排序方式: 共有45条查询结果,搜索用时 62 毫秒
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P. B. Terent'ev T. P. Moskvina L. V. Moshentseva A. N. Kost 《Chemistry of Heterocyclic Compounds》1970,6(4):460-464
The action of diazomethane on -ethynylpyridines substituted in the pyridine ring or analogous compounds with an alkyl group in place of the acetylenic hydrogen atom has given 3-(pyridin-3-yl)pyrazoles. When the acetylenic hydrogen atom is replaced by an electron-accepting carboxyl group, the polarization of the triple bond interferes with the reaction, which then leads to a mixture of 3- and 4-(pyridin-3-yl)pyrazoles with the simultaneous methylation of the nitrogen of the pyrazole ring. 相似文献
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L. A. Pesin V. P. Andreichuk V. M. Morilova I. V. Gribov N. A. Moskvina V. L. Kuznetsov S. E. Evsyukov O. V. Koryakova A. D. Mokrushin E. V. Egorov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2013,7(3):446-451
Under the action of ionizing radiation on a PVDF film, fluorine and hydrogen atoms bound to its linear carbon chain with single chemical bonds detach. Free atoms and HF molecules diffuse toward the film surface and escape from it. As a result of irradiation of the sample surface, a fluorine concentration depth profile arises. The fluorine distribution in the PVDF films subjected to long-term X-ray exposure was studied using X-ray photoelectron spectroscopy and Rutherford backscattering spectroscopy. Both methods yield close values of the fluorine concentration at a depth of ~10 nm. 相似文献
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Malets Yehor S. Moskvina Viktoriia S. Grygorenko Oleksandr O. Brovarets Volodymyr S. 《Chemistry of Heterocyclic Compounds》2019,55(11):1007-1012
Chemistry of Heterocyclic Compounds - This minireview highlights known methods for the synthesis of azachromones and azachromanones, including the earliest and the latest examples of their... 相似文献
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Oleksandr P. Demchuk Bohdan V. Bobovskyi Bohdan V. Vashchenko Dr. Oleksandr V. Hryshchuk Artem Skreminskyi Dr. Anton V. Chernykh Dr. Viktoriia S. Moskvina Dr. Olga V. Hordiyenko Prof. Dr. Dmitriy M. Volochnyuk Prof. Dr. Oleksandr O. Grygorenko 《European journal of organic chemistry》2023,26(24):e202300292
Synthesis and physicochemical characterization of all possible cis- and trans-1,3-disubstituted cyclobutane-derived amines and carboxylic acids bearing mono-, di- and trifluoromethyl groups at the C-3 position is disclosed. Tetramethylammonium fluoride (TMAF)- or morpholinosulfur trifluoride (Morph-DAST)-mediated nucleophilic fluorination of appropriate cis- and trans-diastereomeric substrates was used as the key step for the preparation of CH2F- and CHF2-substituted derivatives. To obtain the corresponding cis- and trans-isomeric CF3-substituted derivatives, resolution of known 3-(trifluoromethyl)cyclobutanecarboxylic acid (obtained as a mixture of diastereomers) was applied. The proposed procedures were suitable for the preparation of corresponding fluoroalkyl-substituted cyclobutane-derived amines and carboxylic acids on up to 50 g scale. All 12 building blocks obtained were characterized by measuring dissociation constants (pKa) and lipophilicities (LogP, for model derivatives) to evaluate the effect of the fluoroalkyl substituents on their physicochemical properties relevant to further drug discovery applications. 相似文献
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Shablykina O. V. Shilin S. V. Moskvina V. S. Ishchenko V. V. Khilya V. P. 《Chemistry of Natural Compounds》2021,57(2):209-229
Chemistry of Natural Compounds - Approaches to the synthesis of isocoumarins and 3,4-dihydroisocoumarins containing natural or synthetic amino-acid fragments are reviewed. Most attention is paid to... 相似文献
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Margamov I. G. Evsyukov S. E. Pesin L. A. Baitinger E. M. Semochkin P. S. Gribov I. V. Moskvina N. A. Kuznetsov V. L. 《Russian Journal of Applied Chemistry》2003,76(1):124-127
IR and X-ray photoelectron spectra of the products of chemical carbonization of polyvinylidene fluoride were recorded and discussed. 相似文献
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A. E. Varfolomeev D. Yu. Godovskii G. A. Kapustin A. V. Volkov M. A. Moskvina 《JETP Letters》1998,67(1):39-42
Conducting polymer composites based on Fe3O4 nanocrystals in a polyvinyl alcohol matrix are synthesized. The current-voltage characteristics, the magnetization, and the
magnetoresistance of the nanocomposites are investigated, and a giant negative magnetoresistance is observed. The decrease
in the resistance at room temperature is found to reach 10% in a 10 kOe field.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 1, 37–40 (10 January 1998) 相似文献
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S.S. Chebotaryov A.A. Volegov L.A. Pesin S.E. Evsyukov N.A. Moskvina I.V. Gribov V.L. Kuznetsov 《Physica E: Low-dimensional Systems and Nanostructures》2007,36(2):184-189
Modifications of the photoelectron and C KVV Auger spectra during the long-term surface degradation of partially crystalline PVDF under simultaneous soft X-ray and electron followed by ion irradiation are reported. Deep radiative carbonization brings about the formation of carbynoid structures (chain-like carbon) in the surface, while the number of interchain cross-links is insignificant. As a result, the shape of the electron emission spectra of carbon in the carbonized sample essentially differs from that of graphite and PVDF. The ion bombardment of the carbonized sample destroys one-dimensional structure due to the formation of cross-links. Thus, carbon atoms transit into sp2-hybrid state and, therefore, the photoelectron and Auger spectra show features characteristic for microcrystalline graphite. 相似文献