Results 81 to 90 of about 5,810 (212)

Cycloaddition of Benzyne with Alkoxy-Substituted Pyrroline-N-oxides­: Unexpected Rearrangement to an N-Phenylpyrrole

SynOpen, 2018
Reaction of enantiopure 3,4-dialkoxy-pyrroline N-oxides with benzyne affords the expected tetrahydrobenzo[d]pyrrolo[1,2-b]isoxazoles along with an unexpected 2,3-disubstitued-N-phenyl-pyrrole derived from an unprecedented rearrangement of the adduct of ...
Franca M. Cordero, Bhushan B. Khairnar, Anna Ranzenigo, Alberto Brandi   +3 more
doaj   +1 more source

Synthesis of (4-Trifluoromethyl)isoxazoles through a Tandem Trifluoromethyloximation/Cyclization/Elimination Reaction of α,β-Unsaturated Carbonyls

We disclose a metal-free, cascade regio- and stereoselective trifluormethyloximation, cyclization, and elimination strategy with readily available α,β-unsaturated carbonyl compounds to access a wide variety of pharmaceutically potential heteroaromatics ...
Paramita Pattanayak (14784916), Tanmay Chatterjee (1554559)   +1 more
core   +1 more source

Synthesis of Isoxazoles via Electrophilic Cyclization

, 2016
A variety of 3,5-disubstituted 4-halo(seleno)isoxazoles are readily prepared in good to excellent yields under mild reaction conditions by the reaction of 2-alkyn-1-one O-methyl oximes with ICl, I2, Br2, or ...
Richard C. Larock (1353099), Jesse P. Waldo (1960012)   +1 more
core   +1 more source

Molecular Structure of Heterocycles: 6. Solvent Effects on the 17O Nmr Chemical Shifts of 5-Trichloromethylisoxazoles

Journal of the Brazilian Chemical Society, 2001
A multilinear-regression analysis using the Kamlet-Abboud-Taft (KAT) solvatochromic parameters in order to elucidate and quantify the solvent effects on the 17O chemical shifts of three 5-trichloromethylisoxazoles [(1a) non-, (1b) 3-methyl- and (1c) 4 ...
Martins Marcos A. P., Freitag Rogério A., Zimmermanna Nilo E. K., Sinhorin Adilson P., Cúnico Wilson, Bastos Giovani P., Zanatta Nilo, Bonacorso Helio G.   +7 more
doaj  

Development of new methodologies towards the synthesis of functionalized heterocyclic isoxazolidines, isoxazoles and [1,2,4] triazoles

, 2014
This thesis describes our attempts towards the development of new methodologies for the synthesis of heterocyclic functionalized isoxazolidines, isoxazoles and [1,2,4] triazolopiperazines.
Zhu, Di
core  

Versatile and Efficient Solid-Phase Syntheses of Pyrazoles and Isoxazoles

, 2016
Condensation of aromatic or aliphatic esters with resin-supported acetyl carboxylic acids 2, followed by cyclization with hydrazines or hydroxylamine, activation of the linker, and cleavage using amines provides highly substituted, isomeric pyrazoles or ...
Min Shu (261988), Kevin T. Chapman (2404213), Dong-Ming Shen (523843)   +2 more
core   +1 more source

Synthesis of 3,5-Disubstituted Isoxazoles via Cope-Type Hydroamination of 1,3-Dialkynes

, 2016
An efficient method for the synthesis of 3,5-disubstituted isoxazoles is described. The reactions of 1,3-dialkynes with hydroxylamine proceeded smoothly in DMSO under mild reaction conditions to produce 3,5-disubstituted isoxazoles in satisfactory to ...
Xiaoqiang Yu (128293), Xiujuan Feng (1617112), Ming Bao (1617106), Liangguang Wang (1991797)   +3 more
core   +1 more source

Synthesis of 3-Acyl-4-quinolones via Reductive Ring Transformation of 4-(2-Nitrobenzoyl)isoxazoles

Compounds
4-(2-Nitrobenzoyl)isoxazoles are readily available from 3,5-disubstituted 4-iodoisoxazoles through iodine–lithium exchange and trapping with 2-nitrobenzaldeyde, followed by Jones oxidation of the obtained secondary alcohols. Reductive ring transformation
Pavlos Pelagias, Jan P. Sandler, Franz Bracher   +2 more
doaj   +1 more source

Sugar Isoxazole Conjugate Synthesis via Glucose С(З) Modification

Modification of С(З) position in glucose leads to discovery of new previously unknown isoxazole sugar conjugates. As а starting material we hаvе used inexpensive diacetone-D-glucose and have transformed it to the isoxazoles containing ...
Lugiņina, Jevgeņija, Beļakovs, Sergejs, Turks, Māris, Rjabovs, Vitālijs   +3 more
core  

Electrochemical and yeast-catalysed ring-opening of isoxazoles in the synthesis of analogues of the herbicide Grasp(R)

, 2001
Isoxazoles substituted with an electron-withdrawing group at the 4-position undergo electrochemical and yeast-catalysed N-O bond cleavage. The electrolysis is much more efficient and, with acyl- and alkoxycarbonyl-substituted isoxazoles, it affords the ...
Easton, Christopher J., Lee, Connie K. Y., Heath, Graham A., Simpson, George W., Tiekink, Edward Richard Tom, Hughes, Christine Merricc M., Vuckovic, George J., Savage, G. Paul, Webster, Richard D., Richard D. Webster, Gregory W. Simpson, George J. Vuckovic, Graham A. Heath, Connie K. Y. Lee, Edward R. T. Tiekink, Christopher J. Easton, C. Merrîcc M. Hughes, G. Paul Savage   +17 more
core   +1 more source