Dear Editor,The Enterobacterales are an order of Gram-negative bacteria comprising a few major human pathogens such as Escherichia coli and Klebsiella pneumoniae.However,carbapenem-resistant Enterobacterales(CRE)has r...Dear Editor,The Enterobacterales are an order of Gram-negative bacteria comprising a few major human pathogens such as Escherichia coli and Klebsiella pneumoniae.However,carbapenem-resistant Enterobacterales(CRE)has risen as an urgent threat for human health,leading to high mortality with very limited antimicrobial options.The main mechanism mediating resistance to βlactams including carbapenems in the Enterobacterales is production of β-lactamases,which are two categories of enzymes capable of hydrolyzing β-lactams:serine β-lactamases and metallo β-lactamases(MBLs).展开更多
A compound ethyl(5S,6R)-2-(4-methylphenyl)-6-[(1R)-tert-butyldimethylsilyloxyethy]-penem-3-carboxylate was synthesized through displacement,acylation and Wittig cyclization reaction of optically active material(3R,4R)...A compound ethyl(5S,6R)-2-(4-methylphenyl)-6-[(1R)-tert-butyldimethylsilyloxyethy]-penem-3-carboxylate was synthesized through displacement,acylation and Wittig cyclization reaction of optically active material(3R,4R)-3-[(1R)-tert-butyldimethylsilyloxyethyl]-4-acetoxy-2-azetidi-none(4AA)upon thionocarboxlic acid.The intermediates and the target product were characterized by 1HNMR,IR,elementary analysis and MS.展开更多
基金supported by the National Natural Science Foundation of China(Grants No.82172309 and 81861138055)the 1.3.5 Project for Disciplines of Excellence from West China Hospital of Sichuan University(Grant No.ZYGD22001).
文摘Dear Editor,The Enterobacterales are an order of Gram-negative bacteria comprising a few major human pathogens such as Escherichia coli and Klebsiella pneumoniae.However,carbapenem-resistant Enterobacterales(CRE)has risen as an urgent threat for human health,leading to high mortality with very limited antimicrobial options.The main mechanism mediating resistance to βlactams including carbapenems in the Enterobacterales is production of β-lactamases,which are two categories of enzymes capable of hydrolyzing β-lactams:serine β-lactamases and metallo β-lactamases(MBLs).
文摘A compound ethyl(5S,6R)-2-(4-methylphenyl)-6-[(1R)-tert-butyldimethylsilyloxyethy]-penem-3-carboxylate was synthesized through displacement,acylation and Wittig cyclization reaction of optically active material(3R,4R)-3-[(1R)-tert-butyldimethylsilyloxyethyl]-4-acetoxy-2-azetidi-none(4AA)upon thionocarboxlic acid.The intermediates and the target product were characterized by 1HNMR,IR,elementary analysis and MS.
