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Cyclization of 3-cyclopent-2-enyl-4-hydroxy[1]benzopyran-2-one (1) with cold cone. sulfuric acid gave a mixture of two products, 2 (10%) and 3 (80%). However, on treatment with mercuric chloride 1 furnished the linear product 4 in 60% yield while with mercuric acetate the bicyclic product 8 was obtained in 50% yield. The structures of products are established by chemical correlation. 相似文献
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The irradiation of the title compounds 6 and 12 in isooctane and benzene was investigated. The photochemical reactions took place sluggishly upon n→π* excitation (λ > 300 nm) in deoxygenated solutions but more rapidly in the presence of air; deconjugation to yield β,γ-unsaturated ketones and lumiketone rearrangement were the main primary photochemical reactions. In contrast, intramolecular hydrogen abstraction by the Cα-carbon was the main reaction upon π→* excitation (λ = 254 nm). 相似文献
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P. Venkateshwarlu M. V. S. R. K. Chaitanya P. K. Dubey 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):711-721
Abstract of 1,4-dihydro-4-oxo-1,8-naphthyridine-3-carbohydrazide (4) with substituted phenyl isothiocyanates (5) in ethanol under reflux for 30 min gave thiosemicarbazide derivatives 6, which on cyclization in 2N NaOH under refluxing conditions for 1 h resulted in 3-(5-mercapto- 4-phenyl-4H-1,2,4-triazol-3-yl)-1,8-naphthyridin-4(1H)-one (7). Alternatively, 7 could also be prepared from following sequence of reactions, i.e., 4 → 8 → 7. In another sequence of reactions, condensation of 7 with chloroacetic acid in dimethylformamide (DMF) and K2CO3 as a mild base at 120 °C for 2 h resulted in 2-((5-(1,4-dihydro-4-oxo-1,8-naphthyridin-3-yl)-4-phenyl-4H-1,2,4-triazol-3-yl)sulfanyl)acetic acid (10). The latter, on reaction with substituted o-phenylenediamine (11) in 6N HCl for 4 h yielded 3-(5-((1H-benzo[d]imidazol-2-yl)methylthio)-4-phenyl-4H-1,2,4-triazol-3-yl)-1,8-naphthyridin-4(1H)-one (12). Alternatively, 12 could also be prepared by reacting 7 with 13 in DMF and K2CO3 as a mild base at 120 °C for 2 h, followed by oxidation with H2O2 resulting in the corresponding sulfonyl derivatives 14. 相似文献
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Michael P. Zawistoski 《Journal of heterocyclic chemistry》1990,27(3):519-521
The title compound 3b was synthesized in three steps from acetaminothioacetamide ( 4b ) in 15% overall yield. This represents the first synthesis of a 2-guanidinomethylthiazole, which is a homolog of an important pharmacophore, 2-guanidinothiazole. 相似文献
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L. A. Shemchuk V. P. Chernykh O. S. Krys’kiv 《Russian Journal of Organic Chemistry》2006,42(5):752-756
A preparation method was developed for [1,2,4]triazino[6,1-b]quinazoline-4,10-diones using isatoic anhydride, carboxylic acids hydrazides, ethyl oxalyl chloride, and hydroxylamine. 相似文献
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Vladimir Mironov Gulnara Ivkova Liliya Abdrakhmanova Liliya Burnaeva Kristina Kuzmina 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):162-163
Abstract 2-(5-Methyl-2-phenyl-2Н-1,2,3-diazaphosphol-4-yl)-4H-benzo[d]-1,3,2-dioxaphosphorin-4-one 1 readily reacts with hexafluoroacetone, mesoxalic acid diethyl ester, trifluoropyruvic acid ethyl ester and chloral to give 2-(5-methyl-2-phenyl-2H-1,2,3-dizaphosphole-4-yl)-derivatives of 1,3,2- and 1,4,2-dioxaphosphepines. 相似文献
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The title compound 1 has been synthesised through the intermediacy of the salt 5 obtained by acid hydrolysis of the obtically active β-carboline derivative 10,11-cyclohexylidene-12β-hydroxy-13β-(l-tetrahydro-β-carbolinyl)tetrahydrofuran (4). 相似文献
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The action of 2-mercaptoacetic acid, thiosemicarbazide and hydrazine hydrate on the titled compound 1 is studied. On the other hand, the behaviour of the titled compound towards thiourea, ethyl acetoacetate and malononitrile under Michael's conditions is reported. The structure of the new heterocycles 2 - 8 is discussed in the light of IR and 1HNMR spectra. 相似文献
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DongMeiCAI MinJieLI DaLiangLI TianPaYOU 《中国化学快报》2004,15(2):163-166
Novel C-nucleosides of tiazofurin analogue (2-[2-(hydroxymethyl)-1,3-dioxolan-5-yl] 1,3-thiazole-4-carboxamide) and its thiol-substituted derivative (2-[2-(mercaptomethyl)-1,3-dioxolan-5-yl] 1, 3-thiazole-4-carboxamide) were synthesized from methyl acrylate through a multistep procedure. Their structures were confirmed by IR, ^1HNMR, ^13CNMR and elemental analysis. 相似文献
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Thermal [3,3] sigmatropic rearrangement of 6-cyclohex-2-enyloxy-1-methylquinolin-2(1H)-one (3) afforded 5-cyclohex-2-enyl-6-hydroxy-l-methyl-quinolin-2(1H)-one (4) in 86% yield. Compound 4 on treatment with pyridine hydrotribromide in CH2Cl2 gave exclusively non-bridged product 6 (85%) whereas compound 4 by a different route viz., acetylation followed by bromine addition and cyclization gave the bicyclic product 7 (80%). Compound 4 also furnished a bicyclic product 11 (80%) on treatment with cone. H2SO4. 相似文献
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B. Srinivasa Reddy A. Naidu P. K. Dubey 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):598-605
Abstract Condensation of 2-mercapto-3H-quinazolin-4-one (1) with chloroacetic acid gave 4-oxo-3,4-dihydroquinazoline-2-yl-sulfanyl)-acetic acid (2) that with anthranilamide (3) gave 2-(4-oxo-3,4-dihydroquinazolin-2-ylsulfanylmethyl)-3H-quinazolin-4-one (4). Oxidation of 4 with sodium hypochlorite in alkaline medium gave the novel product, 2-(4-oxo-3,4- dihydroquinazolin-2-ylsulfinyl methyl)-3H -quinazolin-4-one) (5). The entire sequences of reactions in this work have been carried out using eco-friendly solvents and green conditions. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
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