Results 21 to 30 of about 7,470 (229)
One-step synthesis of differently bis-functionalized isoxazoles by cycloaddition of carbamoylnitrile oxide with β-keto esters [PDF]
, 2012 A new protocol for synthesizing different functionalized isoxazoles is provided. Carbamoylnitrile oxide generated from nitroisoxazolone underwent inverse electron-demand 1,3-dipolar cycloaddition with 1,3-dicarbonyl compounds in the presence of magnesium
975 +15 more
core +1 more source
Molecules, 2022 Amides, anhydrides, esters, and thioesters of 2H-azirine-2-carboxylic acids were prepared by a rapid procedure at room temperature involving FeCl2-catalyzed isomerization of 5-chloroisoxazoles to 2H-azirine-2-carbonyl chlorides, followed by reaction with
Anastasiya V. Agafonova +2 more
doaj +1 more source
Organics, 2021 Conjugated azapolyenes (azabuta-1,3-dienes, aza-/diaza-/oxaza-/oxadiazahexa-1,3,5-trienes) are highly reactive in electrocyclization reactions, which makes them convenient precursors for the synthesis of a wide range of four-, five-, and six-membered ...
Nikolai V. Rostovskii +2 more
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Chalcones as versatile synthons for the synthesis of 5- and 6-membered nitrogen heterocylces [PDF]
, 2014 Chalcones belong to the flavonoid family which constitutes one of the major classes of naturally occurring oxygen heterocyclic compounds. The alpha,beta-unsaturated carbonyl system of chalcones possesses two electrophilic reactive centers allowing them ...
Albuquerque, Hélio +3 more
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Angewandte Chemie, EarlyView.The vanadium‐dependent haloperoxidase (VHPO) class of enzymes has been shown to catalyze cryptic nitrile oxide generation in an oxidative [3+2] cycloaddition reaction between aldoximes and alkenes to generate isoxazolines. This biotechnology has been applied to a chemoenzymatic sequence starting from aldehydes through in situ condensation with ...
Manik Sharma, Kyle F. Biegasiewicz
wiley +2 more sources
Isoxazole derivatives as new nitric oxide elicitors in plants
Beilstein Journal of Organic Chemistry, 2017 Several 3,5-disubstituted isoxazoles were obtained in good yields by regiospecific 1,3-dipolar cycloaddition reactions between aromatic nitrile oxides, generated in situ from the corresponding hydroxyimidoyl chlorides, with non-symmetrical activated ...
Anca Oancea +9 more
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Solvent‐Induced Covalent Bond Softening Boosts Battery Voltage
Angewandte Chemie, EarlyView.The strong attractive interaction between the nucleophilic center of the solvent and the electrophilic region of the covalently bonded cathode fragment triggers charge transfer. This results in the electron population in the antibonding orbital of the covalent bond, leading to bond weakening and elongation, and consequently increasing the cathode ...
Yanyan Wang +6 more
wiley +2 more sources
Zanco Journal of Medical Sciences, 2023 Background and objective: Five-membered heterocycle compounds having single oxygen and nitrogen atom at adjacent positions are known as isoxazoles. Isoxazole compounds have a broad range of biological activities and therapeutic value.
Sarbast M. Ahmed +4 more
doaj
Ruthenium-catalyzed asymmetric reduction of isoxazolium salts : access to optically active Δ4-isoxazolines [PDF]
, 2018 A tethered MsDPEN–ruthenium catalyst reduces a series of isoxazolium salts, affording optically active Δ4-isoxazolines in moderate to good yields and enantioenrichment. The redundancy of heating or high pressures allowed for chemoselective reduction with
Chew, Renta Jonathan, Wills, Martin
core +1 more source
Beilstein Journal of Organic Chemistry, 2011 The first photocycloadditions of aromatic and aliphatic aldehydes to methylated isoxazoles are reported. The reactions lead solely to the exo-adducts with high regio- and diastereoselectivities. Ring methylation of the isoxazole substrates is crucial for
Axel G. Griesbeck +3 more
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