title: Isolation and structure elucidation of a novel product of the acidic degradation of cefaclor.
abstract: The acidic aqueous degradation of cefaclor, an orally administered cephalosporin antibiotic, has been investigated. The most prominent peak in the high-performance liquid chromatography profile of a degraded solution of cefaclor was isolated by preparative high-performance liquid chromatography. Mechanistically, the formation of this degradent from cefaclor involves a condensation of two cefaclor degradation products in which both products have undergone contraction from a six-membered cephem ring to a five-membered thiazole ring, presumably via a common episulfonium ion intermediate.
authors.affiliation: Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285-0724.
authors.forename: S W
authors.initials: SW
authors.lastname: Baertschi
authors.forename: D E
authors.initials: DE
authors.lastname: Dorman
authors.forename: J L
authors.initials: JL
authors.lastname: Occolowitz
authors.forename: L A
authors.initials: LA
authors.lastname: Spangle
authors.forename: M W
authors.initials: MW
authors.lastname: Collins
authors.forename: M E
authors.initials: ME
authors.lastname: Wildfeuer
authors.forename: L J
authors.initials: LJ
authors.lastname: Lorenz
mesh_terms: D002433:Cefaclor / Q000737:chemistry* / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D006851:Hydrochloric Acid; D009682:Magnetic Resonance Spectroscopy; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002433:Cefaclor; D006851:Hydrochloric Acid