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101.
Shubina LK Makarieva TN Dyshlovoy SA Fedorov SN Dmitrenok PS Stonik VA 《Natural product communications》2010,5(12):1881-1884
Three new aaptamine-type alkaloids, 2,3-dihydro-2,3-dioxoaaptamine (1), 6-(N-morpholinyl)-4,5-dihydro-5-oxo-demethyl(oxy)aaptamine (2) and 3-(methylamino)demethyl(oxy)aaptamine (3), along with known aaptamines were isolated from the sponge Aaptos sp. Their structures were determined on the basis of detailed analysis of their 1D and 2D NMR spectroscopic and mass spectral data. The isolated compounds induced apoptosis in human leukemia THP-1 cells. 相似文献
102.
Pavel A. Dub Natalia V. Belkova Dr. Oleg A. Filippov Dr. Jean‐Claude Daran Dr. Lina M. Epstein Prof. Agustí Lledós Prof. Elena S. Shubina Prof. Rinaldo Poli Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(1):189-201
Low‐temperature (200 K) protonation of [Mo(CO)(Cp*)H(PMe3)2] ( 1 ) by Et2O ? HBF4 gives a different result depending on a subtle solvent change: The dihydrogen complex [Mo(CO)(Cp*)(η2‐H2)(PMe3)2]+ ( 2 ) is obtained in THF, whereas the tautomeric classical dihydride [Mo(CO)(Cp*)(H)2(PMe3)2]+ ( 3 ) is the only observable product in dichloromethane. Both products were fully characterised (νCO IR; 1H, 31P, 13C NMR spectroscopies) at low temperature; they lose H2 upon warming to 230 K at approximately the same rate (ca. 10?3 s?1), with no detection of the non‐classical form in CD2Cl2, to generate [Mo(CO)(Cp*)(FBF3)(PMe3)2] ( 4 ). The latter also slowly decomposes at ambient temperature. One of the decomposition products was crystallised and identified by X‐ray crystallography as [Mo(CO)(Cp*)(FH???FBF3)(PMe3)2] ( 5 ), which features a neutral HF ligand coordinated to the transition metal through the F atom and to the BF4? anion through a hydrogen bond. The reason for the switch in relative stability between 2 and 3 was probed by DFT calculations based on the B3LYP and M05‐2X functionals, with inclusion of anion and solvent effects by the conductor‐like polarisable continuum model and by explicit consideration of the solvent molecules. Calculations at the MP4(SDQ) and CCSD(T) levels were also carried out for calibration. The calculations reveal the key role of non‐covalent anion–solvent interactions, which modulate the anion–cation interaction ultimately altering the energetic balance between the two isomeric forms. 相似文献
103.
104.
E. M. Kozinets G. A. Silantyev N. V. Belkova E. S. Shubina R. Poli E. Manoury 《Russian Chemical Bulletin》2013,62(3):751-757
Rhodium complexes with the planar chiral phosphinoferrocenyl thioether ligands [Rh(P,SR)(diene)X] (R = Me, But, Ph, Bn, diene is cyclooctadiene (COD) or norbornadiene (NBD), X = Cl, BF4) catalyze hydrogenation of ketones, imines, and heteroaromatic compounds; in the case of acetophenone, the enantioselectivity reached 60% ee. Similar iridium complexes demonstrate a good activity in the hydrogenation of imines, the maximal enantioselectivity in the case of N-phenyl-N-(1-phenylethylidene)amine was about 40% ee. 相似文献
105.
Yurchenko R. I. Pogrebova I. S. Pilipenko T. N. Shubina T. E. 《Russian Journal of Applied Chemistry》2004,77(7):1117-1120
The inhibiting effect of N-phenacylpyridinium bromides with the amide group in the pyridine ring on corrosion of carbon steel in 3 M sulfuric acid is studied. A relationship between the nature of substituents at the amide group and the corrosion-protective properties of the compounds studied is revealed. Compounds demonstrating high protection efficiency in acid solutions at elevated temperatures are found. 相似文献
106.
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108.
Gaidai A. V. Cherenkova O. A. Levandovskii I. A. Shubina T. E. 《Russian Journal of Organic Chemistry》2010,46(5):765-767
Russian Journal of Organic Chemistry - 相似文献
109.
Shubina LK Makarieva TN Denisenko VA Dmitrenok AS Guzii AG Dmitrenok PS Stonik VA 《Natural product research》2006,20(13):1183-1186
A new diketosteroid, 5alpha-ergost-24(28)-ene-3,6-dione (1), has been isolated from the sponge Geodinella robusta. Its structure was determined by combined spectroscopic methods and chemical evidence. 相似文献
110.
Mizerov A. M. Kukushkin S. A. Sharofidinov Sh. Sh. Osipov A. V. Timoshnev S. N. Shubina K. Yu. Berezovskaya T. N. Mokhov D. V. Buravlev A. D. 《Physics of the Solid State》2019,61(12):2277-2281
Physics of the Solid State - The effect of the inversion of polarity in gallium nitride layers from the N-polar GaN layer to the Ga-polar GaN layer was discovered during the sequential growth of... 相似文献