Results 171 to 180 of about 4,154 (224)

Facile synthesis of spirooxindole-pyrazolines and spirobenzofuranone-pyrazolines and their fungicidal activity

Organic & Biomolecular Chemistry, 2015
A new and facile synthetic method is developed for biologically important spirooxindole-pyrazolines and spirobenzofuranone-pyrazolines.
Changjiang, Yang, Juanjuan, Li, Rong, Zhou, Xiangyu, Chen, Yunpeng, Gao, Zhengjie, He   +5 more
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Preparation of the simplest ?1-pyrazolines by isomerization of ?2-pyrazolines

Chemistry of Heterocyclic Compounds, 1971
Δ2-Pyrazolines that do not have substituants in the 1- and 3-positions are not capable of isomerization to 3-substituted pyrazolines and can be converted to Δ1-pyrazolines by slow distillation in the presence of bases. This method, which is completely analogous to the synthesis of azo compounds from alkylhydrazones, gives good results when applied to 4-
B. V. Ioffe, N. B. Burmanova
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Steroidal pyrazolines

Journal of Heterocyclic Chemistry, 1978
AbstractReaction of 21‐benzal‐5‐pregnen‐3β‐ol‐20‐one acetate with phenylhydrazine or p‐methoxy‐phenylhydrazine in the presence of hydrochloric acid yielded 3β‐aeetoxy‐1′,5′ ‐diphenyl‐5‐preg‐neno[20,21‐c]pyrazoline. Alkaline hydrolysis of the 3β‐acetoxy group followed by Oppenauer oxidation furnished the 3‐oxo‐1′,5′‐diphenyl‐4‐pregneno[20, 21‐c ...
Panayotis Catsoulacos, C. I. Stassinopoulou   +1 more
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A Pyrazoline Derivative of Eunicin Acetate

Acta Crystallographica Section C Crystal Structure Communications, 1996
The present crystal structure determination established spiro [¿3a,4,5,6,7,8,11,12,13,14,15,15a-dodecahydro-6,10,14-trimet hyl-2-oxo-5, 15-epoxy-3H-cyclotetradeca-[b]furan¿-3,3'-1'-pyrazoline]-6-yl acetate, C23H34N2O5, as a pyrazoline derivative of eunicin acetate.
S, Khalil, M B, Hossain, D, van der Helm, M, Alam, R, Sanduja   +4 more
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TBD-organocatalysed synthesis of pyrazolines

Organic & Biomolecular Chemistry, 2009
It was found that TBD, a cheap and commercially available guanidine, easily catalysed the synthesis of biologically important 3,5-diarylpyrazolines from chalcones and acylhydrazines via a selective secondary amine alkylation.
Mahé, Olivier, Frath, Denis, Dez, Isabelle, Marsais, Francis, Levacher, Vincent, Brière, Jean-François   +5 more
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On the stereochemistry of pyrazolines: 1-Acetyl-3,5-disubstituted pyrazolines-2

Journal of Organometallic Chemistry, 1984
Abstract The geometries of the molecules of the isomeric N -acetyl derivatives of 3-ferrocenyl-5- p -bromophenyl- and 3- p -bromophenyl-5-ferrocenylpyrazolines-2 with a chiral centre in position 5 of pyrazoline have been determined by an X-ray study.
V.G. Andrianov, Yu.T. Struchkov, V.N. Postnov, E.I. Klimova, V.A. Sazonova   +4 more
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Steroidal pyrazoline and pyrazole

Journal of Chemical & Engineering Data, 1987
Synthese des composes du titre a partir de l'acetoxy-3 pregnene-5one-20 et du pyridinecarbaldehyde ...
Charalambos Camoutsis, Sotirios Nicolaropoulos, Panayotis Catsoulacos   +2 more
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Pyrazolines. VII. Concerning the formation of olefins from the pyrolysis of pyrazolines

Canadian Journal of Chemistry, 1967
The geometrically isomeric cis- and trans-5-3-methyl-4-ethyl-3-carbomethoxy-Δ1-pyrazolines were prepared and their pyrolysis and photolysis studied. The isomeric pyrazolines gave cyclopropane products of mixed stereochemistry, but predominantly with retention of the stereochemistry present in the starting pyrazoline.
Donald E. McGreer, Weh-Sai Wu
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Pyrazolines X. Kinetics for the pyrolysis of some deuterated 1-pyrazolines in solution

Canadian Journal of Chemistry, 1969
The kinetics and product distribution have been measured for the pyrolysis of 3-methyl-3-carbo-methoxy-1-pyrazoline (1) and its 4,4-d2 and 5,5-d2 analogues in tetralin, n-butyl phthalate, nitrobenzene, and formamide. The isotope effect kH/kD for 1-5,5-d2 of 1.22 and for 1-4,4-d2 of 1.36 is consistent with a mechanism involving migration of the C-4 ...
Donald E. McGreer, Ian M. E. Masters
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Synthesis of the Steroidal Pyrazolines.

ChemInform, 2004
AbstractFor Abstract see ChemInform Abstract in Full Text.
Shamsuzzaman Shamsuzzaman, Nazish Siddiqui   +1 more
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