title: N-formylpenicillamine and penicillamine as degradation products of penicillins in solution.
abstract: The degradation of several penicillins in unbuffered aqueous solution produces N-formylpenicillamine, in some cases in high yield. Very little or no penicillamine is formed under these conditions. N-Formylpenicillamine was produced from benzylpenicillin at pH values between 2.5 and 7, with a maximum yield of 30% at pH 5, whereas penicillamine was produced only at pH 5 or below in a yield of less than 1%. Benzylpenicillenic acid at pH 5 gave a 20% yield of N-formylpenicillamine and no penicillamine whereas benzylpenicilloic, penilloic and penillic acids gave no N-formylpenicillamine and a small amount of penicillamine.
mesh_terms: D000658:Amoxicillin / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D006863:Hydrogen-Ion Concentration; D010396:Penicillamine / Q000032:analysis*; D010406:Penicillins / Q000032:analysis*; D012996:Solutions
chemical_list: D010406:Penicillins; D012996:Solutions; D000658:Amoxicillin; D010396:Penicillamine