Gamma-lactonecarboxylic acid derivatives and their use as antibacterial agents or intermediates

摘要

A compound represented by formula (I): <IMAGE> (I) wherein R1 is an organic residue through a carbon atom, R2 is a carboxyl group which may be esterified or amidated, and X is an oxygen atom, or a sulfur atom which may be oxidized, or a salt thereof, which is useful as antibacterial agent or intermediate for synthesizing the same, and a process for preparing the same.