Efficient and one-pot synthesis of 1,8-dioxo-octahydroxanthenes was described by Knoevenagel condensation, Michael addition and cyclodehydration of dimedone. This reaction was carried out through condensation of dimedone and various aromatic aldehydes in the presence of task-specific Brønsted acidic ionic liquid under solvent free conditions. The catalyst could be recycled five times without si...

Thia-Michael reactions between aliphatic and aromatic thiols various Michael acceptors were performed under environmentally-friendly solvent-free conditions using Amberlyst® A21 as a recyclable heterogeneous catalyst to efficiently obtain the corresponding adducts in high yields. Ethyl acrylate was main acceptor used, although others such acrylamide, linear, cyclic enones also utilized successf...

We distinguished the four alleles of OXA subgroups from 339 strains of Acinetobacter baumannii using Polymerase Chain Reaction, and investigated distributions of OXA subgroups in clinical isolated strains. A total of 196 Acinetobacter baumannii were isolated from the Central Hospital of Zhumadian between 2010 and 2014. Amplification of OXA genes, blaOXA-23, blaOXA-24, blaOXA-51 and blaOXA-58, w...

The aim of this study was to investigate the existence of a β-lactamase gene in a group of multi-drug resistant Acinetobacter baumannii. Twenty strains of multi-drug resistant A. baumannii were isolated. Thirty-four β-lactamase genes and the ISaba1-OXA-23 linkage were analyzed in these strains by polymerase chain reaction (PCR) and verified by DNA sequencing. Three kinds of β-lactamase genes (T...

INTRODUCTION Acinetobacter spp. have emerged as notorious pathogens involved in healthcare-associated infections. Carbapenems are important antimicrobial agents for treating infections due to multidrug resistant Acinetobacter spp. Different mechanisms may confer resistance to these drugs in the genus, particularly production of class D carbapenemases. OXA-23-like family has been pointed out as ...

conclusions the present study showed that bla oxa-23-like was the most frequent carbapenemase identified among carbapenem-resistant a. baumannii isolated in tehran hospitals. evaluation of antibiotic resistance genes in a. baumannii, is necessary to control further dissemination of these antibiotic resistant genes. results results showed that 123 of 131 (93.89%) acinetobacter species, possessed...

We present an isolate of Klebsiella pneumoniae OXA-48 isolated in a 68-year-old man who underwent radical prostatectomy due to prostate cancer. The antibiotic susceptibility testing to a wide range of antibiotics was performed by disk diffusion method and determination of minimal inhibitory concentrations. The isolate was classified as multidrug-resistant. It showed intermediate susceptibility ...

OBJECTIVES Acinetobacter baumannii is a significant pathogen in health care settings. In recent years, an increase in carbapenem resistance among A. baumannii due to Ambler class B metallo-beta-lactamases or class D OXA carbapenamases has been reported. In this study we detected the presence of OXA carbapenamases and coproduction of metallo-beta-lactamases (blaVIM and blaIMP ) by phenotypic and...

A novel series of 2'-oxa-3'-aza-4'a-carbanucleosides, featured with a triazole linker at the 5'-position, has been developed by exploiting a click chemistry reaction of 5'-azido-2'-oxa-3'-aza-4'a-carbanucleosides with substituted alkynes. Biological tests indicate an antitumor activity for the synthesized compounds: most of them inhibit cell proliferation of Vero, BS-C-1, HEp-2, MDCK, and HFF c...