Results 31 to 40 of about 950 (182)
Synthesis and tautomerism of spiro-pyrazolines [PDF]
Tetrahedron Letters, 2014 An experimental study on the synthesis, tautomerism and acid promoted structural changes of spiro-pyrazolines is described. The target was achieved through a [3+2]-dipolar cycloaddition of an alkene with nitrile imines generated in situ and was isolated in high yield.
Sureshbabu, Dadiboyena +2 more
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Journal of Saudi Chemical Society, 2016 A series of 1-thiocarbamoyl-3-phenyl-5-hydroxy-5-(2-pyridyl)-4-pyrazolines derivatives have been synthesized using sodium acetate as a catalyst. The spectral characterization and structure of 1-thiocarbamoyl-3-phenyl-5-hydroxy-5-(2-pyridyl)-4-pyrazolines
D. Chinnaraja +3 more
doaj +1 more source
Synthesis and Pharmacological Evaluation of Some Phenylpyrazolo Indoquinoxaline Derivatives
E-Journal of Chemistry, 2011 Indoloquinoxalin was fused with 2,3 diphenyl quinoxaline by a methylene bridge which was then allowed for acetylation. The acetylated product was made to react with different aromatic aldehydes to give chalcones.
CH. Sridevi, K. Balaji, A. Naidu
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Synthesis of Non-Racemic Pyrazolines and Pyrazolidines by [3+2] Cycloadditions of Azomethine Imines
Molecules, 2017 Asymmetric [3+2] cycloadditions of azomethine imines comprise a useful synthetic tool for the construction of pyrazole derivatives with a variable degree of saturation and up to three stereogenic centers.
Franc Požgan +4 more
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Indonesian Journal of Chemistry, 2022 Two series of new 3,5-disubstituted-pyrazole-1-carbothioamides (4a-f and 5a-e) were designed and synthesized through condensation reaction between chalcones and thiosemicarbazides under alkaline condition via cyclocondensation reaction.
Kok Tong Wong +6 more
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Acta Crystallographica Section E: Crystallographic Communications, 2019 In the title pyrazoline derivative, C16H16N2O3·H2O, the pyrazoline ring has an envelope conformation with the substituted sp2 C atom on the flap. The pyrazoline ring makes angles of 86.73 (12) and 13.44 (12)° with the trisubstituted and disubstituted ...
Linh Duong Khanh +5 more
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THE TAUTOMERISM OF PYRAZOLINES (DIHYDROPYRAZOLES) [PDF]
Journal of the Chilean Chemical Society, 2015 The exception to the rule that Δ3-pyrazolines are not stable unless both nitrogen atoms are substituted that has been recently published, Tetrahedron Lett. 55, 2208, (2014), has been proved false. By means of GIAO/B3LYP/6-311++G(d,p) calculations, it has been shown that the product is a pyrazole formed by rearrangement.
ALKORTA, I, ELGUERO, J
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Synthesis of Some New Pyrazolines [PDF]
مجلة التربية والعلم, 2006 The present work includes the preparation of a series of substituted chalcones ( NO2 , Me , OMe , Cl ) and condensation of these chalcone with a series of prepared aromatic and aliphatic acid hydrazides in a basic medium to afford the new pyrazolines ...
A.J. AL-Hamdany, A.M. Hamdy
doaj +1 more source
Bulletin of the Chemical Society of Ethiopia, 2014 Some aryl-aryl 1H pyrazoles have been synthesised by cyclization of aryl chalcones and hydrazine hydrate in the presence of SOCl2. The yields of the pyrazoles are more than 85%.
K. Ranganathan +5 more
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Synthesis of enones, pyrazolines and pyrrolines with gem-difluoroalkyl side chains
Beilstein Journal of Organic Chemistry, 2013 Starting from easily accessible gem-difluoropropargylic derivatives, a DBU-mediated isomerisation affords enones in fair yields with a gem-difluoroalkyl chain.
Assaad Nasr El Dine +8 more
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