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41.
L. G. Klapshina V. V. Semenov A. N. Kornev V. S. Rusakov O. I. Shchegolikhina A. A. Zhdanov G. A. Domrachev 《Russian Chemical Bulletin》1998,47(3):478-481
The photochemical interaction of polyphenylferrisiloxane with some oligoorganosilanes in benzene solutions has been studied by UV, IR, ESR, and Mössbauer spectroscopy. Silylene species formed during photolysis of oligoorganosilanes react with the high-spin iron(III) to reduce the latter to low-spin iron(II). The formation of the low-spin state of iron(II) was supported by measurements of the magnetic moments. The insertion of the silylene species into the polymer chain to form the Fe?Si bond occurs due to the photoreaction. 相似文献
42.
V. P. Kislyi E. B. Danilova V. V. Semenov A. A. Yakovenko F. M. Dolgushin 《Russian Chemical Bulletin》2006,55(10):1840-1847
Base-catalyzed cyclization of O-alkylated α-hydroxyimino nitriles gave mixtures of 4-aminoisoxazoles and 5-aminooxazoles, their ratio depending on the substituent
structures and the reaction conditions. The formation mechanism of 5-aminooxazoles in this reaction is discussed.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1773–1780, October, 2006. 相似文献
43.
A. A. Bogolyubov N. B. Chernysheva V. V. Nesterov M. Yu. Antipin V. V. Semenov 《Chemistry of Heterocyclic Compounds》2004,40(8):992-1001
The composition and yields of the products from the reaction of 4,4-dialkyl-5-methylene-1,3-dioxolan-2-ones with amidines depend on the structure of the initial amidine and on the reaction conditions. 2-Aminopyridines lead to 3-substituted 4-hydroxy-4-methyloxazolidin-2-ones and 4-methylene-oxazolidin-2-ones and also to sym-carbamides. 2-Amino-4,6-dimethylpyrimidine leads to the corresponding 4-methyleneoxazolidin-2-one. 3-Aminothiazoles give linear oxourethanes and sym-carbamides. 相似文献
44.
7-Iodo- and 7,8-diiodo-4-(3-dimethylaminopropylamino)quinolines and 7-iodo-4-(3) dipropyl-aminopropylamlno)- and 7-iodo-4-(3-diallylaminopropylamino)quinoline were obtained by the reaction of 7-iodo- and 7,8-diodo-4-chloroquinolines with the corresponding diamines. The catalytic hydrogenation of 7-iodo-4-(3-diallylaminopropylamino)quinoline at normal pressure leads to 7-iodo-4-(3-dipropylaminopropylamino)quinoline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 972–975, July, 1980. 相似文献
45.
N. Batbaryar D. Batsurén A. A. Semenov M. N. Sultankhodzhaev 《Chemistry of Natural Compounds》1993,29(5):658-661
In the course of a further study of the alkaloids of the epigeal part of Aconitum turczaninowiia new alkaloid has been isolated, which has been named turpelline. A structure for turpelline has been proposed on the basis of a study of its IR, mass, PMR, 13 C NMR, and 2D COSY spectra. 相似文献
46.
Reactions of organo(trichloromcthyl)silanes RMc2SiCCl3 (R = Me, Ph, Mc3Si) with aluminum chloride have been studied. The interaction of trimetltyl(tricltlorometltyl)silane with AlCl3 carried out in cyclohexane or in benzene leads to Me3SiCHCI2 (in 75 % yield) or ClMe2SiCPh2Me (in 70 % yield), respectively; whereas no conversions are observed inn-hexane and methylene chloride. Treatment of dimetltyl(phenyl)(ricltloromethyl)silane with aluminum chloride in an-C5H12/CH2CI2 mixture gives an aromatic cross-linked insoluble polymer. The reaction of pentamethyl(trichloromcthyl)disilane (R = Mc3Si) with AICl3 in pentane affords the rearrangement product, Me3SiCCl2SiMc2Cl, in 65 % yield. In methylene chloride the further cleavage of the disilane occurs to yield Me2SiCl2 and CH2=CHMe2SiCl.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1511-1515, June, 1996. 相似文献
47.
Yarovenko V. N. Semenov S. L. Zavarzin I. V. Ignatenko A. V. Krayushkin M. M. 《Russian Chemical Bulletin》2003,52(2):451-456
The influence of catalysts, acid chlorides, and solvents on the acylation of methyl 2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate was studied. The use of AlCl3 allows the regioselective introduction of the acyl group into position 3 to be performed, whereas the acyl group is regioselectively introduced into position 6 of thienopyrrole when SnCl4 is used. 相似文献
48.
Buneva VN Kanyshkova TG Vlassov AV Semenov DV Khlimankov DYu Breusova LR Nevinsky GA 《Applied biochemistry and biotechnology》1998,75(1):63-76
Various catalytically active antibodies (Abs), or abzymes, have been detected recently in the sera of patients with autoimmune
pathologies, in whom their presence is probably associated with autoimmunization. Normal humans are generally not considered
to have abzymes, since no obvious immunizing factors are present. Here is shown by different methods that IgG from the milk
of normal females possesses both DNase and RNase activities. The activities were also present in the IgG F(ab′)2 and Fab fragments.
Affinity modification of IgG by the chemically reactive derivative of an oligonucleotide led to preferential modification
of the L chain of IgG. After separation of the subunits by sodium dodecyl sulfate electrophoresis in a gel containing DNA,
an in-gel assay showed DNase activity in the L chain. The L chain separated by affinity chromatography on DNA-cellulose was
catalytically active. These findings speak in favor of the generation of cat alytic Abs by the immune system of healthy mothers.
It is known that the treatment of adults with DNases and RNases offers protection from viral and bacterial diseases. Since
breast milk protects the infants from infec tions until the immune system is developed, this raises the possibility that catalytic
Abs like nucleases, may possess a protective role. 相似文献
49.
A. T. Baryshnikov V. I. Erashko N. I. Zubanova B. I. Ugrak S. A. Shevelev A. A. Fainzilberg V. V. Semenov 《Russian Chemical Bulletin》1992,41(9):1657-1664
The condensation of dinitromethane with glyoxal has been investigated and it has been demonstrated that 1,1,4,4-tetranitro-2,3-butandiol, -hydroxy-,-dinitropropionic acid or their mixture may be formed. Interaction of 1,1,4,4-tetranitro-2,3-butandiol or 1,4-dibromo-1,1,4,4-tetranitro-2,3-butanediol diacetates with sodium azide leads to bis(5-nitro-1,2,3-triazol-4-yl) via intermediate 1,1,4,4-tetranitro-1,3-butadiene.For communication 3, see [1].N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2123–2131, September, 1992. 相似文献
50.
G M Rodchenkov A N Vedenin V P Uralets V A Semenov 《Journal of chromatography. A》1991,565(1-2):45-51
Human urinary metabolites of the synthetic corticosteroids prednisone and prednisolone were detected in the course of gas chromatographic steroid profiling as methoxime-trimethylsilyl derivatives. Metabolites were provisionaly identified by combined gas chromatography-mass spectrometry. The major metabolites were 11-keto/11-hydroxy conversion products, 20-hydroxy and 4,5-dihydro analogues of the parent drugs. Cortisone, 6-hydroxy and fully saturated A-ring compounds were minor metabolites. Retention indices and mass spectral data are presented. 相似文献