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41.
G. P. Smirnova 《Russian Chemical Bulletin》1990,49(1):159-164
Gangliosides were isolated from the starfishEvasterias echinosoma and their structures were elucidated by chemical and physicochemical methods. Two major gangliosides were found to be disialogangliosides,
whose carbohydrate chain is based on the trisaccharide β-N-acylgalactosaminyl-(l→3)-β-galactosyl-(l→4)-β-glucose (acyl is formyl or acetyl), both residue at of 8-O-methyl-N-acetylneuraminic acid being attached to theN-acylgalactosamine residue at positions 3 and 6. The minor components are disialogangliosides with linear carbohydrate chains
in which the terminal sialic acid residue is attached to the penultimateN-acetylneuraminic acid residue at positions 4, 8, or 9. The lipid part of the gangliosides consists of sphingenine and unsubstituted
fatty acids (mainly, palmitic and stearic acids).
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 156–161, January, 2000. 相似文献
42.
V. N. Ananin P. A. Vityaz N. P. Glukhova V. E. Romanenkov T. A. Smirnova A. I. Trokhimetz 《Reaction Kinetics and Catalysis Letters》1985,27(2):393-397
The structure of oxide films of aluminium powders has been established to depend on the size of its particles. The temperature dependence of the oxidation of the powder in air is ascribed to changes in both the structure of the oxide laver and the pressure of saturated aluminium vapor. The porous, permeable product consists of hollow microspheres of -Al2O3.
. , . , –Al2O3.相似文献
43.
T. V. Golovko O. B. Smirnova N. P. Solov’eva O. S. Anisimova V. G. Granik 《Russian Chemical Bulletin》2007,56(5):1032-1040
Condensation of lactim ethers of 3,4-dihydrocarbostyril and 1H-2,3,4,5-tetrahydrobenz[b]azepin-2-one with malonodinitrile, cyanoacetamide, and ethyl cyanoacetate gave the corresponding 2-methylidene derivatives.
Their reactions with dimethylformamide diethyl acetal followed by cyclization into benzo[b][1,6]naphthyridines and pyrido[4,3-b]benz[f ]azepines were studied.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 995–1002, May, 2007. 相似文献
44.
V. N. Marshalkin T. V. Smirnova A. L. Chimishkyan S. I. Orlov 《Chemistry of Heterocyclic Compounds》1985,21(5):510-513
2-Phenylindan-1,3-dione reacts with aryl isocyanates in benzene in the presence of catalytic amounts of triethylamine with the formation of 3-aryl -3a-phenylindano-[2,1-d]oxazolidine-2,4-diones. In pyridine, this reaction leads to 2-arylcarbamoyl-2-phenylindan-1,3-dione.Translated from Khimiya Geterotsklicheskikh Soedinenii, No. 5, pp. 612–615, May, 1985. 相似文献
45.
B. V. Lebedev L. Ya Tsvetkova N. N. Smirnova 《Journal of Thermal Analysis and Calorimetry》1994,41(6):1371-1377
The heat capacitiesC 0 p of polybutene-1, polypentene-1, poly-4-methylpentene-1 and 4-methylphentene-1 were studied calorimetrically from 6 to (500–700) K. Temperatures, enthalpies of melting of various crystalline forms and the parameters of the glass transition were determined. The thermodynamic functionsH 0(T)?H0(0), S0(T) andG 0(T)?H0 (0) were calculated between 0 K and (500–700) K. From the calorimetric values obtained and literature data, the thermodynamic characteristics of the following processes were estimated for the corresponding alkenes-1, andcis-andtrans-alkenes-2: the polymerization of alkenes-1, the monomer-isomerization polymerization ofcis- andtrans-alkenes-2 to polyaklenes-1 and the isomerization ofcis- andtrans-aklenes-2 to alkenes-1 in the same temperature interval at standard pressure. 相似文献
46.
A. I. Pavlyuchenko V. V. Titov N. I. Smirnova V. T. Grachev 《Chemistry of Heterocyclic Compounds》1980,16(7):681-684
Liquid-crystal 2-cyano-5-[p-alkyl(alkoxy)phenyl]pyridines were synthesized by the reaction of 1-dimethylamino-3-dimethylimmonia-2-[p-alkyl (alkoxy)phenyl]propene perchlorates with 2-acetylfuran and subsequently through 2-furyl-5-[p-alkyl(alkoxy)phenyl]pyrylium perchlorates and 2- (2-furyl)-5-[p-alkyl (alkoxy)phenyl]pyridines by conversion of the latter to 5-alkyl(alkoxy)phenylpyridine-2-carboxylic acids, from which the cyano derivatives were obtained by the usual scheme through the amides. The intermediate arylfurylpyridines and arylpyridine-2-carboxylic acid imides also display liquid-crystal properties.Translated from Khimiya Geterotskilicheskikh Soedinenii, No. 7, pp. 888–891, July, 1980. 相似文献
47.
Starukh G. N. Smirnova N. P. Eremenko A. M. Chuiko A. A. Abdel-Shafi A. A. Worrall D. R. Wilkinson F. 《Theoretical and Experimental Chemistry》2001,37(2):103-107
We have used fluorescent spectroscopy and laser flash photolysis to investigate the photonics of pyrene molecules in a pyrene–-cyclodextrin inclusion complex in various media. We have observed a protective effect of -cyclodextrin relative to solubilized pyrene molecules during quenching of fluorescence by Ti ions (or titanium dioxide particles) in mixed colloids. In the presence of a precursor of silica (a TEOS solution), the pyrene molecules react with the colloidal silica particles formed, and the reaction is accompanied by decomposition of the pyrene–-cyclodextrin inclusion complex and efficient photoionization of pyrene. 相似文献
48.
A. A. Ponomarev A. S. Chegolya N. S. Smirnova V. N. Dyukareva 《Chemistry of Heterocyclic Compounds》1967,2(2):113-117
This paper gives the results obtained by liquid phase catalytic hydrogenation under pressure, over ruthenium catalysts, of furan aldehydes, ketones, and carboxylic acids. It is shown that the ruthenium catalysts are highly effective for hydrogenating the furan ring, ethylenic double bonds, and the carbonyl group, though they are not selective with respect to them. At room temperature the furan ring is mostly reduced to a tetrahydrofuran one. It is confirmed that compounds containing the 1, 6-dioxaspiro [4, 4]-nonane grouping are formed by hydrogenating furfurylidene aldehydes and ketones, and -furylalkanols.For Part XXX see [15]. 相似文献
49.
The thermodynamic properties of styrenetricarbonylchromium, -methylstyrenetricarbonylchromium, and p-methylstyrenetricarbonylchromium were studied with adiabatic vacuum and dynamic calorimeters. The heat capacity in the range 5-450 K (error about 0.3% in most cases) and the temperatures and enthalpies of the phase transitions were determined. The experimental data were used to calculate the thermodynamic functions C
0
p(T), H
0(T) - H
0(0), S
0(T), and G
0(T) - H
0(0) for the range from 0 to 330-400 K, and also the isochoric heat capacity C
v and its lattice (Cv,latt) and atomic (C
v,at) contributions for the range from 0 K to T
0
m; the parameters = C
0
p/C
v were evaluated. The thermodynamic properties were considered in relation to the composition and structure of the compounds. 相似文献
50.