A simple and ecofriendly method was developed for the synthesis of arylmethylene[bis(5,5- dimethyl-3-hydroxy-2-cyclohexene-1-ones)] from the reaction of 5,5-dimethylcyclohexane- 1,3-dione and aromatic aldehydes in an aqueous media without any catalyst via Knoevenagel condensation followed by rapid Michael addition. No cyclization product was down to convert these enolic forms to xanthene deriva...

OBJECTIVES Carbapenem-hydrolysing class D β-lactamases of the OXA-48 type are increasingly reported from Enterobacteriaceae. β-Lactamase OXA-48 hydrolyses penicillins very efficiently, but carbapenems only weakly and spares broad-spectrum cephalosporins. Recently, diverse OXA-48-like β-lactamases have been identified worldwide (OXA-162, OXA-181, OXA-163, OXA-204 and OXA-232). They differ by few...

Abstract A major challenge in the treatment of infections has been rise extensively drug resistance (XDR) and multidrug (MDR) Acinetobacter baumannii . The goals this study were to determine pattern antimicrobial susceptibility, bla OXA carO genes among burn-isolated A. strains. In study, 100 strains isolated from burn patients their susceptibilities different antibiotics determined using disc ...

Background and Objective: Pseudomonas aeruginosa (P. aeruginosa) causes serious nosocomial and non-nosocomial infections. blaOxacillinases (OXA)-23 and blaOXA24/40 provide resistance to carbapenem antibiotics. The aim of this study was assessment of blaOXA-23 and blaOXA-24/40 in P. aeruginosa isolated from patients with nosocomial and non-nosocomial infections. Me...

An example of diastereoselective and enantioselective synthesis of thiochroman derivatives through a sulfa-Michael-Michael cascade sequence is disclosed. This is a significant complement of the quinine-thiourea catalyzed sulfa-Michael-Michael cascade reaction. The densely functionalized target thiochromans were obtained in high diastereoselectivities, and with high to excellent enantioselectivi...

Complex natural products are a proven and rich source of disease-modulating drugs and of efficient tools for the study of chemical biology and drug discovery. The architectures of complex natural products are generally considered to represent significant barriers to efficient chemical synthesis. Here we describe a concise and efficient asymmetric synthesis of 19-dehydroxyl arisandilactone A-whi...

A novel and convenient organocatalytic tandem reaction has been developed for the asymmetric assembly of saturated aldehydes (or enals), nitroolefins and isatins to produce six-membered oxa-spirooxindole backbones bearing four contiguous stereogenic centers and multiple functional groups with high stereoselectivity.

OBJECTIVES This study was designed to demonstrate the prevalence of the newly discovered carbapenem-hydrolysing class D enzymes, OXA-51-type and OXA-58, among clinical isolates of Acinetobacter spp. METHODS A total of 72 isolates from six centres were studied. Isolates were screened by PCR with specific primers for bla(OXA-51-type) and bla(OXA-58). PCR products were sequence-analysed. Plasmid...

An interesting sequential reaction involving Sonogashira coupling, propargyl-allenyl isomerization, intramolecular [4 + 2] cycloaddition, and bridged oxa-ring opening has been realized, providing a facile method for the synthesis of functionalized dihydroisobenzofurans from easily accessible starting materials with a decent diastereoselectivity.