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91.
92.
本文利用荧光光谱和园二色光谱了新开花粉蛋白的盐酸胍去折叠过程。结果显示:新开花粉蛋白的盐酸胍去折叠是一个只包含天然蛋白和变性终态的二态过程,与已经报道的天花粉蛋白的盐酸胍去折叠的过程不同。 相似文献
93.
E. V. Trofimova A. N. Fedotov S. S. Mochalov Yu. S. Shabarov N. S. Zefirov 《ChemInform》2001,32(29):148-148
94.
95.
Olga N. Zefirova Evgeniya V. Nurieva Birgit Wobith Vladimir V. Gogol Nikolay A. Zefirov Andrei V. Ogonkov Dmitrii V. Shishov Nikolay S. Zefirov Sergei A. Kuznetsov 《Molecular diversity》2017,21(3):547-564
Tubuloclustin [N-(7-adamant-2-yloxy-7-oxoheptanoyl)-N-deacetylcolchicine], a highly cytotoxic anti-tubulin compound is known for its ability to promote microtubule disassembly followed by the formation of tubulin clusters of unique morphology. Three series of antimitotic agents related to tubuloclustin were designed and synthesized in order to enhance the molecular diversity of “tubuloclustin-like” family of compounds. The series of compounds with modified adamantane moiety was highly potent in cytotoxic effect on human lung carcinoma A549 cells (EC50 = 6–400 nM) and was active in affecting the microtubule arrays and induction of strong tubulin clusterization. In two other sets of compounds, the colchicine moiety of tubuloclustin was replaced by podophyllotoxin or combretastatin A-4. All combretastatin A-4 derivatives displayed noticeable cytotoxic activity (\(\hbox {EC}50=0.8{-}1.6\,\upmu \hbox {M}\)) but their effect on microtubules depended on the position of the linker attachment. Podophyllotoxin derivatives were also toxic to A549 cells (\(\hbox {EC}50=0.38{-}0.50\,\upmu \hbox {M}\)) and caused both microtubule depolymerization and some tubulin clustering. The data obtained gave additional evidence that the whole panel of C7-colchicine, podophyllotoxin and combretastatin derivatives could manifest clustering effect, and the strength of this effect correlated with cytotoxic activity of the compounds. 相似文献
96.
E. D. Matveeva T. A. Podrugina I. N. Kolesnikova A. A. Borisenko N. S. Zefirov 《Russian Chemical Bulletin》2009,58(1):119-125
6h-Aminophosphonates containing alicyclic, aromatic, and heterocyclic fragments were obtained in high yields by the Kabachnick—Fields
reaction of the corresponding carbonyl compounds with 2-, 3- and 4-aminopyridines and diethyl phosphite using tetra- tert-butyl- phthalocyanine aluminum chloride as the catalyst. 2-, 3-, 4-Aminopyridines were found to vary in their reactivity
with ketones and diethyl phosphite in the catalytic three-component one-pot process. 相似文献
97.
I. S. Veselov I. V. Trushkov N. S. Zefirov G. V. Grishina 《Russian Journal of Organic Chemistry》2009,45(7):1050-1060
trans-4-Amino-1-benzyl-3-hydroxypiperidines were synthesized by regio- and stereoselective amination of a series of 1-benzyl-3,4-epoxypiperidines with primary and secondary aliphatic, aromatic, and heterocyclic amines in the presence of lithium perchlorate. The regio- and stereoselectivity of the amination process is ensured by specific activation of the oxirane ring in epoxypiperidine derivatives. Lithium cation is coordinated simultaneously at the piperidine nitrogen atom and oxirane oxygen atom, which leads to greater extension of the C4-O bond as compared to C3-O, so that nucleophilic attack is directed at the C4 atom of the piperidine ring. 相似文献
98.
S. S. Mochalov A. N. Fedotov E. V. Trofimova N. S. Zefirov 《Russian Journal of Organic Chemistry》2016,52(4):503-512
Benzyl alcohols formed by the reduction of benzaldehydes, alkyl aryl ketones, and benzophenones with sodium tetrahydridoborate in alcohols undergo in situ etherification with the solvent in the presence of a catalytic amount of HCl. Thus the process may be regarded as one-pot transformation of carbonyl compounds into the corresponding benzyl ethers. The yields of ethers depend on the substituent nature in the aromatic fragment of the initial carbonyl compound and on the alcohol used as reduction medium. 相似文献
99.
E. D. Matveev T. A. Podrugin I. V. Sharutin N. S. Zefirov 《Russian Chemical Bulletin》2012,61(2):386-391
Reaction of diethyl phosphite with semicarbazones, thiosemicarbazones, carbonohydrazones, and oxalyldihydrazones of aliphatic and carbocyclic ketones catalyzed by [tetra(tert-butyl)phthalocyanine]aluminum chloride resulted in hydrophosphorylation of the C=N bonds of hydrazones under study. 相似文献
100.
Review of nanofluids for heat transfer applications 总被引:2,自引:0,他引:2
Saeid Vafaei 《中国颗粒学报》2009,7(2)
Research on nanofluids has progressed rapidly since its enhanced thermal conductivity was first repotted about a decade ago,though much controversy and inconsistency have been reported,and insufficient understanding of the formulation and mechanism of nanofluids further limits their applications.This work presents a critical review of research on heat transfer applications of nanofluids with the aim of identifying the limiting factors so as to push forward their further development. 相似文献