A simple monocyclic 8n electron thiepin, 2,7-di-tert-butyl-4-ethoxycarbonyl-5-methylthiepin (13) stabilized by two bulky tert-butyl groups at 2and 7-positions, was synthesized from 2,6-di-tert-butyl-4-methylthiopyrylium tetrafluoroborate (11). In spite of of its monocyclic thiepin structure, the compound 13 showed remarkable thermal stability and had a half-life of 7.1 h at 130 °C. Judging from...

Two methods of preparing sensitivity disks were compared for their effect on disk stability at 25 and 37 C. One method consisted of applying a solution of the antibiotic to blank disks by the conventional procedure; the second method consisted of applying the antibiotic to the disks as a suspension of crystals. Of the four beta-lactam antibiotics that were studied, disks made with suspended cry...

Enantioselective reductive desymmetrization of glutarimides has been achieved employing an oxazaborolidine catalyst derived from cis-1-amino-indan-2-ol. The reaction was found to proceed through a stereoablative process that upgraded the enantioselectivity of an intermediate hydroxy-lactam. The reaction was generally tolerant of a number of substituents in the 4-position, giving enantiomeric ex...

Objective: Class B carbapenemases are bacterial enzymes that catalyze the hydrolysis of β-lactam core antibiotics, except for monobactams. The objective this study was to identify carbapenemase gene blaIMP in genus Klebsiella at Charles De Gaulle Pediatric University Hospital (CHUP-CDG) Ouagadougou, Burkina Faso. Methods: involved 17 strains responsible human infection and isolated from various...

Metallo β-lactamases is the name given to certain enzymes found in gram negative bacteria belonging to Enter-obacteriaceae which confers resistance to all β-lactam antibiotics including carbapenems except monobactams. They belong to Ambler molecular class B and Bush-Jacoby-Medeiros Group 3.1,2 Resistance to carbapenems due to production of metallo β-lactamases in Gram Negative organisms is an i...

Metallo-β-lactamase-producing Pseudomonas aeruginosa (MPPA) is an important nosocomial pathogen that shows resistance to all β-lactam antibiotics except monobactams. There are various types of metallo-β-lactamases (MBLs) in carbapenem-resistant P. aeruginosa including Imipenemase (IMP), Verona integron-encoded metallo-β-lactamase (VIM), Sao Paulo metallo-β-lactamase (SPM), Germany imipenemase (...

Resistance to the expanded-spectrum cephalosporins has become a worldwide problem. Such resistance occurs primarily in members of the family Enterobacteriaceae via the production of extendedspectrum β-lactamases (ESBLs), which are capable of hydrolyzing the oxyimino-cephalosporins and monobactams (Bush et al., 2001; Pitout et al., 2004). It has recently been shown that the CTX-M β-lactamases ar...

Carbapenemases are a large and diverse family of microbial enzymes that hydrolyze not only carbapenems but also other b-lactams, with the occasional exception of monobactams, such as aztreonam. For clinicians, the nomenclature of carbapenemases, like that of other b-lactamases, is confusing. In keeping with other b-lactamases, carbapenemases can be classified on the basis of function or structu...