Patent ID: 8357716

Claim:
A compound of formula (I) or a salt thereof wherein R 1 is selected from the group consisting of (1), (2), (3) (4) and (5) (1) a group of formula (a) in which A is selected from the group consisting of (i), (ii), (iii), (iv), (v), (vi) , (vii) and (viii) (i) hydrogen; (ii) C 1-6 alkyl optionally substituted by one or more —NR a R b , —OR c , —C(O)NR a R b , —C(O)OR c , heterocyclyl, phenyl or heteroaryl groups; (iii) C 3-7 cycloalkyl optionally substituted by a —C(O)OR c or —NR a R b group; (iv) heterocyclyl optionally substituted by one or more C 1-6 alkyl; (v) heteroaryl optionally substituted by one or more halogen or C 1-6 alkyl; (vi) —NR a R b ; (vii) phenyl substituted by a —(CH 2 ) p C(O)OH group in which p is 0, 1, 2 or 3; or (viii) —(CH 2 ) 7 C(O)OH (2) a group of formula (b) in which B is C 1-6 alkyl; (3) —C(O)NR a R b or —CH 2 C(O)NR a R b ; (4) —S(O) 2 NR a R b ; (5) C 1-6 alkoxy optionally substituted by NR a R b ; R a , R b and R c are independently hydrogen or C 1-6 alkyl; R 2 is halogen, C 1-6 alkyl, CF 3 , hydroxy or C 1-6 alkoxy; R 3 is halogen, CF 3 , hydroxy, C 1-6 alkoxy, CR d R e OH or CHF 2 ; in which R d and R e are independently hydrogen or methyl; R 4 is hydrogen, halogen, C 1-6 alkyl or CF 3 ; R 5 and R 6 are independently hydrogen, halogen or C 1-6 alkyl; and n is 0 or 1.