1,3-Dibromo-5,5-dimethylhydantoin (DBH), as a cheap and commercially available reagent, is efficiently able to catalyze the synthesis of polyhydroquinoline derivatives and 12-aryl-8,9,10,12-tetrahydro[a] xanthene-11-ones via one-pot multi-component reactions. This novel synthetic method has the advantages of low cost and availability of the catalyst, short reaction times, high to excellent yiel...

an efficient and eco-friendly protocol for the preparation of 2-amino-4h-chromenes employing a multi-component, one-pot condensation reaction between aromatic aldehydes, malononitrile and1-naphthol has been developed. the reaction of 1-naphthol with malononitrile and various aromatic aldehydes was carried out in water-ethanol (1:1) at reflux using 20 mol% of diammonium hydrogen phosphate as cat...

We find a family of exact solutions to the semi-classical equations (including back-reaction) of two-dimensional dilaton gravity, describing infalling null matter that becomes outgoing and returns to infinity without forming a black hole. When a black hole almost forms, the radiation reaching infinity in advance of the original outgoing null matter has the properties of Hawking radiation. The r...

Macromomycin (MCR), an unique membrane-reactive anticancer antibiotic, was incubated with murine monoclonal anti-HLA IgG1 antibody (H-1) in the presence of carbodiimide. The resulting mixture was fractionated with a Sephadex G-200 column. The first and second fractions were shown to contain MCR-(H-1) conjugate by the elution profile, as well as by the Sarcina lutea growth inhibition assay and O...

A novel magnetically immobilized polyethyleneimine (PEI)fabricated by covalently anchoring on MCM-41 (MCM-41@PEI)was prepared. The synthesized catalyst was characterized by Fouriertransform infrared (FT-IR), thermogravimetric analysis (TGA), X-raypowder diffraction (XRD), scanning electron microscopy (SEM) andtransmission electron microscopy (TEM). The immobilized PEI wasshown to be an efficien...

The plasmid-borne colistin-resistant gene mcr-1 has rapidly become a worldwide public health concern. This study aims to determine the host bacterial strains, plasmids, and genetic contexts of mcr-1 in hospital sewage. A 1-ml hospital sewage sample was cultured. Colistin-resistant bacterial colonies were selected on agar plates and were subjected to whole genome sequencing and subsequent analys...

An efficient, recyclable and environmental-friendly synthetic route to polyhdroquinoline derivatives have been developed via multi-component one-pot Hantzsch reaction of various aromatic aldehyde, 2 equivalents of 5,5-dimethyl-1,3-cyclohexanedione (dimedone), ethyl acetoacetate and ammonium acetate using nano magnesium oxide as a catalyst in ethanol under reflux condition. Reaction with 4-chlor...

the highly substituted pyridine derivatives are found to exhibit diverse pharmacological activities. they are also emerged as potential medicinal leads in developing therapeutic agents for the treatment of various diseases. in this work, a series of 2-amino-3,5-dicarbonitrile-6-thio-pyridine derivatives have been synthesized at room temperature via one-pot, multi-component reaction of various a...

A simple and efficient procedure for the synthesis of 2-amino-3-cyanopyridines from aldehydes, ketones, malononitrile, and ammonium acetate via one-pot reaction is reported. Zinc zirconium phosphate (ZPZn) nanoparticles were used as a convenient and efficient catalyst for this multicomponent reaction (MCR) under solvent-free conditions, and fair to excellent yields were achieved. The catalyst w...

The mobile colistin resistance gene mcr-1 has attracted global attention, as it heralds the breach of polymyxins, one of the last-resort antibiotics for the treatment of severe clinical infections caused by multidrug-resistant Gram-negative bacteria. To date, six slightly different variants of mcr-1, and a second mobile colistin resistance gene, mcr-2, have been reported or annotated in the Gen...