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1.
The reaction of 2-(2-acetoxyethyl)amino-4-chloro-6-methylpyrimidine with aromatic amines leads to a series of 4-arylamino-2-(2-acetoxyethyl)amino-6-methylpyrimidines. Deacetylation of these compounds proceeds in both acidic and basic media. Most of the arylaminopyrimides obtained exhibit a pronounced antituberculous effect. 相似文献
2.
A. V. Erkin V. I. Krutikov E. B. Smirnova 《Russian Journal of General Chemistry》2008,78(10):1944-1948
2-Substituted 4-arylamino-6-methylpyrimidines were synthesized by stepwise modification of the structure of 6-methyl-2-thiouracyl through the intermediate 2-(ar)alkylthio-6-methyl-4-chloropyrimidines. Some of the compounds synthesized exhibit expressed antimycobacterial activity. 相似文献
3.
The chemomechanical properties and microstructural stability of nanocrystalline PrxCe1 − xO2 − δ solid solutions are studied as a function of temperature by in situ X-ray diffraction measurements under oxidizing conditions at P(O2) ~ 200 mbar. The chemical expansion coefficient of nanocrystalline powder specimens, operative at intermediate temperatures during which Pr4+ is reduced to Pr3+, is found to be similar to that obtained for coarse-grained PrxCe1 − xO2 − δ. This is contrary to reports regarding variation of physical and chemical properties with crystallite size. The thermal expansion coefficient, measured under conditions for which PrxCe1 − xO2 − δ is highly oxygen deficient, was found to be greater than that measured for fully oxidized PrxCe1 − xO2 − δ, with potential sources of these changes discussed. Moreover, the microstructure of nanocrystalline PrxCe1 − xO2 − δ is observed to have excellent stability at working temperatures below 800 °C, enabled by the inherent microstrain in the structure, highlighting the potential application of this material for solid state electrochemical devices. 相似文献
4.
Electrophilic substitution of hydrogen in bicyclic 5-hydroxy-3-methyl-1-(6-methyl-2-methylsulfanylpyrimidin-4-yl)-1H-pyrazole occurs exclusively at the C4 atom of the five-membered heteroring. Unstable electrophilic substitution products are stabilized via addition of the second
substrate molecule with formation of bridged adducts. 相似文献
5.
Metin Ak Gülbanu Koyundereli Çılgı Ferah Diba Kuru Halil Cetişli 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1627-1632
Thermal behavior of 2,4,6-tris(4-(1H-pyrrol-1-yl)phenoxy)-1,3,5-triazine monomer, polypyrrole, and their star shaped copolymer, were investigated using TG and DTA methods. It was found that Tria melts at 517 K and after than it starts to decompose. Decomposition proceeded in two stages which were corresponding to removal of branched groups and remaining core structure degradation, respectively. Polypyrrole and copolymer showed similar thermal behaviors. These compounds decomposed in three stages which are removal of solvent, removal of dopant anion and rest of structure decomposition. The calculation of activation energies of all reactions were realized using model-free (KAS and FWO) methods. The graphs were prepared which show the alteration of activation energy with decomposition ratio. Thermal analysis results showed that dopant anion and solvent removal activation energy values for copolymer are lower than polypyrrole. Star shaped loose-packed novel structure greatly facilitates solvent and dopant anion removal from copolymer. It can be concluded also that thermal analysis can be used as predict package structure of conducting polymers. 相似文献
6.
Polyfluoroalkyl esters of phosphoric, alkylphosphonic and 1-hydroxypolyfluoroalkylphosphonic acids exhibited significant antiesterase
activity against various esterases of animal and microbial origin. Moreover, with some compounds reversible inhibition of
enzymes was observed due to the specific influence of hydrophobic fragments of the target products. 相似文献
7.
A. V. Erkin V. V. Gurzhii I. V. Klaptyuk T. V. Firsanova V. I. Krutikov 《Russian Journal of General Chemistry》2017,87(3):402-406
Fusion 2-(4,6-dimethylpyrimidin-2-yl)-5-methyl-2Н-pyrazol-3-ol with phenols leads to the formation of complexes which exist due to a system of intermolecular N···H–O hydrogen bonds. The complexes are stable at high temperatures: their melting and subsequent thermolysis are accompanied by endothermic effects. 相似文献
8.
The momentum-space coupled-channels-optical (CCO) method is used to study the resonances in electron oxygen collision in the energy region of 9-12 eV, Present results have shown agreement with the available experimental and theoretical results, and new positions of resonances are found by the comparison of total cross sections, 相似文献
9.
Russian Journal of Organic Chemistry - 2-[(2-Amino-6-methylpyrimidin-4-yl)sulfanyl]acetohydrazide reacted with triethyl orthoformate at a molar ratio of 1:1 to give... 相似文献
10.
合成了7,8,17,18-四溴-5,10、15,20-四苯基卟啉钯金属配合物,通过电子光谱,元素分析,IR,^1H NMR测定,确定配合物的组成,同时经放氢功能研究证明该配合物具有光敏性。 相似文献