Patent ID: 8916599

Claim:
A compound of formula Ib, in which R 1 and R 2 independently represent chloro, bromo, fluoro, C 1-3 alkyl (which latter alkyl group is optionally substituted by one or more fluoro-atoms); R 3 , R 3a and R 4 : independently represent hydrogen, chloro, bromo, fluoro, C 1-3 -alkyl (which latter alkyl group is optionally substituted by one or more fluoro atoms); R 6 represents hydrogen or C 1-4 alkyl optionally substituted by one or more fluoro atoms; R 8 represent hydrogen, fluoro, chloro, —O—C 1-4 alkyl (optionally substituted by one or more fluoro atoms); A represents phenyl, C 3-10 cycloalkyl, C 1-12 linear or branched alkyl, all of which are optionally substituted by one or more substituents selected from R 9 ; R 9 represents, on each occasion when used herein: halo, —OR y10 ; C 1-7 alkyl, cycloalkyl, (which latter two groups are optionally substituted by one or more substituents selected from fluoro, —OR y10 ; R y10 represents hydrogen or C 1-4 alkyl optionally substituted by one or more halo atoms or —OC 1-2 alkyl groups; or a pharmaceutically acceptable salt thereof.