. . "ompound of the formula (II): or a protected form thereof, with hydrazine hydrate and then cyclising; or (iii) the reaction of a compound of the formula (III): or a protected form thereof, wherein Y is a groups which can be converted to an amide e.g. methyl, carboxylic acid, carboxylic ester, halide; and then converting to an amide;and thereafter removing any protecting group present;wherein X1-5," . .