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1.
E. E. Sirotkina A. I. Khlebnikov N. A. Domina A. V. Domin 《Russian Physics Journal》2004,47(11):1134-1138
Intensities of principal diffraction maxima for a phase reflection diffraction grating with a rectangular groove profile were calculated by the Fresnel method, using a special algorithm. The procedure under consideration enables us to perform high-efficiency calculations of diffracted-beam characteristics and can be used extensively to optimize diffraction-grating parameters.__________This revised version was published online in May 2005 with a correction on affiliation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 38–41, November 2004. 相似文献
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M. S. Novikov A. F. Khlebnikov M. A. Egarmin J. Kopf R. R. Kostikov 《Russian Journal of Organic Chemistry》2004,40(10):1493-1499
Azomethine ylides generated by reaction of difluorocarbene with N-alkyl- and N-arylimines derived from benzaldehyde and benzophenone react with N-benzylidenebenzenesulfonamide in a regioselective fashion, yielding the corresponding imidazolidin-4-ones via 1,3-dipolar cycloaddition at the C=N bond. Ylides generated from benzaldehyde imines give rise to mixtures of stereoisomeric 2,5-diphenyl-1-(phenylsulfonyl)-imidazolidin-4-ones, the cis isomer prevailing.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1542–1548.Original Russian Text Copyright © 2004 by Novikov, Khlebnikov, Egarmin, Kopf, Kostikov. 相似文献
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M. S. Novikov A. F. Khlebnikov M. V. Shevchenko R. R. Kostikov D. Vidovic 《Russian Journal of Organic Chemistry》2005,41(10):1496-1506
2-Fluoro-4,5-dihydropyrrole-3,4-dicarboxylic acid derivatives were obtained by reaction of difluorocarbene with N-substituted ketone imines in the presence of fumaronitrile, maleonitrile, or dimethyl maleate. The reaction involves intermediate formation of azomethine ylides and their subsequent cycloaddition at the double bond. 11H-Dibenz[b,e]azepine and 3,4-dihydroisoquinolines react with difluorocarbene in the presence of fumaronitrile to give fluoro-substituted dibenzo[c,f]pyrrolo[1,2-a]azepine and pyrrolo[2,1-a]-isoquinoline derivatives. Treatment of 2-fluoro-4,5-dihydropyrrole-3,4-dicarbonitrile with amines and alkoxides affords the corresponding 2-amino- and 2-alkoxy derivatives, while its reactions with hydrazine hydrate and benzimidamide lead to formation of substituted pyrrolo[2,3-c]pyrazole and pyrrolo[2,3-d]-pyrimidine derivatives. 相似文献
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Khlebnikov A. F. Novikov M. S. Kusei E. Yu. Kopf J. Kostikov R. R. 《Russian Journal of Organic Chemistry》2003,39(4):559-573
Esters of (2,2-diaryl-3,3-dichloroaziridin-1-yl)acetic acid prepared from glycine derivatives under alkylation conditions afford esters of 2-[N-alkyl-N-(2,2-diaryl-1-cyanovinyl)amino]-3,3-diarylacrylic acid in 20-40% yield. The reaction resulting in these compounds proceeds through a cascade of 3-chloro-2-azadiene and ylide intermediates. 3-Chloro-2-azadienes originating from (2,2-diaryl-3,3-dichloroaziridin-1-yl)acetates react with primary and secondary amines at the carbon atom of imine group providing ketenimines which undergo ketenimine-nitrile rearrangement or fragmentation. The other bases (KOH, MeONa, DBU) effect dehydrochlorination of the mentioned 3-chloro-2-azadienes giving nitrile-ylides which are trapped by nucleophilic reagents. The 3-chloro-2-azadiene obtained from methyl (2,2-diaryl-3,3-dichloroaziridin-1-yl)acetate and DBU was relatively stable and was isolated as an individual compound. (2,2-diaryl-3,3-dichloroaziridin-1-yl)propionates behave as nonfunctionalized dichloroaziridines. 相似文献
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V. I. Khlebnikov 《Russian Physics Journal》1976,19(3):359-364
A series of solutions of Einstein's equations with term is found; it describes the gravitational field of quasistationary concentrated systems containing electric and magnetic charges. The metrics are of Petrov type D and have rotation and expansion. The solutions are interpreted physically. In this, the second part of the paper the complete system of Newman — Penrose equations is integrated under the formulated assumptions.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 118–123, March, 1976.I am also grateful to Yu. S. Vladimirov (M. V. Lomonosov Moscow State University) for his interest in the work. 相似文献
7.
