Patent ID: 7799774

Claim:
A compound of formula (I): wherein: R 1 represents hydrogen, methyl, ethyl, isopropyl, isobutyl or 2,2-dimethylpropyl; R 2 represents hydrogen, methyl, or is linked to R 1 to form a (CH 2 ) 3 group; R 3 represents hydrogen, methyl or halogen; R 4 and R 5 independently represent hydrogen or methyl; n represents 1; p represents 1 or 2; m represents 1 or 2, or m is 2 and both R 2 groups are linked to form a CH 2 group linking C-2 and C-5 of the piperizine ring; A represents a group —Ar 1 , wherein Ar 1 represents unsubstituted phenyl or phenyl substituted by halogen, cyano, C 1-6 alkyl, C 1-6 alkoxy, trifluoromethyl or trifluoromethoxy; or a pharmaceutically acceptable salt thereof.