Patent ID: 7803820

Claim:
A compound of formula (I) or a pharmaceutically acceptable salt thereof: wherein R 1 is hydrogen or C 1-4 alkyl; R 2 is C 1-4 alkyl; R 3 is hydrogen, or a phenyl group, a heterocyclyl group, a 5- or 6-membered heteroaromatic group, or a 8- to 11-membered bicyclic group, any of which groups is optionally substituted by 1, 2, 3 or 4 substituents selected from the group consisting of: halogen, cyano, C 1-4 alkyl, haloC 1-4 alkyl, C 1-4 alkoxy, C 1-4 alkanoyl and SF 5 ; p is 0, 1, 2, 3 or 4; and R 4 is independently selected from a group consisting of: halogen, hydroxy, cyano, C 1-4 alkyl, haloC 1-4 alkyl, C 1-4 alkoxy, haloC 1-4 alkoxy and C 1-4 alkanoyl; n is 0 or 1; wherein when R 4 is chlorine and p is 1, such R 4 is not present in the ortho position with respect to the linking bond to the rest of the molecule; and wherein, if n is 0, R 3 comprises at least one SF 5 group as a substituent.