Process for the preparation of clavulanic acid derivatives and compounds used as intermediates therein.

摘要

A process is described for the preparation of a compound of the formula (I): <CHEM> wherein R<1> is a group such that CO2R<1> is an ester group; which process comprises the base catalysed elimination of carbon dioxide and a compound of the formula (II): H2N.COR<2> (II) wherein R<2> is an inert moiety, from a compound of the formula (III): <CHEM> wherein R<1> is as defined in relation to formula (I) and R<2> is as defined as in relation to formula (II). The compounds of the formula (III) and their preparation also form part of the invention.