Patent ID: 7935832

Claim:
A compound of formula (I), or a pharmaceutically acceptable salt thereof: wherein: R 1 represents C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl, C 3-6 cycloalkylmethyl- or pyridinylmethyl-, any of which is optionally substituted with 1, 2 or 3 halogen atoms; or unsubstituted phenyl or benzyl; and R 2 represents hydrogen, halogen, C 1-6 alkyl, C 6-10 arylmethyl-, C 2-6 alkenyl, C 2-6 alkynyl or C 3-6 cycloalkylmethyl-; and any of said C 1-6 alkyl, C 6-10 arylmethyl-, C 2-6 alkenyl, C 2-6 alkynyl or C 3-6 cycloalkylmethyl- is optionally substituted with 1, 2 or 3 halogen atoms; and R 3 represents hydrogen, fluorine or methyl; or R 2 and R 3 together with the carbon atoms to which they are attached form a benzene ring optionally substituted with 1, 2 or 3 substituents, which may be the same or different, selected from the group consisting of C 1-6 alkyl, C 2-6 alkenyl and C 2-6 alkynyl; R 4 represents hydrogen, fluorine or methyl; and R 5 , R 6 , R 7 , R 8 and R 9 independently represent hydrogen, halogen, cyano, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl or phenyl, and any of said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl or phenyl is optionally substituted with 1, 2 or 3 halogen atoms; or R 8 and R 9 together with the carbon atoms to which they are attached form a benzene ring which is optionally substituted with 1, 2 or 3 halogen atoms; with the proviso that when R 5 and R 9 are both selected from hydrogen or fluorine, at least one of R 6 , R 7 and R 8 is a halogen atom.