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71.
Shiryaev A. K. Belen´kaya R. S. Shiryaev V. A. Rybakov V. B. Klimochkin Yu. N. 《Russian Chemical Bulletin》2015,64(12):2966-2969
Russian Chemical Bulletin - Methyl adamantane-1-carboxylate and methyl (1-adamantyl)acetate react with acetonitrile in the presence of sodium hydride to give 3-(1-adamantyl)-3-oxopropanenitrile and... 相似文献
72.
73.
M. Violante de Paz Ba´ñez Jose´ A. Aznar Moreno 《Journal of carbohydrate chemistry》2013,32(2):120-140
Biodegradable polymers obtained from renewable natural sources are currently receiving increasing attention because they are an alternative to the traditional petroleum‐based plastics. In the present communication we describe the synthesis of the diol monomers 2,3,4‐tri‐O‐benzyl‐L‐arabinitol (ABnOH) and 2,3,4‐tri‐O‐benzylxylitol (XBnOH), and the diamino monomers 1,5‐diamino‐1,5‐dideoxy‐2,3,4‐tri‐O‐benzyl‐L‐arabinitol (ABnNH 2 ) and 1,5‐diamino‐1,5‐dideoxy‐2,3,4‐tri‐O‐benzylxylitol (XBnNH 2 ), which can be used in the preparation of new potentially biodegradable sugar‐based polymers. As an example, we describe the synthesis and characterization of a polyurethane [PU‐(ABnOH‐HMDI)] and a polyurea [PUR‐(ABnNH2‐HMDI)] by poly addition reaction of ABnOH and ABnNH 2 with 1,6‐hexamethylene diisocyanate. 相似文献
74.
He´ctor J. Sussmann 《Journal of Differential Equations》1979,31(1):31-52
The theory of subanalytic sets is used to prove: If a real analytic control system is completely controllable, then for every point p in the state space there exists a piecewise analytic feedback control that steers every state into p. 相似文献
75.
The aim of this study was to examine the impact of osmotic pressure, regulated by an addition of different NaCl concentrations, on the production parameters and activity of the enzymes involved in the biosynthesis of erythritol from glycerol by Yarrowia lipolytica yeast. In the bioreactor batchcultures, strain A-3 was able to produce from 25.3 g dm?3 to 84.7 g dm?3 of erythritol from 150 g dm?3 of glycerol depending on the initial osmotic pressure. At the osmolality of 4.2 mol kg?3 or higher, a long lag-phase was observed. An enhancement of the production parameters was observed in a culture with the osmotic pressure maintained at an equal level by a step-wise addition of NaCl. The two-hour exposure of strain A-3 cells to 75 g dm?3 of NaCl resulted in decreased activity of glycerol kinase and glycerol-3-phosphate dehydrogenase by about 78 % and 25 %, respectively. The activity of transketolase and erythrose reductase remained unchanged after the salt addition. It was demonstrated that assimilation of glycerol was effective at lower osmotic pressures and that transketolase and erythrose reductase played a significant role in the erythritol formation in Y. lipolytica. 相似文献
76.
Agnieszka Pazik Beata Kami´nska Anna Skwierawska Sandra Nakonieczna Tadeusz Ossowski 《Chemical Papers》2016,70(3):253-264
The synthesis of a new chromogenic N,N′-phenyltetrazole receptor is reported here. The cationbinding properties of this receptor in solution were investigated by naked-eye colour change, electrochemical methods and UV-Vis spectroscopy in various solvents (CH3CN, dimethylsulphoxide (DMSO), DMSO/H2O, CH3CN/H2O and CH3CN/MeOH). In addition, the receptor was used as a sensing material in ion-selective membrane electrodes. The selectivity and sensitivity of these electrodes towards alkali, alkali-earth, transition and heavy metal cations in aqueous solution were tested. The relation between the carrier structure and membrane plasticisers was investigated. 相似文献
77.
Sokolov V. B. Aksinenko A. Yu. Goreva T. V. Epishina T. A. Grigor´ev V. V. Gabrel´yan A. V. Vinogradova D. V. Dubova L. G. Shevtsov P. N. Shevtsova E. F. Bachurin S. O. 《Russian Chemical Bulletin》2016,65(5):1346-1353
Russian Chemical Bulletin - Earlier unknown conjugates of carbazoles and γ-carbolines were obtained by the reaction of 3,6-substituted 9-oxiranylmethylcarbazoles and 2,8-substituted... 相似文献
78.
Sanina N. A. Kozub G. I. Kondrat´eva T. A. Terent´ev A. A. Mumyatova V. A. Barzilovich P. Yu. Ovanesyan N. S. Aldoshin S. M. 《Russian Chemical Bulletin》2017,66(9):1706-1711
Russian Chemical Bulletin - A preparative procedure was developed for the synthesis of new binuclear tetranitrosyl iron complex of the “μ-S” structural type, [Fe2(SC6H4NO2)2(NO)4]... 相似文献
79.
N. A. Zefirov E. V. Nurieva Yu. A. Pikulina A. V. Ogon´kov B. Wobith S. A. Kuznetsov O. N. Zefirova 《Russian Chemical Bulletin》2017,66(8):1503-1509
Adamantaneacetic and adamantanecarboxylic acid esters containing 3-hydroxy-4-methoxybenzyl, 3,4,5-trimethoxybenzyl, or 5-(hydroxymethyl)-2-methoxyphenyl groups were synthesized as unusual analogs of natural antitumor and anti-tubulin agents combretastatin A-4 and 2-methoxyestradiol. The compounds were found to possess noticeable cytotoxicity to epithelial human carcinoma cell line A549 (EC50 = 4.3—81 μmol L–1). An ability to cause complete depolymerization of microtubule network of A549 cells was demonstrated for 5-(hydroxymethyl)-2-methoxyphenyl adamantan-1-ylacetate (6a) at a concentration of 100 μmol L–1. Ester 6a belongs to a new structural type, which is unusual for the ligands of the tubulin colchicine domain, and is an interesting lead compound for further structural optimization. 相似文献
80.
A. A. Titov A. F. Smol´yakov A. N. Rodionov I. D. Kosenko E. A. Guseva Ya. V. Zubavichus P. V. Dorovatovskii O. A. Filippov E. S. Shubina 《Russian Chemical Bulletin》2017,66(9):1563-1568
New tri- and tetranuclear macrocyclic silver(i) and copper(i) 3-ferrocenyl-5-(trifluoromethyl)pyrazolates were prepared: [{(3-((η5-C5H4)Fe(η5-C5H5))-5-(CF3)-Pz}M]3 (M = Cu (1), Ag (2)) and [{(3-(( η5-C5H4)Fe(η5-C5H5))-5-(CF3)-Pz}Cu]4 (3). The structures of compounds were established by X-ray diffraction analysis. In the crystalline state, a planar trinuclear silver-containing macrocycliс pyrazolate and a saddle-shaped tetranuclear copper-containing macrocycle are formed. The introduction of a bulky substituent, ferrocene, into the pyrazole ligand results in complete shielding of the acidic metal sites, which precludes the coordination of base molecules. 相似文献