 (m. 4H, (CH2)2), 2.18 (s, 3H, CH3), 3.18 (t, J = 5.0 hz, 4H, N(CH2)2), 3.86 (s, 3H, OCH3), 4.54 (ABq. J = 12.8 Hz, Av = 61.4 Hz, 2H, SOCH2) 6.94 (d, J = 5.5 Hz, 1H), 7.08 (d, J = 7.5 Hz, 1H), 7. 12 (d, J = 9.4 Hz, 1H), 8.30 (d, J = 5.4 Hz, 1H).

Example 82 2-[[(4-(Morpholin-1-yl)-3-melthyl)pyridin-2-yl]methylsulfiny l]-6-fluoro-5- (hexamethyleneimin-1-yl)-1H-benzimidazole: The title compound (0.15 g, 35 %) was prepared by the above general procedure using 2-[[(4- morpholin-1-yl)-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5 -(hexamethyleneimin-1-yl)-1H- benzimidazole (0.42 g, 0.92 mmol) (obtained in example 30) m-chloroperbenzoic acid (50 %, 0. 16 g 0.92 mmol) and dichloromethane (10 mL). mp 162 - 163 °C ; IR (KBr) 3439, 1577, 1051 cm IH NMR (CDCl3) 6 1.66 (m, 4H, (CH2)2), 1.86 (m, 4H, (CH2)2), 2.18 (s, 3H, CH3) 2.88 (t, J = 4.4 Hz, 4H, N(CH2)2), 3.32 (t, J = 5.0 Hz, 4H, N(CH2)2), 3.82 (t, J = 4.5 Hz, 4H, O(CH2)2), 4.70 (ABq, J = 8.2 Hz, Av = 4.3 Hz, 2H, SOCH2), 6.80 (d, J = 5.6 Hz, 1H), 6.94 (d, J = 7.1 Hz, 1H), 7.24 (d, J = 10.2 Hz, 1H), 8.34 (d, J = 5.4 Hz, 1H); Mass (m/z) 455 (M-16).

Example 83 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluor o-5-(2- (methoxymethyl)pyrrolidin-1-yl)-1H-benzimidazole:

The title compound (0.2 g. 40 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-methyl)pyridin-2-yl]methylthio]-6-fluoro-5 -(2-(methoxymethyl)pyrrolidin- 1-yl)-1H- benzimidazole (0.5 g, 2.0 mmol) (obtained in example 31), m-chloroperbenzoic acid (50 %, 0.16 g 0.96 mmol) and dichloromethane (10 mL). IR (Neat) 3340, 1581, 1098 cm-1; 1H NMR (CDCl3) 6 1.84-2.08 (m, 4H, (CH2) 2), 2.20 (s, 3H CH3), 3.10-3.22 (m, 2H, NCH2), 3.26 (s, 3H, OCH3), 3.40- 3.64 (m, 2H, OCH2), 3.88 (s, 3H OCH3), 4.00- 4.16 (m, 1H, OCH), 4.74 (ABq, J = 8.2 Hz, Av = 10.8 Hz, 2H, SOCH2), 6.76 (d, J = 5.4 Hz, 1H), 6.92 (d, J = 7.5 Hz, 1H), 7.30 (d, J = 14.4 Hz, 1H), 8.34 (d, J = 5.4 Hz, 1H); Mass (m/z) 416 (M-16).

Example 84 2-[[(4-Melthoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-6-fluo ro-5-(pyrrolidin-1-yl)-1H- benzimidazole:

The title compound (0.18 g, 34 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-mehtyl)pyrdin-2-yl}methylthio]-6-fluoro-5-(pyrrrol idin 1 -yl)- 1 H-benzimidazole (0.5 g. 1.3 mmol) (obtained in example 32), m-chloroperbenzoic acid (50 %, 0.45 g. 1.3 mmol) and chloroform (10 mL). mp 90-91 °C ; IR (Neat) 3434, 1581, 1040cm-1; 1H NMR (CDCl3) 6 1.98 (m, 4H, (CH2) 2), 2.14 (s, 3H, CH3), 3.36 (m, 4H, N(CH2)2), 3.84 (s, 3H, OCH3), 4.72 (ABq, J = 13.7 Hz, Av = 7. 9 Hz, 2H, SOCH2), 6.70 (d, J = 5.4 Hz, 1H), 7.28 (d, J = 6.3 Hz, 1H), 7.32 (d, J=8.4 Hz, 1H), 8.30 (d,J =5.4 Hz, 1H); Mass (m/z) 372 (M-16).

