Results 1 to 10 of about 13,633 (275)

Expedient Organocatalytic Syntheses of 4-Substituted Pyrazolidines and Isoxazolidines [PDF]

Molecules, 2016
The efficient organocatalytic synthesis of heterocyclic systems of biological relevance is a subject of growing interest. We have found that the pyrrolidine/benzoic acid-catalyzed reaction of α-substituted propenals such as methacrolein, 2-benzylpropenal
Tarek Yousfi, Alysha Elliott, Messiad Hanane, Rachid Merdes, Albert Moyano   +4 more
doaj   +2 more sources

Trifluoroethanol-assisted asymmetric propargylic hydrazination to α-tertiary ethynylhydrazines enabled by sterically confined pyridinebisoxazolines [PDF]

Nature Communications
We report the highly enantioselective Cu-catalyzed asymmetric propargylic substitution (APS) of α-tertiary propargylic electrophiles using hydrazines and hydroxylamines as a fruitful strategy to access multifunctional α-tertiary hydrazines or ...
Yi Gong, Zheng Zhang, Huijuan Liu, Tao Wang, Mengmeng Jiang, Nan Feng, Peiying Peng, Huimin Wang, Feng Zhou, Xin Wang, Jian Zhou   +10 more
doaj   +2 more sources

Copper-catalysed enantioconvergent N-alkylation of hydrazines with racemic α-haloamides to access enantioenriched hydrazines [PDF]

Nature Communications
Chiral hydrazines are important building blocks in chiral drug molecules, N-amino peptides, and aza-heterocycles. The catalytic enantioconvergent N-alkylation of readily available hydrazine derivatives with various racemic alkyl halides offers a highly ...
Nan Li, Sheng-Yu He, Peng-Fei Wang, Qiang-Shuai Gu, Zhong-Liang Li, Ji-Jun Chen, Xin-Yuan Liu   +6 more
doaj   +2 more sources

Chemoselective synthesis of 1,3,4-thiadiazoles from acyl hydrazines and nitroalkanes using elemental sulfur [PDF]

Nature Communications
Substituted 1,3,4-thiadiazoles find extensive use in pharmaceutical, agricultural, and materials chemistry. The incorporation of adaptable heterocyclic pharmacophores results in tunable hybrid molecules with diverse medicinal properties.
Xiaonan Wang, Xiuwen Yu, Ruixi Qian, Silong Xu, Martin J. Lear, Wangxiao He, Jing Li   +6 more
doaj   +2 more sources

Direct Cyclization/Chlorination Strategy of Hydrazines for Synthesis of 4-Chloropyrazoles by TCCA [PDF]

Molecules
A new method for synthesis of various 4-chloropyrazoles through the direct cyclization/chlorination of hydrazines by using 1,3,5-trichloroisocyanuric acid (TCCA) as both oxidant and chlorinating agent under mild conditions has been proposed. Based on the
Qingfu Deng, Chenglong Ma, Liangzhen Hu, Yan Xiong   +3 more
doaj   +2 more sources

Synthesis of 1,2,3-triazoles containing an allomaltol moiety from substituted pyrano[2,3-d]isoxazolones via base-promoted Boulton–Katritzky rearrangement [PDF]

Beilstein Journal of Organic Chemistry
For the first time, the interaction of aroyl containing pyrano[2,3-d]isoxazolone derivatives with various hydrazines was studied. It was shown that the considered process includes formation of corresponding hydrazones followed by Boulton–Katritzky ...
Constantine V. Milyutin, Andrey N. Komogortsev, Boris V. Lichitsky   +2 more
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Synthesis and Characterization of Novel Methyl (3)5-(N-Boc-piperidinyl)-1H-pyrazole-4-carboxylates

Molecules, 2021
Series of methyl 3- and 5-(N-Boc-piperidinyl)-1H-pyrazole-4-carboxylates were developed and regioselectively synthesized as novel heterocyclic amino acids in their N-Boc protected ester form for achiral and chiral building blocks.
Gita Matulevičiūtė, Eglė Arbačiauskienė, Neringa Kleizienė, Vilija Kederienė, Greta Ragaitė, Miglė Dagilienė, Aurimas Bieliauskas, Vaida Milišiūnaitė, Frank A. Sløk, Algirdas Šačkus   +9 more
doaj   +1 more source

Regioselective Synthesis of 5- and 3-Hydroxy-N-Aryl-1H-Pyrazole-4-Carboxylates and Their Evaluation as Inhibitors of Plasmodium falciparum Dihydroorotate Dehydrogenase

Molecules, 2022
In silico evaluation of various regioisomeric 5- and 3-hydroxy-substituted alkyl 1-aryl-1H-pyrazole-4-carboxylates and their acyclic precursors yielded promising results with respect to their binding in the active site of dihydroorotate dehydrogenase of ...
Luka Vah, Tadej Medved, Uroš Grošelj, Marina Klemenčič, Črtomir Podlipnik, Bogdan Štefane, Jernej Wagger, Marko Novinec, Jurij Svete   +8 more
doaj   +1 more source

Copper-Catalyzed One-Pot Synthesis of N-Sulfonyl Amidines from Sulfonyl Hydrazine, Terminal Alkynes and Sulfonyl Azides

Molecules, 2021
N-Sulfonyl amidines are developed from a Cu-catalyzed three-component reaction from sulfonyl hydrazines, terminal alkynes and sulfonyl azides in toluene at room temperature.
Yu Zhao, Zitong Zhou, Man Chen, Weiguang Yang   +3 more
doaj   +1 more source

Organic solvent-free synthesis of sulfonyl hydrazides in water

Tetrahedron Green Chem, 2023
An organic solvent-free synthesis of sulfonyl hydrazides has been achieved in water. The reactions of equimolar amount of sulfonyl chlorides and hydrazines afforded a series of substituted sulfonyl hydrazides at 60 ​°C for 1 ​h in water as a solvent in ...
Shizuki Noda, Shinji Tanimori
doaj   +1 more source