beta -Lactam antibacterial agents

摘要

Compounds are described of the formula (II): <IMAGE> (II) wherein R1 is a group such that CO2R1 is an ester group; A1 is a hydrogen atom; and A2 is a group CR2R3R4 wherein R2 is a hydrogen atom or a hydroxyl group; R3 is a hydrogen atom or a lower alkyl group; and R4 is a hydrogen atom or a lower alkyl group, a benzyl group, a phenyl group or is joined to R3 to form part of a C5-7 carboxylic ring or is a group of the formula CH(OH)R5 or CHX wherein R5 is a hydrogen atom or lower alkyl group and X is an oxygen atom or a CR6R7 group where R6 is a hydrogen atom or a lower alkyl, phenyl, CN, CO2R8 where R8 is a lower alkyl, phenyl or benzyl group and R7 is a hydrogen atom or a lower alkyl group or is joined to R6 to form part of a C5-7 carbocyclic ring. These compounds have been found to possess antibacterial properties. The preparation of these compounds is described.