Process for the preparation of therapeutically useful substituted 3-aminomethyl cephalosporins and novel intermediates

摘要

A cephalosporin derivative of the formula I: IMAGE I in which X is S, O, CH2 or SO, R1 is (optionally-substituted)imidazol-2-yl or one of the C-7 acyl groups known in the cephalosporin art, R2 is hydrogen or methoxy, R3 is carboxy or a biodegradable ester thereof and -R4 is of the formula XII, XIII or XIV: IMAGE +TR IMAGE in which R32-R40 inclusive are as defined in the specification; and the salts thereof. Pharmaceutical compositions, methods of manufacture and intermediates are also described.