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151.
Dr. Ramón Fraga Kateryna Len Regis Lutzing Dr. Gilles Laverny Dr. Julian Loureiro Prof. Miguel A. Maestro Prof. Natacha Rochel Prof. Enrique Rodriguez-Borges Prof. Antonio Mouriño 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(53):13384-13389
Vitamin D receptor ligands have potential for the treatment of hyperproliferative diseases and disorders related to the immune system. However, hypercalcemic effects limit their therapeutical uses and call for the development of tissue-selective new analogs. We have designed and synthesized the first examples of 1α,25-dihydroxyvitamin D3 analogs bearing an allenic unit attached to the D ring to restrict the side-chain conformational mobility. The triene system was constructed by a Pd0-mediated cyclization/Suzuki-Miyaura cross-coupling process in the presence of an allenic side chain. The allenic moiety was built through an orthoester-Claisen rearrangement of a propargylic alcohol. The biological activity and structure of (22S)-1α,25-dihydroxy-17,20-dien-24-homo-21-nor-vitamin D3 bound to binding domain of the vitamin D receptor, provide information concerning side-chain conformational requirements for biological activity. 相似文献
152.
Kononenko N. A. Demina O. A. Loza N. V. Dolgopolov S. V. Timofeev S. V. 《Russian Journal of Electrochemistry》2021,57(5):505-518
Russian Journal of Electrochemistry - The limiting diffusion current density in electromembrane systems is theoretically estimated by using refined Pears equation and different model approaches for... 相似文献
153.
Christoph J. Behrens Kateryna Zelena Ralf G. Berger 《Applied biochemistry and biotechnology》2016,179(8):1404-1417
Dye-decolorizing peroxidases (DyPs) from Auricularia auricula-judae, Bjerkandera adusta, Pleurotus ostreatus and Marasmius scorodonius (Basidiomycota) were expressed in Escherichia coli using the cold shock-inducible expression system pCOLD I DNA. Functional expression was achieved without the addition of hemin or the co-expression of any chaperones. The presence or absence of the native signal sequence had a strong impact on the success of the expression, but the effect was not consistent for the different DyPs. While BaDyP and AajDyP were stable at 50 °C, the more thermolabile MsP2 and PoDyp, upon catalytic intervention, lend themselves to more rapid thermal inactivation. The bleaching of norbixin (E 160b) using MsP2 was most efficient at pH 4.0, while BaDyP and AajDypP worked best in the weakly acidic to neutral range, indicating a choice of DyPs for a broad field of applications in different food matrices. 相似文献
154.
Kateryna Bazaka 《Polymer Degradation and Stability》2010,95(6):1123-2961
Owing to the structural flexibility, uncomplicated processing and manufacturing capabilities, plasma polymers are the subject of active academic as well as industrial research. Polymer thin films prepared from non-synthetic monomers combine desirable optical and physical properties with biocompatibility and environmental sustainability. However, the ultimate expediency and implementation of such materials will dependent on the stability of these properties under varied environmental conditions. Polyterpenol thin films were manufactured at different deposition powers. Under ambient conditions, the bulk of ageing occurred within first 150 h after deposition and was attributed to oxidation and volumetric relaxation. Films observed for further 12 months showed no significant changes in thickness or refractive index. Thermal degradation behaviour indicated thermal stability increased for the films manufactured at higher RF powers. Annealing the films to 405 °C resulted in full degradation, with retention between 0.29 and 0.99%, indicating films' potential as sacrificial material. 相似文献
155.
N. A. Kononenko S. V. Dolgopolov N. P. Berezina N. V. Loza S. G. Lakeev 《Russian Journal of Electrochemistry》2012,48(8):857-861
The effect of asymmetry of the voltammetric characteristics is studied on anisotropic composites obtained using the technique of polyaniline matrix synthesis in the surface layer of the MF-4SK membrane. On the basis of studies of the ohmic voltammetric curve section in a series of isomolar HCl-NaCl solutions, independence of the membrane conductivity on the fraction of protons in the solution is established in the case when the modified membrane side is turned towards the counterion flow. In the case of the reverse orientation, the membrane conductivity is changed symbatically at an increase in the proton content in the mixed solution. An explanation of this effect is suggested with account for the regularities of the concentration profile formed in the bilayer membrane under polarization, water decomposition on the inner bipolar boundary, and also a change in the energy state of water in the composite membrane. 相似文献
156.
N. S. Vostrikov V. V. Loza N. A. Ivanova M. S. Miftakhov 《Russian Journal of Organic Chemistry》2010,46(9):1301-1304
The condensation of ethyl 7-(2-oxo-5-formulcyclopentyl)heptanoate by Wittig reaction with the ylide prepared from [(2E)-3-methylhept-2-en-1-yl]triphenylphosphonium bromide afforded ethyl (±)-(13,15-dideoxy)-16-methyl-9-oxoprosta-13(E,Z),15(E)-dienoate as a mixture of two isomers, 2:1. 相似文献
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Viktor Yu. Kramarenko Tetyana A. Shantalil Iryna L. Karpova Kateryna S. Dragan Eleonora G. Privalko Valery P. Privalko Daniel Fragiadakis Polycarpos Pissis 《先进技术聚合物》2004,15(3):144-148
Polyimide (PI) nanocomposites prepared by the in situ generation of crosslinked organosilicon nanophase (ON) through the sol‐gel process were characterized by densities, thermally stimulated depolarization currents and dielectric relaxation spectroscopy. Both a looser molecular packing of PI chain fragments adjacent to the ON and a loose inner structure of the spatial aggregates of ON were assumed to be responsible for a non‐additive decrease of the experimental values of dielectric permittivity for the nanocomposites. The pattern of composition dependence of the apparent dielectric permittivity of the ON suggested a probability of a morphological change around the composition PAAS/MTS = 100/16 (presumably, a sort of percolation transition from small‐size, individual clusters into large‐size, infinite clusters). Thus, PI reinforced with the sol‐gel derived nanophase may have a reasonably good potential as low dielectric permittivity materials. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献