THIAZOLE DERIVATIVES AND THEIR USE IN THE MANUFACTURE OF BETA LACTAM ANTIBIOTICS

摘要

The invention provides crystalline (Z)-2-(2-t-butoxycarbonyl-prop-2-oxyimino)-2-(2-triphenylmethylaminoth iazol-4-yl)acetic acid in association with dioxan and its crystalline ethyl ester in association with methanol. The compounds are of value as intermediates in the preparation of beta -lactam antibiotics such as ceftazidime or azthreonam.