On July 27, 2006, Venkatesan, Aranapakam M.; Agarwal, Atul; Abe, Takao; Ushirogochi, Hideki; Yamamura, Itsuka; Ado, Mihira; Tsuyoshi, Takasaki; Dos Santos, Osvaldo; Gu, Yansong; Sum, Fuk-Wah; Li, Zhong; Francisco, Gerry; Lin, Yang-I.; Petersen, Peter J.; Yang, Youjun; Kumagai, Toshio; Weiss, William J.; Shlaes, David M.; Knox, James R.; Mansour, Tarek S. published an article.COA of Formula: C9H12N2O3 The title of the article was Structure-Activity Relationship of 6-Methylidene Penems Bearing 6,5 Bicyclic Heterocycles as Broad-Spectrum β-Lactamase Inhibitors: Evidence for 1,4-Thiazepine Intermediates with C7 R Stereochemistry by Computational Methods. And the article contained the following:
The design and synthesis of a series of 6-methylidene penems containing [6,5]-fused bicycles (thiophene, imidazole, or pyrazle-fused system) as novel class A, B, and C β-lactamase inhibitors is described. These penems proved to be potent inhibitors of the TEM-1 (class A) and AmpC (class C) β-lactamases and less so against the class B metallo-β-lactamase CcrA. Their in vitro and in vivo activities in combination with piperacillin are discussed. On the basis of the crystallog. structures of a serine-bound reaction intermediate of imidazo[2,1-c]oxazine I with SHV-1 (class A) and GC1 (class C) enzymes, compounds II (R = Q, Q1, Q2, etc.) were designed and synthesized. Penems are proposed to form a seven-membered 1,4 thiazepine ring in both class A and C β-lactamases. The interaction energy calculation for the enzyme-bound intermediates favor the formation of the C7 R enantiomer over the S enantiomer of the 1,4-thiazepine in both β-lactamases, which is consistent with those obtained from the crystal structure of I with SHV-1 and GC1. The experimental process involved the reaction of Ethyl 6,7-dihydro-5H-pyrazolo[5,1-b][1,3]oxazine-2-carboxylate(cas: 153597-59-2).COA of Formula: C9H12N2O3
The Article related to methylidene penem preparation beta lactamase inhibitor structure activity, bactericide methylidene penem structure activity, Biomolecules and Their Synthetic Analogs: Beta-Lactam Fungal Metabolites and other aspects.COA of Formula: C9H12N2O3
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics