CLAVULANIC ACID DERIVATIVES, THEIR PREPARATION AND PHARMACEUTICAL COMPOSITIONS

摘要

The compounds of the formula (I): and pharmaceutically acceptable salts and in-vivo hydrolysable esters thereof wherein X is a sulphur atom or SO or SO2 group and R is a hydrogen atom or an alkyl group of 1 to 6 carbon atoms have been found to be beta -lactamase inhibitors and antibacterial agents. Their preparation and use is described.