Example 85 2-1 [(4-methoxy-3,5-dimethyl)pyridin-2-yl] methylsulfinyl]-5-(morpholin-1-yl)-1H- benzimidazole: The title compound (0.17 g 60 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 ,5-dimethyl)pyridin-2-yl]methylthio]-5-( 1-yl)-1 H-benzimidazole (0.27 g, 0.7 mmol) (obtained in example 33), m-chloroperbenzoic acid (50 %, 0.28 g, 0.84 mmol) and chloroform (20 mL). mp 97 - 98 OC ; IR (KBr) 3418, 1075 cm 1H NMR (CD3OD) # 2. 16 (s, 3H, CH3), 2.24 (s, 3H, CH3), 3.16 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.70 (s, 3H, OCH3), 3.90 (t, J = 4.8 Hz, 4H, O(CH2)2), 4.74 (ABq, J = 9.8 Hz, Av = 5.6 Hz, 2H, SOCH2), 7.08 (s, 1H), 7.14 (d, J = 9.0 Hz, 1H), 7.54 (d, J = 9.1 Hz, 1H), 8.12 (s, 1H); Mass (m/z) 400 (M+).

Example 86 2-[[3-Methyl-4-(2,2,2-trifluroethoxy)pyrridin-2-yl]methylsul finyl]-5-(morpholin-1-yl)-1H- benzimidazole:

The title compound (0.28 g, 62 %) was prepared by the above general procedure using 2-[[3- methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylthio]-5-( morpholin- 1 -yl)- 1 H-benzimidazole (0.44 g 1.0 mmol) (obtained in example 34), m-chloroperbenzoic acid (50 %. 0.41 g. 1.2 mmol) in chloroform (20 mL). mp 102 - 103 OC ; IR (KBr) 3431, 1043 cm-1; 1H NMR (CD30D) 6 2.18 (s, 3H CH3), 3.18 (t, J = 4.6 Hz, 4H, N(CH2)2), 3.86 (t, J = 4.6 Hz, 4H, O(CH2)2), 4.64 (q, J = 6.2 Hz, 2H, OCH2CF3), 4.80 (ABq, J = 8.3 Hz, Av = 4.5 Hz, 2H, SOCH2), 6.98 (d, J = 5.7 Hz, 1H), 7.08 (s, 1H), 7.14 (d, J = 9.9 Hz, 1H), 7.52 (d, J = 9.0 Hz, lH), 8.22 (d, J=5.8 Hz, 1H); Mass (m/z) 454 (M+).

Example 87 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]melthylsulfi benzimidazole : The title compound (0.16 g, 52 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 -methyl)pyridin-2-yl]methylthio]-5-(morpholin- 1 -yl)- 1 H-benzimidazole (0.3 g, 0.8 mmol) (obtained in example 35), m-chloroperbenzoic acid (50 %, 0.41 g, 1.2 mmol) and chloroform (10 mL). mp 158- 159°C ; IR (KBr) 3429, 1044 cm-1; lH NMR (CD30D) 6 2.12

(s, 3H, CH3), 3.16 (t, J = 4.7 Hz, 4H, N(CH2)2), 3.86 (t, J = 4.9 Hz, 4H, O(CH2)2), 3.90 (s, 3H, OCH2), 4.74 (ABq, J = 13.2 Hz, Av = 5.9 Hz, 2H, SOCH2), 6.92 (d, J = 5.6 Hz, 1H), 7.08 (s, lH), 7.14 (d, J = 9.2 Hz, 1H), 7.52 (d, J = 9.2 Hz, lH), 8.18 (d, J = 5.7 Hz, 1H); Mass (m/z) 386 (M+).

Example 88 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-5-(morp holin-1 -yI)-1H- benzimidazole, sodium salt: The title compound (0.03 g, 71 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 -methyl)pyridinin-2-yl]methylsufinyl]-5-(morpholin- 1 -yl)- 1 H-benzimidazole (0.04 g, 0.1 mmol) (obtained in example 87) and 0.1 N NaOH solution (1.0 mL, 0.1 mmol). mp 79 - 80 °C; IR (KBr) 1583, 1040 cm-1; 1H NMR (DMSO-d6) # 2.20 (s, 3H, CH3), 3.00 (t, J = 4.7 Hz, 4H, N(CH2)2), 3.76 (t, J = 4.6 Hz, 4H, O(CH2)2, 3.88 (s, 3H, OCH3), 4.60 (ABq, J = 12.8 Hz Av = 65.9 Hz, 2H, SOCH2), 6.72 (d, J = 6.7 Hz, 1H), 6.94 (d, J = 5.6 Hz, 1H), 6.98 (s, 1H), 7.34 (d, J = 8.7 Hz, 1H), 8.32 (d, J = 5.4 Hz, 1H).

