Patent ID: 7745439

Claim:
An indene compound defined by formula (I) or a pharmaceutically acceptable salt thereof: wherein, R 1 is —OCH 3 , —OC 2 H 5 , —NH 2 , —NHCOCH 3 , —NHCOC 2 H 5 , —N(C 2 H 5 ) 2 , —NHC 2 H 5 , R 2 is CO 2 R a , CONHR b or CN; R 3 is phenyl; and R 4 is —OCH 3 , —O(CH 2 ) 3 R c , —O(CH 2 ) 2 R d , —CH 2 R d or in which R a is H, methyl or ethyl; R b is cyclohexyl; R c is phenyl; and R d is