Patent ID: 7981889

Claim:
A compound of the formula (Ib): or an isomer or salt thereof, or a mixture of any thereof, wherein: A and B together represent a fused aromatic ring, optionally substituted with one or more substituent groups selected from halo, nitro, hydroxyl, ether, thiol, thioether, amino, C 1-7 alkyl, C 3-20 heterocyclyl and C 5-20 aryl; R x is selected from H, C 1-20 alkyl, C 5-20 aryl, C 3-20 heterocyclyl, amido, thioamido, ester, acyl, and sulfonyl groups, wherein the acyl, C 1-20 alkyl, C 5-20 aryl or C 3-20 heterocyclyl group is optionally substituted with one or more substituent groups selected from C 1-20 alkyl, C 5-20 aryl, C 3-20 heterocyclyl, halo, hydroxyl, ether, nitro, cyano, acyl, carboxy, ester, amido, amino, acylamido, ureido, acyloxy, thiol, thioether, sulfoxide, sulfonyl, thioamido and sulfonamido; R C1 and R C2 are both hydrogen; and R 1 is selected from H and halo.