Example 89 <BR> <BR> <BR> 2- z [(4-Methoxy-3,5-dimethyl)pyridin-2-yl] methylsulfinyl] -5-(4-melthylpiperazin-1 -yl)-1H- benzimidazole:

The title compound (0.2 g, 65 %) was prepared by the above general procedure using 2-[[(4- methoxy-3,5-dimethyl)pyridin-2-yl]methylthio]-5-(4-methylpip erazin-1-yl)-1 H-benzimidazole (0.3 g, 0.75 mmol) (obtained in example 36), m-chloroperbenzoic acid (50 %. 0.26 g, 1.2 mmol) and chloroform (30 mL). IR (KBr) 3422, 1447, 1076 cm-1; 1H NMR (CDCl3) 6 2.16 (s, 3H, CH3), 2.26 (s, 3H, CH3), 2.36 (s, 3H, NCH3), 2.66 (t, J = 4.7 Hz, 4H, N(CH2)2), 3.20 (t, J = 4.6 Hz. 4H, N(CH2)2), 3.76 (s, 3H, OCH3), 4.52 (s, 2H, SOCH2), 6.99 (d, J = 8.6 Hz, 1H). 7.04 (s, lH) 7.40 (d, J = 9.3 Hz, 1H), 8.14 (s, 1H); Mass (m/z) 413 (M+).

Example 90 2-[[(4-metoxy-3methyl)pyridin-2-yl]methylsulfinyl]-5-(4-t-bu tyloxycarbonylpiperazin-1- yl)-1H-benzimidazole: The title compound (0.11 g, 54 %) was prepared by the above general procedure using 2-[[(4- methoxy-3 -methyl)pyridin-2-yl]methylthio]-5-(4-t-butyloxycarbonylpipe razin- l-yl)-1H- benzimidazole (0.2 g, 0.42 mmol) (obtained in example 38), m-chloroperbenzoic acid (50 %, 0.21 g, 0.63 mmol) and chloroform (20 mL). mp 169 - 170 OC ; IR (KBr) 3427, 1696, 1070 cm- <BR> <BR> <BR> 1; 1H NMR (CDCl3) # 1.48 (s, 9H, 3 x CH3), 2.14 (s, 3H, CH3), 3.14 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.60 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.88 (s, 3H, OCH3), 4.76 (ABq, J = 10.2 Hz, Av = 5.4 Hz, 2H, SOCH2), 6.92 (d, J = 5.8 Hz, 1H), 7.12 (d, J = 9.0 Hz, 1H), 7.18 (s, lH), 7.54 (d, J = 8.9 Hz, 1H), 8.32 (d, J = 5.8 Hz, 1H); Mass (m/z) 469 (M-16).

Example 91 2-[[(4-Methoxy-3-methyl)pyridin-2-yl]methylsulfinyl]-5-(hexa methyleneimin-1-yl)-1H- benzimidazole:

The title compound (0.15 g, 36 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-methyl)pyridin-2-yl]methylthio]-5-(hexamethyleneim in-1-yl)-1H-benzimindazole (0.4 g 1.0 mmol) (obtained in example 40), m-chloroperbenzoic acid (50 % 0.34 g, 1.0 mmol) and dichloromethane (10 mL). mp 158 - 159 °C ; IR (KBr) 3435, 1581, 1045 cm-1; 1H NMR (CDCl3) # 1.58 (m, 4H, CH2)2), 1.82 (m, 4H, (CH2)2), 2.20 (s, 3H, CH3), 3.52 (t, J = 5.7 Hz, 4H, N(CH2)2), 3.88 (s, 3H, OCH3), 4.74 (ABq, J = 13.3 Hz, Av = 13.7 Hz, 2M, SOCH2), 6.74 (d, J = 5.5 Hz, 1H), 6.82 (d, J = 9.4 Hz, 1H), 7.27 (s, 1H), 7.52 (d, J = 9.1 Hz, 1H), 8.36 (d, J = 5.5 Hz. 1H), 11.12 (brs, 1H, NH); Mass (m/z) 382 (M-16).

Example 92 2-[ [(4-Methoxy-3-methyl)pyridin-2-yl] methylsulfinyl]-4,6-diflouoro-5-(morphonlin-1 -yl)-1H- benzimidazole: The title compound (0.18 g, 44 %) was prepared by the above general procedure using 2-[[(4- methoxy-3-methyl)pyridin-2-yl]methylthio]-4,6-difluoro-5-mor pholin-1-yl)-1H-bezimidazole (0.4 g, 1.0 mmol) (obtained in example 41), m-chloroperbenzoic acid (40 %, 0.55 g, 1.28 mmol)

and chloroform (20 mL). mp 186-187°C ; IR (KBr) 3441, 1582, 1040 cm-1; 1H NMR (CDCl3) 6 2.20 (s, 3H, CH3), 3.22 (t, J = 4.5 Hz, 4H, N(CH2)2), 3.82 (t, J = 4.3 Hz, 4H, N(CH2)2), 3.90 (s, 3H, OCH3), 4.80 (ABq, J = 13.9 Hz, Av = 10.9 Hz, 2H, SOCH2), 6.76 (d, J = 5.8 Hz, 1H), 7.05 (d, J = 10.4 Hz, 1H), 8.32 (d, J = 5.5 Hz, 1H); Mass (m/z) 422 (M+).

