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101.
V. E. Kataev A. P. Timosheva A. I. Nugmanov A. T. Gubaidullin I. Yu. Strobykina R. R. Shagidullin L. V. Avvakumova O. I. Militsina 《Russian Journal of General Chemistry》2007,77(6):1069-1077
Dielcometry, method of dipole moments, IR spectroscopy, and computer simulation were used to show that dicarboxylic acid esters derived from 16-hydroxyisosteviol (ent-16-hydroxybeyeran-19-oic acid) exist in CCl4 solutions as tweezer-like or open-chain structures, or dimers with various steric structures, depending on the degree of dilution. Concentrations at which both the esters and parent dicarboxylic acids undergo structural rearrangement were established. The structure of three esters was confirmed by X-ray diffraction. 相似文献
102.
Evgeny A. Kataev Patricia Pantos Elizabeth Karnas Grigory V. Kolesnikov Ivan G. Tananaev Vincent M. Lynch 《Supramolecular chemistry》2015,27(5-6):346-356
Cyclo[8]pyrrole, an octapyrrolic expanded porphyrin with no meso-linking atoms, was found to interact with a series of anions in the solid state and in a chloroform solution. The anion selectivities have been determined relative to a structurally characterised salt, H2cyclo[8]pyrrole2+·I? ·I3 ? , via counter anion exchange. Although cyclo[8]pyrrole demonstrates a general selectivity for sulfate, it interacts well with both the pertechnetate and perrhenate anions. Moreover, it has been shown to act as a phase-transfer catalyst facilitating the extraction of pertechnetate from an aqueous to an organic phase in the presence of sulfate. 相似文献
103.
Yakhvarov D Trofimova E Sinyashin O Kataeva O Budnikova Y Lönnecke P Hey-Hawkins E Petr A Krupskaya Y Kataev V Klingeler R Büchner B 《Inorganic chemistry》2011,50(10):4553-4558
The reaction of [NiBr(2)(bpy)(2)] (bpy = 2,2'-bipyridine) with organic phosphinic acids ArP(O)(OH)H [Ar = Ph, 2,4,6-trimethylphenyl (Mes), 9-anthryl (Ant)] leads to the formation of binuclear nickel(II) complexes with bridging ArP(H)O(2)(-) ligands. Crystal structures of the binuclear complexes [Ni(2)(μ-O(2)P(H)Ar)(2)(bpy)(4)]Br(2) (Ar = Ph, Mes, Ant) have been determined. In each structure, the metal ions have distorted octahedral coordination and are doubly bridged by two arylphosphinato ligands. Magnetic susceptibility measurements have shown that these complexes display strong antiferromagnetic coupling between the two nickel atoms at low temperatures, apparently similar to binuclear nickel(II) complexes with bridging carboxylato ligands. Cyclic voltammetry and in situ EPR spectroelectrochemistry show that these complexes can be electrochemically reduced and oxidized with the formation of Ni(I),Ni(0)/Ni(III) derivatives. 相似文献
104.
M. G. Korochkina V. M. Babaev I. Yu. Strobykina A. D. Voloshina N. V. Kulik V. E. Kataev 《Chemistry of Natural Compounds》2012,47(6):914-917
Previously unreported bis-quaternized ammonium derivatives of the diterpenoid isosteviol (16-oxo-entbeyeran-19-oic acid) were
synthesized. The compound in which the two quaternized N atoms were joined by a dodecamethylene spacer had the greatest antimicrobial
activity and was comparable in activity with ciprofloxacin and clotrimazole. 相似文献
105.
Obituary
Antonina Nikolaevna Grafova 相似文献106.
Strobykina I. Yu. Nemtarev A. V. Garifullin B. F. Voloshina A. D. Sapunova A. S. Kataev V. E. 《Russian Journal of Organic Chemistry》2019,55(1):17-24
Russian Journal of Organic Chemistry - Isosteviol reacted with α,ω-dibromoalkanes to give 19-(ω-bromoahkyl) esters which were treated with tetraethyl methylenebis(phosphonate) to... 相似文献
107.
Sharipova R. R. Belenok M. G. Strobykina I. Yu. Kataev V. E. 《Russian Journal of Organic Chemistry》2019,55(4):508-513
Russian Journal of Organic Chemistry - First phosphorylated glycoconjugates were synthesized in three stages on the basis of isosteviol, d-arabinofuranose, and d-ribofuranose. In the first stage,... 相似文献
108.
Olga V. Andreeva Maya G. Belenok Liliya F. Saifina Marina M. Shulaeva Alexey B. Dobrynin Radmila R. Sharipova Alexandra D. Voloshina Alina F. Saifina Aidar T. Gubaidullin Bulat I. Khairutdinov Yuriy F. Zuev Vyacheslav E. Semenov Vladimir E. Kataev 《Tetrahedron letters》2019,60(47):151276
A series of novel 1,2,3-triazolyl nucleoside analogues was synthesized via the CuAAC reaction of N1-alkynyl uracil, 6-methyluracil, 3,6-dimethyl uracil, thymine and quinazolin-2,4-dione with protected azido β-d-ribofuranose. The obtained compounds differ in both the nature of the pyrimidine-2,4-dione fragment and the length of the polymethylene linker connecting it with the β-d-ribofuranosyl-1,2,3-triazol-4-yl moiety. The 1,2,3-triazolyl nucleoside analogues were evaluated for their cytotoxicity in vitro. 相似文献
109.
A. A. Kamashev P. V. Leksin J. Schumann J. Thomas T. Gemming V. Kataev B. Büchner I. A. Garifullin 《JETP Letters》2017,106(12):805-809
The superconductor/ferromagnet proximity effect in the Pb/Co2Cr1–xFe x Al bilayer systems has been studied. Thin films of the Heusler alloy Co2Cr1–xFe x Al have been prepared at different substrate temperatures. It has been established using Andreev spectroscopy of point contacts that the degree of spin polarization of conduction electrons in the Heusler alloy is on the order of 30 and 70% for the films prepared at a substrate temperature of 300 and 600 K, respectively. It has been found that the dependence of the superconducting transition temperature on the thickness of the Pb layer at a fixed thickness of the Heusler layer is determined by the degree of spin polarization of the conduction band in the ferromagnetic layer. 相似文献
110.
L. G. Lavrentyeva Yu. G. Kataev V. A. Moskovkin M. P. Yakubenya 《Crystal Research and Technology》1971,6(5):607-622
The effect of the substrate orientation and the supersaturation on the growth rate and doping level of vapor grown GaAs is considered. Experimental results are discussed in terms of crystal growth theory developed by BURTON , CABRERA , FRANK and CHERNOV (BCFCh). It is shown that the main predictions of theory are in agreement with the experimental results. At the same time experimental results, on the whole, are more complicated than predicted by simple crystal growth model. It can be concluded that the BCFCh-theory is applicable for analysing the growth rate and doping level anisotropy for vapor grown crystals. 相似文献