Mixed Anhydrides of Penicillinic and Cephalosporinic Acids with N - Acyl Carbamic Aci ~ 1
نویسنده
چکیده
Mixed anhydrides with penicillinic acids (III) were unstable and gave N-acyl, amides IV. Only III with butyrolactam was stable and reacted with alcohols to give esters V. All anhydrides with cephalosporinic acids (VIlI) yielded symmetric anhydrides IX. Alcoholysis of IX gave cephalosporinic ester X, while aminolysis yielded amide. Formation of postulated isomeric mixed anhydride with O-imino carbonic acid ester XlIIb is discussed.
منابع مشابه
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