title: Epimerization of benzylpenicilloic acid in alkaline media.
abstract: 5R,6R-Benzylpenicilloic acid was found to epimerize slowly in alkaline media to 5S,6R-benzylpenicilloic acid until equilibrium was established. Epimerization proceeded via the imine tautomer of penamaldic acid rather than the enamine form and was found to favor the 5S,6R-epimer at equilibrium. The conversion process was monitored using both reverse-phase high-performance liquid chromatography and NMR spectroscopy.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D010400:Penicillin G / Q000031:analogs & derivatives* / Q000032:analysis; D011048:Polarography; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: C030990:benzylpenicilloic acid; D010400:Penicillin G