Patent ID: 8168642

Claim:
A compound of formula (I) or a pharmaceutically acceptable salt thereof, wherein R 1 represents hydrogen, (C 1 -C 4 )-alkyl, (C 2 -C 4 )-alkenyl, (C 2 -C 6 )-acyl or benzoyl, R 2 represents one or more substituents independently selected from: hydrogen, halogen, hydroxyl, cyano, trifluoromethyl, nitro, benzyl, (C 1 -C 6 )-alkyl, (C 1 -C 6 )-alkoxy, (C 1 -C 6 )-alkylthio, (C 1 -C 6 )-alkoxycarbonyl, (C 1 -C 6 )-acyloxy, amino, (C 1 -C 6 )-alkylamino, (C 1 -C 6 )-dialkylamino, or (C 1 -C 6 )-acylamino, R 3 represents one or more substituents independently selected from: hydrogen, halogen, trifluoromethyl, trifluoromethoxy, trifluoromethylsulfonyl, nitro, cyano, carboxy, hydroxyl, (C 1 -C 6 )-alkoxy, (C 1 -C 6 )-alkoxycarbonyl and (C 1 -C 6 )-alkyl, wherein said alkyl may be substituted by aryl having from 6 to 10 carbon atoms, halogen, or a group presented by formulae —S—R 6 , NR 7 R 8 , CO—NR 9 R 10 and -A-CH 2 —R 11 , wherein R 6 represents phenyl optionally substituted by halogen, R 7 , R 8 , R 9 and R 10 , the same or different, respectively represent hydrogen, phenyl, hydroxyl-substituted phenyl, hydroxyl, (C 1 -C 6 )-acyl or (C 1 -C 6 )-alkyl, wherein said alkyl may be substituted by hydroxyl, halogen, (C 1 -C 6 )-alkoxycarbonyl, phenyl or hydroxyl-substituted phenyl, A represents O, S, SO or SO 2 , R 11 represents phenyl optionally substituted with one or more groups independently selected from: halogen, nitro, trifluoromethyl, (C 1 -C 6 )-alkyl and (C 1 -C 6 )-alkoxy, R 4 represents a group represented by formula —XR 12 or —NR 13 R 14 , wherein X represents oxygen or a bond, R 12 represents hydrogen, a straight or branched (C 1 -C 6 )-alkoxycarbonyl, or a straight, branched or cyclic, saturated or unsaturated (C 1 -C 8 )-hydrocarbyl, wherein said hydrocarbyl optionally includes one or two identical or different heterochain unit(s) selected from the group consisting of O, CO, NH, —NH(C 1 -C 4 )-alkyl, —N((C 1 -C 4 )-alkyl) 2 , S and SO 2 , and may be optionally substituted by halogen, nitro, cyano, hydroxyl, aryl having from 6 to 10 carbon atoms, aralkyl, heteroaryl or a group represented by formula —NR 15 R 16 , wherein R 15 and R 16 , the same or different, respectively represent hydrogen, benzyl or (C 1 -C 6 )-alkyl, R 13 and R 14 , the same or different, respectively represent hydrogen, benzyl, (C 1 -C 6 )-alkyl, or cycloalkyl having from 3 to 6 carbon atoms, R 5 represents hydrogen, benzyl, (C 1 -C 6 )-alkyl, wherein said alkyl may be substituted by hydroxyl, halogen, (C 1 -C 6 )-alkoxycarbonyl, phenyl or substituted phenyl.