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Search Results: 1 - 10 of 130419 matches for " Eugeniya V. Nikitina "
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Methyl 7,8-diacetoxy-11-oxo-5-(2-oxopyrrolidin-1-yl)-7,9-epoxycyclopenta[4,5]pyrido[1,2-a]quinoline-10-carboxylate sesquihydrate
Atash V. Gurbanov,Eugeniya V. Nikitina,Vladimir P. Zaytsev,Fedor I. Zubkov
Acta Crystallographica Section E , 2010, DOI: 10.1107/s160053680905363x
Abstract: The title compound, C26H28N2O9·1.5H2O, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as a sesquihydrate with the O atom of one of the two independent water molecules occupying a special position on a twofold axis. The organic molecule comprises a fused pentacyclic system containing two five-membered rings (cyclopentane and tetrahydrofuran) and three six-membered rings (piperidinone, tetrahydropyridine and benzene). The five-membered rings have the usual envelope conformations, and the central six-membered piperidinone and tetrahydropyridine rings adopt boat and sofa conformations, respectively. In the crystal, there are three independent O—H...O hydrogen bonds, which link the organic molecules and water molecules into complex two-tier layers parallel to (001). The layers are further linked into a three-dimensional framework by attractive intermolecular carbonyl–carbonyl interactions.
Dimethyl 11,13-dimethyl-16-[1,2-bis(methoxycarbonyl)ethenyl]-12-oxo-16,17-dioxa-18-azahexacyclo[,4.16,9.110,14.05,15]octadeca-2,7-diene-2,3-dicarboxylate
Atash V. Gurbanov,Eugeniya V. Nikitina,Elena A. Sorokina,Fedor I. Zubkov
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809050600
Abstract: The title compound, C27H29NO11, is a product of the tandem `domino' Diels–Alder reaction. The molecule comprises a fused hexacyclic system containing four five-membered rings (two dihydrofuran and two tetrahydrofuran) in the usual envelope conformations and two six-membered rings (tetrahydropyridinone and piperidine) adopting slightly flattened boat and chair conformations, respectively. The dispositions of the carboxylate substituents relative to each other are determined by both steric reasons and intermolecular C—H...O hydrogen bonding and attractive antiparallel C=O...C=O interactions [C...O = 2.995 (2) ].
Methyl 4,5-diacetoxy-1-oxo-2-phenylperhydro-4,6-epoxycyclopenta[c]pyridine-7-carboxylate ethanol solvate
Atash V. Gurbanov,Eugeniya V. Nikitina,Inga K. Airiyan,Vladimir P. Zaytsev
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809045528
Abstract: The title compound, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as an ethanol monosolvate, C20H21NO8·C2H6O. The title molecule comprises a fused tricyclic system containing two five-membered rings (cyclopentane and tetrahydrofuran) in the usual envelope conformations and one six-membered ring (piperidinone) adopting a flattened twist–boat conformation.
(4R*,4aR*,7aS*)-5-Oxo-6-phenyl-4a,5,6,7,7a,8-hexahydro-4H-furo[2,3-f]isoindole-4-carboxylic acid
Yuriy I. Horak,Roman Z. Lytvyn,Fedor I. Zubkov,Eugeniya V. Nikitina
Acta Crystallographica Section E , 2013, DOI: 10.1107/s160053681300144x
Abstract: The asymmetric unit of the title compound, C17H15NO4, contains two independent molecules with similar geometric parameters. In both molecules, the conformation of the cyclohexene ring is half-chair, while the pyrrolidinone ring adopts an envelope conformation with the γ-carbon atom of the α-pyrrolidinone ring as the flap. In the crystal, O—H...O hydrogen bonds between the carboxylic and carbonyl groups link alternate independent molecules into chains propagating in the b-axis direction. The crystal packing also features weak C—H...π interactions.
