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71.
72.
Molecular structures of oxime 6-oxo-indolo[2,3-b]-bicyclo[3.3.1]non-2-en 1 and 6-oxo-(5-methoxy-indolo[2,3-b])-bicyclo[3.3.1]non-2-en 2 were determined by X-ray crystal investigation. It was revealed that oxime 1 has anti-configuration in respect to indole-containing framework, and both compounds adopt half-chairchair-conformation. The distortion of rings was evaluated by calculation of the ZP- and CP-puckering parameters. The presence of the methoxy-group in compound 2 was found to lead to the changes in molecular packing in comparison with structure 1.  相似文献   
73.
74.
Reaction of a trinuclear silver pyrazolate {[3,5-(CF3)2Pz]Ag}3 complex with tricyclohexylphosphine at different reagent ratios leads to the formation of heteroleptic dinuclear or tetranuclear complexes. According to the single crystal X-ray analysis of the dinuclear complex, hexane molecules are incorporated into the cavities formed as the result of supramolecular packing. Coordination of a phosphine ligand makes dinuclear silver pyrazolate to exhibit blue emission at room temperature.  相似文献   
75.
Results from investigating interactions in the heparin-Co2+ ion-glycine system are presented. The stoichiometry of cobalt complexes with heparin and glycine compositions CoOHHtpGly4? and CoHepGly3? is established.  相似文献   
76.
77.
Crystallization of N-[(8R)-2-methoxy-5,6,7,8,9,10-hexahydro-6,9-methanocyclohepta[b]indol-8-yl]acetamide was accompanied by oxidation at the C5a–C10a bond with formation of N-[(5S)-10-methoxy-2,8-dioxo-1,2,3,4,5,6,7,8-octahydro-3,6-methano-1-benzazecin-5-yl]acetamide whose structure was determined by X-ray analysis. Docking of this compound into melatonin-binding pocket of MT1A receptor was simulated by computer-assisted molecular modeling.  相似文献   
78.
Reactions of 5-nitrospiro[benzimidazole-2,1′-cyclohexane] 1,3-dioxide with aliphatic amines and sodium hydroxide resulted in removal of one N-oxide oxygen atom and formation of 4-alkylamino- or 4-hydroxy-substituted 5-nitrospiro[benzimidazole-2,1′-cyclohexane] 1-oxides, respectively. The title compound reacted with ammonia and methylamine in the presence of MnO2 with conservation of both N-oxide moieties, and the products were 4-amino- and 4-methylamino-5-nitrospiro[benzimidazole-2,1′-cyclohexane] 1,3-dioxides. The reactions with aromatic amines were accompanied by removal of both N-oxide oxygen atoms with formation of N-aryl-5-nitrospiro[benzimidazole-2,1′-cyclohexane]-4-amines. In the reactions of 5-nitrospiro-[benzimidazole-2,1′-cyclohexane] 1,3-dioxide with sodium azide and aromatic amine hydrochlorides nucleophilic replacement of the 5-nitro group by azido or arylamino occurred, in the first case both N-oxide fragments being conserved. The reactions with aromatic amine hydrochlorides afforded N-aryl-5-nitrospiro[benzimidazole-2,1′-cyclohexan]-4-amine 1-oxides. Treatment of 5-nitrospiro[benzimidazole-2,1′-cyclohexane] 1,3-dioxide with sodium cyanide led to the formation of 5-oxo-3,5-dihydrospiro[benzimidazole-2,1′-cyclohexane]-4-carbonitrile 1-oxide.  相似文献   
79.
Russian Journal of Applied Chemistry - The surface of modifying polymers in filled cellulose nitrate composites was studied by attenuated total internal reflection IR spectroscopy. The qualitative...  相似文献   
80.
A procedure is developed for the gas chromatographic determination of admixtures of permanent gases, CO, CO2, and hydrocarbons in methylsilane with detection limits of 0.02–0.8 ppm. The procedure was applied to the analysis of methylsilane obtained by reducing methyltrichlorosilane with sodium tetrahydrob-orate in an organic solvent. Admixtures of permanent gases and C1–C5 hydrocarbons the in synthesized methylsilane were detected.  相似文献   
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