1. A compound of formula I or formula II:, or a pharmaceutically acceptable salt thereof, gdeZ represents - (CH) -, wherein x is 1, 2, 3 or 4 or -O- (CH) -, where z is 2, 3 or 4 each X independently represents CH or N each X independently represents C, S or N X represents CH, S, or NH each of R and independently represents H, C-alkyl or halogenoalkyl each independently represents aryl, alkyl, cycloalkyl, or haloalkyl, wherein each of said alkyl, haloalkyl and cycloalkyl groups optionally comprising hetero atoms O or N in place of carbon atoms in the chain, and two adjacent ROn ring atoms or the same atom, together with the annular ring (s) atom (s) to which they are attached, optionally form a 3-8-membered ring y equals 0, 1, 2, 3 or 4 R is - (alkylene) -heterocyclyl, - (alkylene) -heteroaryl, - (alkylene) -NRR, - (alkylene) -C (O) NRR - (alkylene) -C (O) -O-alkyl - (alkylene) -O-R, - (alkylene) -S (O) -Rili - (alkylene) -S (O) -NRR, any of which may be optionally independently substituted with one or more Rgruppami, in accordance with a valency and wherein two Rgruppy associated with the same or an adjacent atom may optionally combine to form a ring, and wherein m is 0 or 1 and n is 0, 1 or 2 r and R b each case independently represent: (i) hydrogen or (ii) alkyl, cycloalkyl, heterocyclo, aryl, heteroaryl, cycloalkylalkyl, heterocycloalkyl, arylalkyl, or heteroarylalkyl, any of which may be optionally optionally independently substituted by one or more Rgruppami, in accordance with the valency and wherein two Rgruppy associated with the same or an adjacent atom may optionally be combined with an image
