School of Pharmaceutical Sciences & Collaborative Innovation Center of New Drug Research and Safety Evaluation, Zhengzhou University, Zhengzhou 450001, China
Department of Urology, University of California, Irvine, Orange, CA 92868, USA
Author to whom correspondence should be addressed.
Molbank 2018, 2018(3), M1016; https://doi.org/10.3390/M1016
Received: 11 August 2018 / Revised: 25 August 2018 / Accepted: 28 August 2018 / Published: 30 August 2018
(This article belongs to the Collection Molecules from Catalytic Processes)
Efficient large-scale and feasible industrial synthesis of the 1-oxacephem core structure from 6-aminopenicillanic acid (6-APA) has been reported for several decades. Via the industrial synthesis route, a byproduct (compound 9) containing a butenolide unit was purified and characterized by NMR and HRMS in this work. It is worth noting that compound 9 is an entirely new compound. Additionally, a plausible mechanism and effects on the formation of 9 by different Lewis acids were proposed. The discovery of compound 9 could improve the purity of this feasible industrial synthesis and provide considerable cost savings.