Igor A. Schepetkin Gulmira
zek Temel
zek Liliya N. Kirpotina Andrei I. Khlebnikov Mark T. Quinn 《Molecules (Basel, Switzerland)》2022,27(15)
Grindelia squarrosa (Pursh) Dunal is used in traditional medicine for treating various diseases; however, little is known about the immunomodulatory activity of essential oils from this plant. Thus, we isolated essential oils from the flowers (GEOFl) and leaves (GEOLv) of G. squarrosa and evaluated the chemical composition and innate immunomodulatory activity of these essential oils. Compositional analysis of these essential oils revealed that the main components were α-pinene (24.7 and 23.2% in GEOFl and GEOLv, respectively), limonene (10.0 and 14.7%), borneol (23.4 and 16.6%), p-cymen-8-ol (6.1 and 5.8%), β-pinene (4.0 and 3.8%), bornyl acetate (3.0 and 5.1%), trans-pinocarveol (4.2 and 3.7%), spathulenol (3.0 and 2.0%), myrtenol (2.5 and 1.7%), and terpinolene (1.7 and 2.0%). Enantiomer analysis showed that α-pinene, β-pinene, and borneol were present primarily as (−)-enantiomers (100% enantiomeric excess (ee) for (−)-α-pinene and (−)-borneol in both GEOFl and GEOLv; 82 and 78% ee for (−)-β-pinene in GEOFl and GEOLv), while limonene was present primarily as the (+)-enantiomer (94 and 96 ee in GEOFl and GEOLv). Grindelia essential oils activated human neutrophils, resulting in increased [Ca2+]i (EC50 = 22.3 µg/mL for GEOFl and 19.4 µg/mL for GEOLv). In addition, one of the major enantiomeric components, (−)-borneol, activated human neutrophil [Ca2+]i (EC50 = 28.7 ± 2.6), whereas (+)-borneol was inactive. Since these treatments activated neutrophils, we also evaluated if they were able to down-regulate neutrophil responses to subsequent agonist activation and found that treatment with Grindelia essential oils inhibited activation of these cells by the N-formyl peptide receptor 1 (FPR1) agonist fMLF and the FPR2 agonist WKYMVM. Likewise, (−)-borneol inhibited FPR-agonist-induced Ca2+ influx in neutrophils. Grindelia leaf and flower essential oils, as well as (−)-borneol, also inhibited fMLF-induced chemotaxis of human neutrophils (IC50 = 4.1 ± 0.8 µg/mL, 5.0 ± 1.6 µg/mL, and 5.8 ± 1.4 µM, respectively). Thus, we identified (−)-borneol as a novel modulator of human neutrophil function. 相似文献
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G. N. Knyazheva M. G. Itkis S. V. Khlebnikov E. M. Kozulin V. G. Lyapin V. A. Rubchenya W. Trzaska 《Physics of Particles and Nuclei Letters》2008,5(1):21-28
The mass-energy and angular distributions of binary fissionlike fragments produced in the reactions 44Ca + 206Pb and 64Ni + 186W, leading to the same compound nucleus 250No, have been measured at excitation energies of 30 and 40 MeV. The presence of the quasifission component was observed for both systems. But in the case of the 64Ni ion, the quasifission process dominates, while in the case of the 44Ca ion, the main process is the fusion-fission of compound nucleus 250No. From the angular distributions of reaction fragments, the time scales were found for quasifission and fusion-fission for both reactions. 相似文献
10.
de Meijere A Khlebnikov AF Kostikov RR Kozhushkov SI Schreiner PR Wittkopp A Yufit DS 《Angewandte Chemie (International ed. in English)》1999,38(23):3474-3477
A remarkably high specific rotation, even at 589 nm, is shown by (M)-1, the first enantiomerically pure unbranched [4]triangulane, although it has no chromophore that would lead to any significant absorption above 200 nm. This outstanding rotatory power is in line with a helical arrangement of its sigma bonds, as confirmed by high-level computations. Thus, it is appropriate to call (M)-1 a "sigma-[4]helicene", the first sigma-bond analogue of the aromatic [n]helicenes. 相似文献