The 7alpha-methoxy substituent in cephem or oxacephem antibiotics enhances in vivo anti-Helicobacter felis activity in mice after oral administration

2′-Chloro-4-(1-methyl-1H-imidazol-2-yl)-2,4′-bipyridine

The compound 2′-chloro-4-(1-methyl-1H-imidazol-2-yl)-2,4′-bipyridine was obtained with a good yield by the reaction of 2-chloro-4-(1-methyl-1H-imidazol-2-yl)pyridine with (2-chloropyridin-4-yl)boronic acid and structurally characterized by nuclear magnetic resonance (1H-NMR and 13C-NMR), thin-layer chromatography–mass spectrometry (TLC–MS), HPLC, gas chromatography–mass spectrometry (GC–MS), and elemental analysis. The functionalization of the pyridine was achieved by the palladium-catalyzed Suzuki–Miyaura carbon–carbon cross-coupling reaction that afforded the target compound.

(1R,5S)-6-(4-Methyl-2-oxo-2,5-dihydrofuran-3-yl)-3-phenyl-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-en-7-one

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.