Methyl (9aR*,10S*,11R*,13aS*,13bS*)-9-oxo-6,7,9,9a,10,11-hexahydro-5H,13bH-11,13a-epoxypyrrolo[2′,1′:3,4][1,4]diazepino[2,1-a]isoindole-10-carboxylate
Flavien A. A. Toze,Inga K. Airiyan,Eugeniya V. Nikitina,Elena A. Sorokina
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811040360
Abstract: The title compound, C17H18N2O4, is the methyl ester of the adduct of intramolecular Diels–Alder reaction between maleic anhydride and 1-(2-furyl)-2,3,4,5-tetrahydro-1H-pyrrolo[1,2-a][1,4]diazepine. The molecule comprises a fused pentacyclic system containing four five-membered rings (viz. pyrrole, 2-pyrrolidinone, tetrahydrofuran and dihydrofuran) and one seven-membered ring (1,4-diazepane). The pyrrole ring is approximately planar (r.m.s. deviation = 0.003 ) while the 2-pyrrolidinone, tetrahydrofuran and dihydrofuran five-membered rings have the usual envelope conformations. The central seven-membered diazepane ring adopts a boat conformation. In the crystal, molecules are bound by weak intermolecular C—H...O hydrogen-bonding interactions into zigzag chains propagating in [010]. In the crystal packing, the chains are stacked along the a axis.
Basic lines of legal informatization development in Russian Federation
Robert L. Anakhasyan,Eugeniya V. Tutinas
European Researcher , 2011,
Abstract: The article gives general characteristic of state regulation of legal information retrieval systems use by state authorities and other organizations in the Russian Federation as one of forms of legislation systematization.
A possible model for initiationof ULF oscillation in magma
Y. A. Kopytenko,L.V. Nikitina
Annals of Geophysics , 2004, DOI: 10.4401/ag-3263
Abstract: During the period just prior to an earthquake, an electomagnetic emission develops over seismic zones. In this paper, a model of excitation of magnetic fields over zones of volcanic activity is proposed. Movement of magma along volcanic channels precedes an earthquake, hydrodynamic processes in the moving magma can lead to formation of waves and vortices in the flow which, in turn, can cause development of magnetic fields in conducting magma. During this period, the movement of the magma intensifies leading to a corresponding intensification of the magnetic fields. In this paper, different possible sources of ULF pulsation in magma are examined,and the variable geomagnetic fields induced by this pulsation are estimated.
Value MCP-1 as predict vascular disturbances
Nikitina V.V.,Zaharova N.B.
Saratov Journal of Medical Scientific Research , 2010,
Abstract: Vascular disturbances have been studying for more than 150 years. Nowadays vascular disorders cause many diseases. The article presents the significance of monocytic chemotactic protein-1 (MCP-1) and its function in athero-genesis. The data of the research are considered
Library of Disordered Patterns in 3D Protein Structures
Michail Yu. Lobanov,Eugeniya I. Furletova,Natalya S. Bogatyreva,Michail A. Roytberg,Oxana V. Galzitskaya
PLOS Computational Biology , 2010, DOI: 10.1371/journal.pcbi.1000958
Abstract: Intrinsically disordered regions serve as molecular recognition elements, which play an important role in the control of many cellular processes and signaling pathways. It is useful to be able to predict positions of disordered regions in protein chains. The statistical analysis of disordered residues was done considering 34,464 unique protein chains taken from the PDB database. In this database, 4.95% of residues are disordered (i.e. invisible in X-ray structures). The statistics were obtained separately for the N- and C-termini as well as for the central part of the protein chain. It has been shown that frequencies of occurrence of disordered residues of 20 types at the termini of protein chains differ from the ones in the middle part of the protein chain. Our systematic analysis of disordered regions in PDB revealed 109 disordered patterns of different lengths. Each of them has disordered occurrences in at least five protein chains with identity less than 20%. The vast majority of all occurrences of each disordered pattern are disordered. This allows one to use the library of disordered patterns for predicting the status of a residue of a given protein to be ordered or disordered. We analyzed the occurrence of the selected patterns in three eukaryotic and three bacterial proteomes.
Alen’kina S.A.,Nikitina V.E.
Journal of Stress Physiology & Biochemistry , 2009,
Abstract: It was found that two cell-surface lectins isolated from the nitrogen-fixing soil bacterium Azospirillum brasilense Sp7 and from its mutant defective in lectin activity, A. brasilense Sp7.2.3 can stimulate rapid formation of hydrogen peroxide, associated with an increase in the activities of oxalate oxidase and peroxidase in the roots of wheat seedlings. The most advantageous and most rapidly induced pathway of hydrogen peroxide formation was the oxidation of oxalic acid by oxalate oxidase because in this case, a 10-min treatment of the roots with the lectins at 10 μg ml-1 was sufficient. The data from this study attest that the Azospirillum lectins can act as inducers of adaptation processes in the roots of wheat seedlings.
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