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11.
Russian Journal of General Chemistry - 5-Hydroxy-1,3,6-trimethyluracil has been studied using 1H, 13C, and 15N NMR as well as UV spectroscopy. The constants and thermodynamic characteristics of its...  相似文献   
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Chemistry of Natural Compounds - Claisen–Schmidt reactions of 3-oxoglycyrrhetic acid with aromatic aldehydes in EtOH–NaOH (4N) synthesized 2-arylidene-3-oxo-derivatives in 65–70%...  相似文献   
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Oxidation of 5-hydroxy-6-methyluracil with molecular oxygen in the presence of copper(II) chloride involves formation of a 2 : 1 complex with copper(II). The rates of consumption of initial 5-hydroxy-6-methyluracil and oxygen were determined in the temperature range from 40 to 80°C. A probable reaction mechanism implies fixation and activation of molecular oxygen on the copper(II) complex with 5-hydroxy-6-methyluracil with formation of active oxygen species that are responsible for hydroxylation of the double C5=C6 bond in the uracil molecule.  相似文献   
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It has been discovered experimentally that 5,5,6-trihydroxy-6-methylpyrimidine-2,4-dione is formed on oxidizing 5-hydroxy-6-methyluracil with molecular oxygen in aqueous medium in the presence of copper(II) chloride. Ab initio and DFT calculations on the 6-31G* basis, both in the gas phase and allowing for solvent, showed that the process proceeds with the direct participation of an activated oxygen molecule on the complex CuCl2·(5-hydroxy-6-methyluracil)2. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 586-593, April, 2009.  相似文献   
15.
Russian Journal of Organic Chemistry - Previously unknown 5-alkyl-1,3-bis[(alkylsulfanyl)methyl]-1,3,5-triazinan-2-ones have been syn­thesized by three-component condensation of available...  相似文献   
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Russian Journal of General Chemistry - 5-Hydroxy-6-methyluracil was found to be oxidized by molecular oxygen in an alkaline aqueous solution. The effect of temperature, concentration of alkali and...  相似文献   
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Dissociation constants of 5-methoxy-6-methyluracil, 5-methoxy-1,6-dimethyluracil and 5-methoxy-3,6-dimethyluracil in water are determined. Basing on the obtained рKа1 values, the content of anions in aqueous alkaline solution of 5-methoxy-6-methyluracil was calculated. The results were confirmed by the use of model compounds: 5-methoxy-1,6-dimethyluracil and 5-methoxy-3,6-dimethyluracil using the NMR spectroscopy.  相似文献   
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A new method was examined for the synthesis of multinuclear systems based on dihydroquinoline and quinoline, consisting of the interaction of arylidene--naphthylamines with indandione-1, 3. The reaction of arylidene anilines with indandione-1,3 leads to the formation of arylidenindandiones-1, 3.  相似文献   
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