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1.
Helio Gauze Bonacorso Arci Dirceu Wastowski Nilo Zanatta Marcos Antonio Pinto Martins 《合成通讯》2013,43(8):1457-1465
A convenient method for the synthesis of alkyl[aryl]-substituted 5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-methylpyrazole (2) from a new ring transformation reaction of alkyl[aryl]-substituted-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-pyrazolethiocarboxyamide (1) with methylhydrazine in THF, and the thermal dehydration of 2, are reported. 相似文献
2.
Helio G. Bonacorso Marli R. Oliveira Michelle B. Costa Letícia B. Da Silva Arci D. Wastowski Nilo Zanatta Marcos A. P. Martins 《Journal of heterocyclic chemistry》2005,42(4):631-637
A convenient and general method for the regiospecific synthesis of three novel series of 1‐(2‐thenoyl)‐, 1‐(2‐furoyl)‐ and 1‐(isonicotinoyl)‐3‐alkyl(aryl)‐5‐hydroxy‐5‐trifluoromethyl‐4,5‐dihydro‐1H‐pyrazoles, in good yields (53 – 91 %), from the cyclocondensation reactions of 1,1,1‐trifluoro‐4‐alkoxy‐4‐alkyl(aryl)‐but‐3‐en‐2‐ones, where alkyl = H and Me; aryl = ‐C6H5, 4‐CH3C6H4, 4‐CH3OC6H4, 4‐FC6H4, 4‐ClC6H4, 4‐BrC6H4, 4‐NO2CgH4 with 2‐thiophenecarboxylic hydrazide, furoic hydrazide and isonicotinic acid hydrazide, respectively, is reported. Subsequently dehydration reaction of phenyl substituted 2‐pyrazolines with P2O5 furnished the corresponding 1H‐pyrazoles as mixture of regioisomers and in low yields (35 – 36 %). 相似文献
3.
Helio G. Bonacorso Fernando J. Righi Isadora R. Rodrigues Cleber A. Cechinel Michelle B. Costa Arci D. Wastowski Marcos A. P. Martins Nilo Zanatta 《Journal of heterocyclic chemistry》2006,43(1):229-233
A new, efficient and easy route for the preparation of a series of 2‐alkyl(aryl) substituted 4‐oxo‐4H‐pyrido‐[1,2‐a]pyrimidines, where alkyl = CH3; aryl = C6H5, 4‐FC6H4, 4‐ClC6H4, 4‐BrC6H4, 4‐CH3C6H4, 4‐OCH3C6H4, 4‐NO2C6H4 in 45–80 % yield from the reaction of β‐alkoxyvinyl trichloromethyl ketones with 2‐aminopyridine under mild conditions, is then reported. 相似文献
4.
Dirceu Bagio 《代数通讯》2013,41(10):3658-3678
In this article, we introduce the notion of a partial action of a groupoid on a ring as well as we give a criteria for the existence of a globalization of it. We construct a Morita context associated to a globalizable partial groupoid action, and we introduce the notion of a partial Galois extension, which is related to the strictness of this context. 相似文献
5.
Helio Gauze Bonacorso Sandra R. T. Bittencourt Arci D. Wastowski Alexandre P. Wentz Nilo Zanatta Marcos A. P. Martins 《Journal of heterocyclic chemistry》1999,36(1):45-48
The synthesis and isolation of the intermediates N-[1-aryl(alkyl)-3-oxo-4,4,4-trichloro-1-buten-1-yl]-o-phenylenediamines 2a-f and the corresponding 2-trichloromethyl-4-aryl-3H-1,5-benzodiazepines 3c-g or benzimidazoles 4a-b derivatives obtained from the intramolecular cyclization of 2a-f or from direct cyclo-condensation reaction of β-alkoxyvinyl trichloromethyl ketones 1a-g with o-phenylenediamine, is reported. Depending of the structure of the β-alkoxyvinyl trichloromethyl ketones or the N-[1-aryl(alkyl)-3-oxo-4,4,4-trichloro-buten-1-yl]-o-phenylenediamines and the reactions conditions, benzimidazoles or 3H-1,5-benzodiazepines were obtained. 相似文献
6.
Helio G Bonacorso Hilario Lewandowski Roberta L Drekener Michelle B Costa Claudio M.P Pereira Arci D Wastowski Clóvis Peppe Marcos A.P Martins Nilo Zanatta 《Journal of fluorine chemistry》2003,122(2):159-163
A new series of six 3-aryl-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-picolinoylpyrazole hydrochlorides were synthesised in one-step in high yields by the reaction of β-methoxyvinyl trifluoromethyl ketones with 2-pyridinecarboxamidrazone in the presence of hydrochloric acid. The hydrochloride salts were easily converted to the respective new series of free trifluoromethylated 4,5-dihydro-1H-1-picolinoylpyrazoles using triethylamine in anhydrous diethyl ether. X-ray structure and NMR data from the pyrazole hydrochlorides are reported. 相似文献
7.
H.G Bonacorso I.S Lopes A.D Wastowski N Zanatta M.A.P Martins 《Journal of fluorine chemistry》2003,120(1):29-32
The synthesis of a novel series of eleven 6-aryl(5-methyl)-4-trifluoromethyl-2(1H)-pyrimidinones, where aryl=Ph, 4-CH3Ph, 4-FPh, 4-ClPh, 4-BrPh, 4-OCH3Ph and alkyl=H, CH3, from the reaction of 4-aryl-4-methoxy-1,1,1-trifluoro-3-buten-2-ones with urea in the presence of hydrochloric acid, is reported. Trifluoroacetylation of acetophenone- and propiophenone-dimethylacetals derived from phenones, was employed to obtain the precursors. 相似文献
8.
In this article we prove that if S is a faithfully projective R-algebra and H is a finite inverse semigroup acting on S as R-linear maps such that the fixed subring S H = R, then any partial isomorphism between ideals of S which are generated by central idempotents can be obtained as restriction of an R-automorphism of S and there exists a finite subgroup of automorphisms G of S with S G = R. 相似文献
9.
Helio G. Bonacorso Mauro N. Muniz Arci D. Wastowski Nilo Zanatta Marcos A. P. Martins 《Heteroatom Chemistry》2003,14(2):132-137
A convenient method for the synthesis of a novel series of 11, specifically substituted, noncondensed 5,5‐bicycles 2‐[3‐phenyl‐5‐hydroxy‐5‐trichloromethyl‐4,5‐dihydro‐1H‐pyrazol‐1‐yl]‐4‐aryl‐5‐alkylthiazoles ( 3a–k ; 65–94% yield) from the reactions of 3‐phenyl‐5‐hydroxy‐5‐trichloromethyl‐4,5‐dihydro‐1H‐1‐pyrazolethiocarboxyamide ( 1 ) with substituted 2‐bromo‐4′‐acetophenones ( 2a–f ) and 2‐bromo‐4′‐propiophenones ( 2g–k ) is reported. Dehydration of compounds 3a–k with a mixture of concentrated sulfuric acid/chloroform furnished the corresponding 2‐[3‐phenyl‐5‐trichloromethyl‐1H‐pyrazol‐1‐yl]‐4‐aryl‐5‐alkylthiazoles ( 4a–k ) in good yields (61–93%). © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:132–137, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10113 相似文献
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