7-Oxo-4-thia-1-azabicyclo¬3,2,0 hept-2-ene derivatives

摘要

A compound of formula I
with R' being an alkyl group substituted by one or more substituents and esters thereof at the 2-carboxy group or at the 8-hydroxy group or both: and salts thereof. Compounds I have antibacterial effect. Various intermediates are described. This compound of the formula I, or an ester at the 2-carboxy group or at the 8-hydroxy group or both or a salt thereof is produced by reacting a compound of formula II or of formula IX
in which R represents a hydrogen atom or a carboxy protecting group, R³ represents an activated carboxylic acid group, R⁴ represents an alkyl group having 1 to 4 carbon atoms, or a phenyl group which may be unsubstituteo or substituted, R¹⁵ represents a phenyl group or an alkyl group having from 1 to 4 carbon atoms, and X represents an oxygen c, sulphur with an amine of the formula III R'NH₂ (III), to give a compound of formula I, or an ester therecf of formula la