Abstract: Compounds of the following formula (I) wherein R1 R2, n, Ar1 and A2 are as defined in the specification, in vivo-hydrolysable precursors thereof, pharmaceutically acceptable salts thereof, the use in therapy and pharmaceutical compositions and methods of treatment using the same. The example compounds are 1-(2-(naphthylmethoxy)-1-phenylethyl)piperazine derivatives.