Hydrazines
Mostrando 1-12 de 17 artigos, teses e dissertações.
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1. Synthesis and Evaluation of the Fungal Activity of New Pyrazole-Carboxamides against Colletotrichum gloeosporioides
The pyrazole core has been recognized by their biological properties and included in the synthesis of modern agrochemicals. Part of these studies consists of making structural modifications to pesticides for commercial purposes to increase efficacy. In this article, we present the synthesis of four new pyrazol-4-carboxamide 8a-8d derivatives (PCD), through a
J. Braz. Chem. Soc.. Publicado em: 2020-09
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2. An Acetal Acylation Methodology for Producing Diversity of Trihalomethyl-1,3-dielectrophiles and 1,2-Azole Derivatives
A series of functionalized 1,1,1-trihalo-4-methoxy-3-alken-2-ones [CX3C(O)CR1=CROMe, where X = F or Cl; R = n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-tridecyl, (CH2)2CH=C(Me)2, (CH2)2Ph, (CH2)2-(4-HOC6H4), (CH2)2-(4-MeOC6H4), (CH2)2CO2Me, (CH2)3CO2Me, CH(SMe)CH3, CH2(2-MeOC6H4), and R1 = H, and R = H and R1 = n-decyl] were synthesized from respective
J. Braz. Chem. Soc.. Publicado em: 2020-02
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3. Oxone®-Promoted One-Pot Synthesis of 1-Aryl-4-(organylselanyl)-1H-pyrazoles
We describe herein an efficient protocol for the one-pot synthesis of 4-organylselanylpyrazoles by direct cyclocondensation and C-H bond selenylation reactions starting from hydrazines, 1,3-diketones and diorganyl diselenides promoted by Oxone®. The products were obtained through a metal catalyst free methodology, under mild conditions, in short reaction ti
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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4. FLUOROUS SUPPORTED SYNTHESIS OF PYRAZOLONE DERIVATIVES FROM ALLYLIC ALCOHOLS USING A PALLADIUM-CATALYZED STRATEGY
Ten substituted pyrazolone derivatives were easily synthesized from perfluorinated allylic alcohols, via a straightforward two steps reaction involving a Heck-coupling/isomerization reaction and subsequent condensation of hydrazines. This fluorous supported methodology, that combines a cyclo-release approach and F-SPE purification allows for the obtaining of
Quím. Nova. Publicado em: 2016-08
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5. Síntese e avaliação preliminar da atividade antinociceptiva de novas isoxazolil-aril-hidrazonas
New 2-isoxazoline aldehydes were synthesized, in good yields, from cycloadduct of the 1,3-dipolar cycloaddition reaction between endocyclic enecarbamate and carboethoxyformonitrile oxide (CEFNO). Condensation of these 2-isoxazoline aldehydes with several phenyl-hydrazines produced new isoxazolyl-aryl-hydrazones, which showed low toxicity and excellent antino
Química Nova. Publicado em: 2011
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6. ESTUDO DO COMPORTAMENTO QUÍMICO DE HETEROCICLOS TRIFLUORMETIL SUBSTITUÍDOS EM REAÇÕES COM DAST / STUDY OF THE CHEMICAL BEHAVIOR OF TRIFLUOROMETHYL SUBSTITUTED HETEROCYCLES IN REACTIONS WITH DAST
This work describes the study of the chemical behavior of trifluoromethyl substituted heterocycles as 1H-pyrazoles, 2-pyrazolines, 2H-cromenones and isoxazolines in reactions with DAST, with the aim of evaluating possible reactions in the oxygenated sites, aiming mainly the insertion of fluorine atoms in these molecules. Trifluoromethylated heterocycle precu
Publicado em: 2011
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7. Design and synthesis of 1-aroyl-2-ylidene hydrazines under conventional and microwave irradiation conditions and their cytotoxic activities
Reportamos o planejamento e síntese de 1-aroil-2-(alquenil/aril)ideno hidrazinas como moléculas hibridas derivadas do ácido mafenamico e hidrazonas substituídas. Diferentes compostos baseados nesse novo plano foram preparados com bons rendimentos. O intermediário chave, N-acilidrazina, preparado a partir do ácido mafenamico, reagiu com uma variedade de
Journal of the Brazilian Chemical Society. Publicado em: 2010
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8. Reações de 1,1,1-tricloro-4-metoxi-3-penten-2-ona com hidrazinas monosubstituídas / 1,1,1-trichloro-4-methoxy-3-penten-2-ona reaction with hydrazines
The 1,1,1-trichloro-4-methoxy-3-penten-2-ona (CCl3COCH=CHOMe) reaction with hydrazines series (RNHNH2, where R = H, Me, tert-Bu, Ph, Ph(F)5, Ph-4-NO2, CO2Me e CONH2) yield to the pyrazoles N-substituted and derivatives formation by [3 + 2] ciclocondensations reactions. These compounds formation is regioespecific, it means, termodinamically controled (excepti
Publicado em: 2005
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9. Modelo matemático de câmaras de combustão bipropelentes / Mathematical model of bipropellant combustion chambers
A mathematical model of the combustion chamber of a liquid propellant rocket was developed. The combustion process is assumed to be one-dimensional and controlled by the vaporization of the droplets, since the rates of mixture and reaction in the gaseous phase are fast in comparison to the vaporization rates of the propellants. It was considered a non unifor
Publicado em: 2004
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10. Modelo matemático de câmaras de combustão bipropelentes / Mathematical model of bipropellant combustion chambers
Desenvolveu-se um modelo matemático unidimensional de uma câmara de combustão de foguete utilizando propelentes líquidos. O processo de combustão é controlado pela vaporização das gotas, uma vez que as taxas de mistura e de reação na fase gasosa são consideradas rápidas em comparação às taxas de vaporização dos propelentes. Considerouse uma
Publicado em: 2004
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11. Estudo da reatividade de a-acil-enaminocetonas com nucleofilos capazes de formar compostos heterociclicos parte II (volume I)
The reactions of 4-(methylamine)-3-penteno-2-one with several diazoketone (RCOCN2R) yielded the a-acyl-enaminoketones ( (RRCHCO (CH3CO) C=C(CH3)NHCH3 (134, R=R=Ph; 135 R=CH3 and R=Ph e 136 R=R=CH3), in good yielded. AM1 calculations show that the COCH3 group is in the plane of the molecule and thus conjugated with the double bond, while the (R=RCH)CO group r
Publicado em: 1994
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12. Laboratory decontamination and destruction of carcinogens in laboratory wastes–some hydrazines