Patent ID: 8552039

Claim:
A compound of formula: wherein R 1 and R 2 are each independently H, OH, cyano, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, CF 3 , halo or NR 4 R 4′ ; R 3 is H; R 4 is H, COR 5 , SO 2 R 6 or C 1 -C 6 alkyl; R 4′ is H or C 1 -C 6 alkyl; R 5 is H or C 1 -C 6 alkyl; R 6 is H or C 1 -C 6 alkyl; n is 4, 5, 6 or 7; or a pharmaceutical salt thereof.