نتایج جستجو برای: β-lactams

تعداد نتایج: 181273  

Fifteen novel β-lactams bearing the N-ethyl tert-butyl carbamate group 5a-o and fifteen N-(2-aminoethyl) β-lactams 6a-o were synthesized by the ketene-imine [2+2] cycloaddition reaction (Staudinger ). The cycloaddition reaction was found to be totally diastereoselective leading exclusively to the formation of the cis-β-lactam derivatives. These newly synthesized β-lactams were evaluated for the...

Fifteen novel β-lactams bearing the N-ethyl tert-butyl carbamate group 5a-o and fifteen N-(2-aminoethyl) β-lactams 6a-o were synthesized by the ketene-imine [2+2] cycloaddition reaction (Staudinger ). The cycloaddition reaction was found to be totally diastereoselective leading exclusively to the formation of the cis-β-lactam derivatives. These newly synthesized β-lactams were evaluated for the...

Journal: :iranian journal of pathology 2016
fatemeh rezaei horieh saderi shahram boroumandi soghrat faghihzadeh

background: in order to select a better antibiotic choice for treatment of pseudomonas aeruginosa infections, this study was conducted to determine the frequency of resistance to some antipseudomonal β-lactams in p. aeruginosa isolates from patients in tehran, iran. in addition, the relation between presence of genes known to be responsible for resistance to β-lactams (ampc, mexc1,2,and mexc3,4...

Journal: :iranian journal of science and technology (sciences) 2007
a. jarrahpour

synthesis of some new monocyclic β-lactams containing a quaternary carbon center via a [2+2]cycloaddition reaction is described. the reaction of achiral diphenyl ketene with chiral aldimines derivedfrom chiral 2, 3, 4, 6-tetra-o-acetyl-β-d-galactopyranosylamine, 2, 3, 4, 6-tetra-o-acetyl-β-dglucopyranosylamine and different benzaldehydes resulted in the formation of β-lactams as singlediastereo...

2016
Hayriye Genç Ramazan Kalin Zeynep Köksal Nastaran Sadeghian Umit M. Kocyigit Mustafa Zengin İlhami Gülçin Hasan Özdemir

β-Lactams are pharmacologically important compounds because of their various biological uses, including antibiotic and so on. β-Lactams were synthesized from benzylidene-inden derivatives and acetoxyacetyl chloride. The inhibitory effect of these compounds was examined for human carbonic anhydrase I and II (hCA I, and II) and acetylcholinesterase (AChE). The results reveal that β-lactams are in...

Journal: :Journal of the American Chemical Society 2016
Masaki Hayashi Shoshana Bachman Satoshi Hashimoto Chad C Eichman Brian M Stoltz

A new strategy for catalytic enantioselective C-acylation to generate α-quaternary-substituted lactams is reported. Ni-catalyzed three-component coupling of lactam enolates, benzonitriles, and aryl halides produces β-imino lactams that then afford β-keto lactams by acid hydrolysis. Use of a readily available Mandyphos-type ligand and addition of LiBr enable the construction of quaternary stereo...

Journal: :Reviews in Medical Microbiology 2013

2017
Jinghua Wang Haiyang Xu Pan Liu Mingxian Li

The purpose of this study was to compare the relative efficacy and safety of different antibiotic drugs and recommend superior regimens in the treatment of bronchitis. With respect to the antibiotic comparisons against quinolones in terms of intention-to-treat patients, we concluded that quinolones had advantages over placebo, β-lactams, sulfonamides, and double β-lactams. Concerning treatment ...

Journal: :iranian journal of science and technology (sciences) 2015
a. jarrahpour

in this paper the synthesis of some new polyaromatic monocyclic β-lactams has been reported. these cycloadducts have been synthesized by the [2+2] ketene-imine cycloaddition reaction known as the staudinger reaction. all of the products have been fully characterized by ir, 1h-nmr, 13c-nmr, mass spectroscopy and elemental analyses. the x-ray crystal structure of a cis β-lactam has been also pres...

Journal: :Molecular medicine reports 2010
Bimal K Banik Frederick F Becker

Currently available anticancer drugs are cytotoxic to normal as well as to neoplastic cells, therefore the synthesis of β-lactams as new and novel anticancer agents is extremely significant. We previously developed synthetic methods for the preparation of β-lactams and anticancer agents resulting from polyaromatic amines. There have also been reports on the synthesis and biological evaluation o...

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