Patent ID: 8188091

Claim:
A compound of formula (I) or an optical isomer thereof, or a pharmaceutically acceptable salt or hydrate thereof, wherein R 1 represents hydrogen, (C 1 -C 4 )-alkyl, (C 2 -C 4 )-alkenyl, (C 2 -C 6 )-acyl, sulfonyl or benzoyl, R 2 represents a 5- or 6-membered aryl or heteroaryl mono-substituted or multiple-substituted with the same or different substituents selected from: hydrogen, halogen, hydroxyl, cyano, trifluoromethyl, nitro, benzyl, (C 1 -C 6 )-alkyl, (C 1 -C 6 )-alkoxyl, (C 1 -C 6 )-alkylthio, (C 1 -C 6 )-alkoxylcarbonyl, (C 1 -C 6 )-acyloxy, amino, (C 1 -C 6 )-alkylamino, (C 1 -C 6 )-dialkylamino, and (C 1 -C 6 )-acylamino, R 3 represents an aryl or heteroaryl mono-substituted or multiple-substituted with the same or different substituents selected from: hydrogen, halogen, trifluoromethyl, trifluoromethoxyl, trifluoromethanesulfonyl, nitro, cyano, carboxyl, hydroxyl, (C 1 -C 6 )-alkoxyl, (C 1 -C 6 )-alkoxycarbonyl and (C 1 -C 6 )-alkyl, wherein the alkyl can be substituted with an aryl having 6-10 carbon atoms, halogen, or a group represented by —S—R 5 , NR 6 R 7 , CO—NR 8 R 9 or -A-CH 2 —R 10 , wherein R 5 represents phenyl which can be optionally substituted with halogen, R 6 , R 7 , R 8 and R 9 are the same or different, and independently represents hydrogen, phenyl, hydroxyl-substituted phenyl, hydroxyl, (C 1 -C 6 )-acyl or (C 1 -C 6 )-alkyl, wherein the alkyl can be substituted with hydroxyl, halogen, (C 1 -C 6 )-alkoxycarbonyl, phenyl or hydroxyl-substituted phenyl, A represents O, S, SO or SO 2 , R 10 represents phenyl optionally mono- or multiple-substituted with same or different substituents selected from: halogen, nitro, trifluoromethyl, (C 1 -C 6 )-alkyl and (C 1 -C 6 )-alkoxy, and R 4 represents an optionally mono- or multiple-substituted, the same or different substituent selected from: hydrogen, halogen, nitro, cyano, hydroxyl, (C 1 -C 6 )-alkyl, (C 1 -C 6 )-alkoxyl, (C 1 -C 6 )-alkoxylcarbonyl, aryl and heteroaryl having 6-10 carbon atoms, wherein the aryl or heteroaryl can be substituted with halogen or (C 1 -C 6 )-alkyl.