High-performance liquid chromatographic assay of temocillin and epimerisation of its diastereoisomers

Abstract

Assay of temocillin by a high-performance liquid chromatographic method that resolves the diastereoisomers is described and potential difficulties in the chromatographic quantitation of a compound that contains two isomers are discussed. Nuclear magnetic resonance spectra of the separate diastereoisomers were used to assign the R and S configuration of the side-chain to the first and second eluting isomers, respectively. Epimerisation of the isomers was investigated and equilibration half-lives and the isomer composition at equilibrium were determined.