نتایج جستجو برای: substituted nitrile oxide

تعداد نتایج: 216363  

Journal: :Chemical communications 2008
Justin R Denton Kevin Cheng Huw M L Davies

Nitrile-substituted cyclopropanes are readily synthesized in a stereocontrolled fashion from the intermolecular cyclopropanation between 2-diazo-2-phenylacetonitrile and electron-rich olefins, catalyzed by the chiral dirhodium complex, Rh(2)(S-PTAD)(4).

Journal: :Organic & biomolecular chemistry 2010
Christian Spiteri Christopher Mason Fengzhi Zhang Dougal J Ritson Pallavi Sharma Steve Keeling John E Moses

An efficient protocol for the synthesis of a range of 1,2-benzisoxazoles using an improved 1,3-dipolar cycloaddition of nitrile oxides and benzyne is described. Key to the procedure is the in situ generation of the reactive nitrile oxide and benzyne reactants simultaneously.

Journal: :Biochemical pharmacology 1994
T E Renau J S Lee H Kim C G Young L L Wotring L B Townsend J C Drach

Non-nucleoside analogs of the pyrrolopyrimidine nucleosides toyocamycin, sangivamycin and thiosangivamycin have been synthesized and their cytotoxicity in mammalian cells determined. While studying the effects of 5-thioamide-substituted analogs on cell growth, we observed an interesting phenomenon in which cells recovered spontaneously from growth inhibition during extended incubations. HPLC st...

Journal: :Steroids 2014
Gergő Mótyán Zalán Kádár Dóra Kovács János Wölfling Éva Frank

Novel 5α-androstanes containing an isoxazoline moiety condensed to ring A or D were efficiently synthetized by 1,3-dipolar cycloadditions of aryl nitrile oxides to steroidal α,β-unsaturated ketones. During the ring closures, regioisomers in which the O terminus of the nitrile oxide dipoles is attached to the β-carbon of the dipolarophile were formed in a stereoselective manner to furnish exclus...

Journal: :Organic & biomolecular chemistry 2011
Shravankumar Kankala Ravinder Vadde Chandra Sekhar Vasam

A first example of organo-N-heterocyclic carbene (NHC) catalyzed click-type fast 1,3-dipolar cycloaddition of nitrile oxides with alkynes was developed for the regioselective synthesis of 3,5-di- and 3,4,5-trisubstituted isoxazoles. Triethylamine (Et(3)N) was employed as an effective base to generate both nitrile oxide and the organo-NHC catalyst in situ. This catalytic approach was used to att...

Journal: :Chemical communications 2010
Christian Spiteri Pallavi Sharma Fengzhi Zhang Simon J F Macdonald Steve Keeling John E Moses

An efficient synthesis of a range of 1,2-benzisoxazoles using an improved 1,3-dipolar cycloaddition of nitrile oxides and benzyne is described. Key to the procedure is the in situ generation of the reactive nitrile oxide and benzyne reaction partners mediated by TBAF. Reactions are complete within 30 s, giving the target products in good to excellent yield.

Journal: :Organic & biomolecular chemistry 2012
Kirstin Scherlach Nicole Brendel Keishi Ishida Hans-Martin Dahse Christian Hertweck

Through metabolic profiling of mutants and wild type of the endofungal bacterium Burkholderia rhizoxinica two novel rhizoxin derivatives with unusual nitrile substitutions were discovered. The nitrile groups result from a photochemical oxidative cleavage of the oxazolyl moiety. In vitro studies revealed that the photooxidation by singlet oxygen also takes place in the absence of a photosensitiz...

Journal: :Organic & biomolecular chemistry 2008
David R Kelly Simon C Baker David S King Deepa S de Silva Gwyn Lord Jason P Taylor

During studies directed towards the discovery of nitrile hydrolysing enzymes from thermophiles, vanillin aldoxime was incubated with the thermophilic organism, Geobacillus sp. DDS012 isolated from Italian rye grass (Lolium multiflorum) silage. The predominant product was a dihydro-dimer, which could only be characterised by LC-MS. This was initially imagined to be the product of cycloaddition o...

Journal: :Advances in biochemical engineering/biotechnology 2009
Jing Chen Ren-Chao Zheng Yu-Guo Zheng Yin-Chu Shen

Biotransformation of nitriles mediated by nitrile-amide converting enzymes has attracted considerable attention and developed tremendously in the recent years in China since it offers a valuable alternative to traditional chemical reaction which requires harsh conditions. As a result, an upsurge of these promising enzymes (including nitrile hydratase, nitrilase and amidase) has been taking plac...

Journal: :Angewandte Chemie 2021

The direct synthesis of nitrile from N2 under mild conditions is great importance and has attracted much interest. Herein, we report a conversion into via nitrile–alkyne cross-metathesis (NACM) process involving N2-derived Mo nitride. Treatment the nitride with alkyne in presence KOTf afforded an alkyne-coordinated nitride, which was then transformed MoV carbyne corresponding upon 1 e? oxidatio...

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