Patent ID: 8067619

Claim:
A compound of formula (I) wherein R 1 is selected from the group consisting of hydrogen, halogen, cyano, nitro, CF 3 and —O—SO 2 —CF 3 ; R 2 is selected from the group consisting of hydrogen, halogen, cyano, nitro, CF 3 and —O—SO 2 —CF 3 ; provided that R 1 and R 2 are not each hydrogen; a is an integer from 0 to 1; L 1 is selected from the group consisting of —C(O)—, —CH(OH)— and —C(O)—NR A —; wherein R A is selected from hydrogen or C 1-4 alkyl; R 3 is selected from the group consisting of hydrogen, C 1-4 alkyl, C 2 alkenyl, aryl and heteroaryl; wherein the aryl or heteroaryl is optionally substituted with one or more substituents independently selected from halogen, hydroxy, C 1-4 alkyl, C 1-4 alkoxy, cyano, nitro or CF 3 ; alternatively, -L 1 -R 3 is selected from methoxy methyl or 2-(Trimethylsilyl)ethoxy methyl; provided that when a is 0, then R 3 is other than hydrogen or C 1-4 alkyl; provided further that when a is 1 and L 1 is —CH(OH)—, then R 3 is other than hydrogen; R 4 is selected from the group consisting of hydrogen, aryl, —C(O)-aryl, 6-membered heteroaryl and —C(O)-(6 membered heteroaryl); wherein the aryl or heteroaryl group, whether alone or as part of a substituent group is optionally substituted with one or more substituents independently selected from halogen, hydroxy, C 1-4 alkyl, C 1-4 alkoxy, cyano, nitro or CF 3 ; provided that when R 1 is hydrogen or halogen, R 2 is hydrogen, a is 0 and R 3 is 4-hydroxy-phenyl, then R 4 is other than 4-chlorophenyl; provided further that when R 1 is halogen, R 2 is hydrogen, a is 1, L 1 is —C(O)NH— and R 3 is phenyl, then R 4 is other than hydrogen; or a pharmaceutically acceptable salt thereof.