Patent ID: 8217028

Claim:
A compound of formula (I) or a pharmaceutically acceptable salt thereof: wherein R 5 is (a) and attached at any one of positions 4, 5, 6 or 7 of the indole group; A is a phenyl or a 5 or 6-membered heteroaryl ring; R 1 is hydrogen or up to three substituents independently selected from halogen, C (1-6) alkyl, C (3-6) cycloalkyl, C (1-6) alkoxy, C (3-6) cycloalkyloxy, trifluoromethoxy, difluoromethoxy, trifluoromethyl, cyano, nitro, optionally substituted piperidine, optionally substituted pyrrolidine, optionally substituted phenyl and optionally substituted 5 or 6 membered heteroaryl rings; when R 1 is phenyl, piperidine, pyrrolidine or a 5 or 6 membered heteroaryl ring it may be substituted by up to three substituents selected from halogen, C (1-6) alkyl, C (1-6) alkoxy, trifluoromethoxy, difluoromethoxy, C 3-6 cycloalkyl, trifluoromethyl and cyano; R 2 is hydrogen or up to three substituents independently selected from halogen, C (1-4) alkyl, C (1-4) alkoxy, trifluoromethoxy, difluoromethoxy, trifluoromethyl and cyano; one of R 3 and R 4 is hydrogen or C (1-6) alkyl and the other is Z—COOH or C (1-6) alkylOH; Z is absent, C (1-6) alkyl or C (2-6) alkenyl; when Z is C (1-6) alkyl it is optionally interrupted by cyclopropyl, piperidinyl, azetidinyl, pyrrolidinyl, N or O and optionally substituted by O, cyclopropyl halogen or methyl, when Z is C (2-6) alkenyl it is optionally substituted by methyl. R 6 is hydrogen or C (1-6) alkyl.