Results 231 to 240 of about 8,940 (287)

Synthesis of 3-Acyl-isoxazoles and Δ2-Isoxazolines from Methyl Ketones, Alkynes or Alkenes, and tert-Butyl Nitrite via a Csp3-H Radical Functionalization/Cycloaddition Cascade.

Organic Letters, 2019
A novel metal-free tandem Csp3-H bond functionalization of ketones and 1,3-dipolar cycloaddition has been developed. An efficient approach to a variety of oxazole and isoxazoline derivatives is demonstrated using the 1,3-dipolar cycloaddition of alkynes ...
P. Dai, Xin Tan, Qian Luo, Xiang Yu, Shuguang Zhang, Fang Liu, Weihua Zhang   +6 more
semanticscholar   +1 more source

Synthesis of isoxazolines by the electrophilic chalcogenation of β,γ-unsaturated oximes: fishing novel anti-inflammatory agents.

Journal of Organic Chemistry, 2019
We describe herein a new strategy to prepare chalcogen-functionalized isoxazolines. The strategy involves the reaction of β,γ-unsaturated oximes with electrophilic selenium and tellurium species, affording 19 new selenium- and tellurium-containing ...
E. F. Lopes, Filipe Penteado, S. Thurow, M. Pinz, Angélica S. Reis, E. A. Wilhelm, C. Luchese, Thiago Barcellos, B. Dalberto, Diego Alves, M. S. da Silva, E. Lenardão   +11 more
semanticscholar   +1 more source

Asymmetric synthesis of chiral spiro bis(isoxazoline) and spiro (isoxazole–isoxazoline) ligands

Tetrahedron: Asymmetry, 2010
Abstract Asymmetric synthesis of novel chiral ligands, bis(isoxazoline) on a spiro[4.4]nonane scaffold and isoxazole–isoxazoline on a spiro[4.5]decane scaffold, has been achieved by utilizing an enantiomerically pure alcohol as the starting material.
Toyohiro Nagano, Hiroaki Sasai, Kazuhiro Takenaka, Shinobu Takizawa   +3 more
openaire   +2 more sources

ChemInform Abstract: Oxidative Conversion of Isoxazolidines to Isoxazolines.

ChemInform, 1998
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
and Lihong Sun, Hung-Jang Gi, Kang Zhao, Pan Li   +3 more
openaire   +3 more sources

Steroidal isoxazoles, isoxazolines and isoxazolidines [PDF]

Journal of Heterocyclic Chemistry, 1998
AbstractThe present review considers new useful heterocyclosteroids which contain five‐membered heterocyclic systems, namely, isoxazoles, isoxazolines and isoxazolidines, condensed to the cyclopentanoperhy‐drophenanthrene skeleton, in different positions of the molecule, with changes in their physiological activity and the appearance of new interesting
Sotiris S. Nikolaropoulos, Ch. Camoutsis
openaire   +2 more sources

Conversion of 2-isoxazolines to isoxazoles

Tetrahedron, 1965
Abstract A convenient and easy conversion of 2-isoxazolines to isoxazoles is described. The reaction proceeds via N-bromosuccinimide bromination and subsequent dehydrobromination with bases, and has considerable application both to alkyl- and aryl-mono and and 3,5-disubsituted 2-isoxazolines.
G. Bianchi, Paolo Grünanger
openaire   +2 more sources

TBHP-Induced Iodocyclization with I2: Atom Economic Synthesis of Iodinated Isoxazolines in Water under Mild Conditions

ACS Sustainable Chemistry and Engineering, 2019
An efficient intramolecular iodooxygenation of unsaturated ketoximes has been achieved through the activation of iodine by TBHP, yielding various types of synthetically versatile iodinated isoxazolines.
Xiaoqing Li, Xinqiang Wang, Zhi Wang, Xinhuan Yan, Xiangsheng Xu   +4 more
semanticscholar   +1 more source

Metal-free oxysulfonylation and aminosulfonylation of alkenyl oximes: synthesis of sulfonylated isoxazolines and cyclic nitrones.

Organic and biomolecular chemistry, 2019
Intramolecular oxysulfonylation of alkenyl oximes was reported. Using iodine as the catalyst, TBHP as the oxidant, and sulfonyl hydrazides as the sulfonyl radical source, a variety of sulfonylated isoxazolines were obtained in moderate to excellent ...
Zhong-Qi Xu, Lin-Chuang Zheng, Lin Li, Lili Duan, Yue‐Ming Li   +4 more
semanticscholar   +1 more source

Structure and stability of isoxazoline compounds [PDF]

Russian Journal of General Chemistry, 2013
Structure of isoxazoline compounds formed via the reaction of alkyl-substituted benzonitrile oxides with ethylene was determined by X-ray diffraction method. Isoxazoline ring is flattened, the bond lengths in it depend slightly on the nature of substituents (CH3, C2H5) and their position in the benzene ring and the angle of rotation relative to the ...
T. K. Goncharov, Z. G. Aliev, Sergey M. Aldoshin, V. V. Dubikhin, E. L. Ignat’eva, G. M. Nazin   +5 more
openaire   +1 more source

ChemInform Abstract: Highly Effective Dehydrogenation of Steroidal Isoxazolines. [PDF]

ChemInform, 1990
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
R. P. Litvinovskaya, A. V. Baranovskii, Vladimir A. Khripach   +2 more
openaire   +2 more sources