Preparation, isolation, and characterization of dimeric degradation products of the 1 beta-methylcarbapenem antibiotic, ertapenem

Dimeric degradates of ertapenem, a novel broad-spectrum 1 beta -methyl carb apenem antibiotic currently in development, have been prepared by controlle d degradation of the bulk drug substance in concentrated solutions and isol ated by preparative HPLC. The degradates were characterized by LC/MS and NM R and result from various bimolecular reactions of the carbapenem leading t o dimers and dehydrated dimers. The development of selective degradation pr ocedures was critical in facilitating isolation of the degradates, and prov ided a better understanding of the degradation process. This report will fo cus on the development of preparative chromatographic methods for isolation of these highly unstable compounds.