The compounds of the present invention have been tested for their anti-ulcer activity via H / K -ATPase inhibition activity using standard state of the art in vitro as well as in vivo pharmacological protocols.

A) H+/K-, ATPase inhibition The most efficient method for reducing acid-related gastrointestinal disorder is through the inhibition of proton pump on the gastric parietal cell. The proton pump (H+/ K ATPase) is a membrane bound enzyme that exchanges protons for K+ ions across the apical surface.

Associated with this is a K+/ Cl - cotransporter which recycles the K+ together with the Cl- across the apical surface where HCl is formed by the Cl- ions together with the secreted H+.

This enzyme has an ATP hydrolyzing activity which requires intravesicular K+ Principle H+/K+ ATPase ATP ---------------------------------------- > ADP + P Pj liberated is estimated, the amount of Pi liberated is proportional to the enzyme activity.

(i) Preparation of H+/K+-ATPase Rabbit gastric mucosa containing H+/K+ - ATPase activity is isolated according to the modified method of Reenstra et al. (Reenstra, W.W. & Forte, J. G. Methods in enzymology 1990, 92: 551). After homogenizing the fundic mucosa in buffer (5 mM PIPES, 0.25 M sucrose, 0.2

mM EDTA, pH 6.8), the high speed supernatant is layered over 20 mL of 37% sucrose bed and subjected to ultracentrifugation at 25,000 rpm (SW-28 rotor) for 4 h at 4 °C. The interfacial layer is collected and diluted with homogenization buffer. subjected to ultracentrifugation at 25,000 rpm for 1 hour. The pellet thus obtained is used for enzyme assay.

(ii) Measurement of the activity of H+/K - ATPase Assay is carried out according to the protocol described by Beil R (Beil, R. Br. J.

Pharmacol, 1984, 82: 651). The compound of the present invention was incubated at various concentrations with H+/K - ATPase and the membrane protein (10 llg/mL) in assay medium containing 50 mM Tris buffer solution having a pH of 6.5, 250 mM sucrose, 3 mM MgCl2, 50 µM valinomycin with or without 10 mM KCl for 10 minutes (total volume 1 mL). The enzyme reaction is initiated by adding ATP to a final concentration of 3 mM. After incubation for 15 min. at 37 °C. the reaction is stopped by adding equal volume of phosphate reagent and the Pi produced by the hydrolysis of ATP is determined by the method of Lin et al. (Lin T-I. & Morales, M. F. Anal. Biochem. 1977, 77. 10). The H+/K - ATPase activity is calculated by subtracting the basal activity (in absence of KCI) from the rate of hydrolysis of ATP in the presence of K4. The percent inhibition were determined for the test compounds. Example No. %Inhibition at 10mg/kg Example No. $%Inbhibition at 10 mg/kg Example 67 100 Example 82 100 Example 68 100 Example 84 93 Example 69 97 Example 87 90 Example 73 93 Example 90 100 Example 80 100 Example 91 97 Example 81 100 Omeprazole 75 B) Gastric acid antisecretory activity

The inhibitory effect on gastric acid secretion is determined in pylorus ligated rat model according to Shay et al. (Shay, M., Komarov, S. A., Fels, D., Merange, D., Gruenstein, H. & Siplet, H. Gastroenterology 1945, 5: 43). Male wistar rats weighing about 150-200 g fasted for 24 h with ad libitum are used. Under ether anaesthesia the laparotomy is performed and pylorus portion of the stomach is isolated and ligated with surgical suture. The test drug/vehicle is administered intraduodenally and the abdominal incision is closed using Michael clips. After 2 h, the animals were sacrificed with excess ether anaesthesia and stomach is removed. The gastric contents are collected and centrifuged at 10,000 rpm for 10 min. The volume of the gastric juice is measured and acid concentration is estimated by titrating an aliquot of the gastric juice against 0.004 N NaOH using phenolphthalein as the indicator. Total acid output is expressed as milliequivalents/L/kg/h and volume of gastric juice as mL/kg/h. The ED50 value for the test compound is calculated according to graphical method. Omeprazole is used as a standard compound.

The test compounds are compared at a dose of 10 mg/kg.

The IC50 value for the inhibition of H+/K+ ATPase of compound of example 57 which is a representative of the compounds of the present invention has been found to be 2.6 pM and whereas the IC50 value for Omeprazole is 4.35 + 0.56 pM. In the in vivo experiment, the ED50 value of compound of Example 57 is found to 3.0+0.2 mg/kg whereas the ED50 value for Omeprazole is 4.96+0.5 mg/kg.