Phthalazinone derivatives

摘要

Compounds of the formula (I): wherein A and B together represent an optionally substituted, fused aromatic ring; X can be NR or CRR; if X NR then n is 1 or 2 and if X = CRR then n is 1; R is selected from the group consisting of H, optionally substituted C1-20 alkyl, C5-20 aryl, C3-20 heterocyclyl, amido, thioamido, ester, acyl, and sulfonyl groups; R is selected from H, hydroxy, amino; or R and R may together form a spiro-C3-7 cycloalkyl or heterocyclyl group; R and R are both hydrogen, or when X is CR R, R, R, R and R, together with the carbon atoms to which they are attached, may form an optionally substituted fused aromatic ring; and R<1> is selected from H and halo.