| abstract |
A compound of formula (I) or a pharmaceutically acceptable salt thereof:n in which one of X and Y represents hydrogen and the other represents Z, where Z is a groupn in which Q represents a 3-membered divalent residue completing a 5-membered aromatic ring and comprises one heteroatom selected from oxygen, nitrogen and sulphur or two heteroatoms selected from sulphur and nitrogen, any amino nitrogen being optionally substituted by a C 1 - 2 alkyl, and at least one ring carbon atom being substituted by a group Ri; or a groupn in which A 1 , A 2 and As complete a 5-membered aromatic ring and A 1 is oxygen or sulphur, A 2 is CR 2 and As is nitrogen or CH, or A 2 is oxygen or sulphur, A 1 is CH and As is CR 2 ; and R 1 and R 2 are selected from, halogen, CN, OR 4 , SR 4 , N(R 4 ) 2 , NHCOR 4 , NHCOOCH 3 , NHCOOC 2 Hs, NHOR 4 , NHNH 2 , N0 2 , COR 4 , CORs, C 2-4 alkenyl, C 2-4 alkynyl or C 1-2 alkyl substituted with OR 4 , N(R 4 ) 2 , SR 4 , CO 2 R 4 , CON(R 4 ) 2 or one, two or three halogen atoms, in which each R4 is independently hydrogen or C 1-2 alkyl and R s is OR 4 , NH 2 or NHR 4 ; r represents an integer of 2 or 3, s represents an integer of 1 or 2 and t represents 0 or 1, with the proviso that when Y is hydrogen s is 1. |