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1.
An approach to the synthesis of substituted ethyl 3-(3-hydroxy-2-thienyl)-3-oxopropanoates was developed based on the reaction of ethyl cyanoacetate, carbon disulfide, and ethyl 4-chloroacetoacetate. The reaction regioselectively involved the ester group, rather than the nitrile one like in the case when malononitrile or cyanacetamide were used.  相似文献   

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The luminescence spectral properties of 3-pyridyl-7-hydroxy-2-iminocoumarin and 3-(2-methylthiazole)-7-hydroxy-2-iminocoumarin were studied in ethanol solutions at different values of pH and also in other solvents differing in polarity. In their ethanol solutions, the compounds can exist as neutral molecules, anions, cations, and zwitterions. The spectral properties and geometry were studied for all possible forms of these compounds by the INDO/S quantum-chemical method.  相似文献   

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It was established by IR, UV, and PMR spectroscopy that N-unsubstituted and N-(n-alkyl, sec-alkyl, or aryl)-2-(2-imidazolylcarbonyl)benzamides obtained from imidazo[1,2-b]isoquinoline-5,10-dione and ammonia or amines have the 3-hydroxy-3-(2-imidazolyl)isoindolinone chain structure in the crystalline state and in solutions in dimethyl sulfoxide. The N-(tert-alkyl)amides exist in the open form under these conditions. Protonation of the imidazole nitrogen atom in the N-(tert-butyl)amide molecule leads to its cyclization to 3-hydroxyisoindolinone. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 335–339, March, 1980.  相似文献   

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Previously unknown cis-1-(1-adamantyl)-2,3-epoxy-3-R-propanones were highly selectively obtained by epoxidation of ,-unsaturated ketones with hydrogen peroxide in alkaline medium. The regioselectivity of the epoxide ring cleavage with amines (piperidine and morpholine) was studied.  相似文献   

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The reaction of phenyl isocyanate and acetic anhydride with 2-(2-hydroxo-3-chloropropylthio) benzothiazole was studied. At 140 °C, this benzothiazole cyclizes with the formation of quaternary salt which readily reacts with hydrazine and alkali.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1483–1484, November, 1983.  相似文献   

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2,4-Dihydroxy-3-(3,3-dichloroallyl)quinoline, the corresponding 4-mono and 2,4-dichloro derivatives, and substituted -(3-quinolyl)propionic acids were synthesized. -(2-Hydroxy-4-chloro-3-quinolyl) propiolactone was obtained from the latter.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 975–977, July, 1972.  相似文献   

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Three crystalline modifications of the N-chloroacetyl derivative were obtained in the chloroacetylation of 2-(2-aminophenyl)-4-hydroxy-3-phenyl-1-isoquinolone. It was established by IR spectroscopy that they differ with respect to isomeric composition and the character of the intermolecular hydrogen bonds. For the first time, both keto-enol tautomeric forms were isolated in individual form in the 4-hydroxy-1-isoquinolone series.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 542–543, April, 1985.  相似文献   

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The stereoconvergent synthesis of N-Boc-(2R,3S)-3-hydroxy-2-phenylpiperidine from (R)-1-(2-((tert-butyldimethylsilyl)oxy)-1-phenylethyl)piperidin-2-one is described. The key steps involved are α-hydroxylation of quiral lactam with O2, stereoconvergent reduction of (R)- or (S)-3-(benzyloxy)-piperidin-2-one with Red-Al® which afforded in both cases the trans-bicyclic oxazolidine in high stereoselectivity after chromatographic purification and a stereospecific Grignard addition to chiral bicyclic oxazolidine.  相似文献   

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Russian Journal of General Chemistry - Reaction of methyl esters of acylpyruvic acids with a mixture of aromatic aldehyde and 3-picolylamine gave...  相似文献   

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N-Unsubstituted and N-monosubstituted amides of 2-(4-dimethylaminobenzoyl)benzole acid exist in the chain form of 3-hydroxyisoindolinones in the crystalline state and in solutions in dioxane, whereas the tautomeric amide hydroxyisoindolinone equilibrium occurs (except for the methyl derivative) in more polar solvents. The analogous N-(1-adamantanyl)amide exists in the open form and does not undergo cyclization under alkaline catalysis conditions; protonation of the dimethylamino group is accompanied in all cases by splitting out of water to give compounds with a quinoid structure; an equilibrium between the protonated and quinoid forms, which is shifted markedly to favor the latter, is observed for some compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 780–785, June, 1979.  相似文献   

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