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L. K. Kibardina A. V. Trifonov Yu. I. Ivanova M. A. Pudovik E. M. Pudovik A. R. Burilov 《Russian Journal of General Chemistry》2018,88(1):41-47
The reaction of pyridoxal with 2,4-dihydroxybenzaldehyde in a hydrochloric acid solution gave 1-(5-formyl-2,4-dihydroxyphenyl)-7-hydroxy-6-methyl-1,3-dihydrofuro[3,4-c]pyridin-5-ium chloride. Treatment of the latter with sodium hydride in ethanol afforded a free aldehyde in 85% yield. A series of azomethines and imidazolidines was obtained by reacting the obtained aldehyde with various amines and diamines. 相似文献
53.
E. A. Chugunova V. A. Samsonov A. S. Gazizov A. R. Burilov M. A. Pudovik O. G. Sinyashin 《Russian Chemical Bulletin》2018,67(11):1955-1970
The review presents and summarizes comprehensive data starting from 2006 on the synthesis of mono- and di-N-oxides of 2H-benzimidazoles and their chemical properties. Especial attention was paid to the chemical transformations of 2H-benzimidazole 1,3-dioxides upon heating to give 3H-2,1,4-benzoxadiazine 4-oxides and 2H-benzimidazole mono-N-oxides. The biological activity of compounds was covered. 相似文献
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L. I. Vagapova A. V. Smolobochkin A. S. Gazizov A. R. Burilov A. A. Bogdanov M. A. Pudovik O. G. Sinyashin 《Russian Journal of Organic Chemistry》2016,52(9):1335-1338
Adenosine derivatives containing a 2,2-bis(diethoxyphosphoryl)ethyl or 2,2-diphosphonoethyl group on the amino nitrogen atom were synthesized for the first time by reaction of 5′-chloro-5′-deoxy- and 5′-hydroxy-2′,3′-isopropylideneadenosine with tetraethyl ethene-1,1-diylbis(phosphonate) or tetrakis(trimethylsilyl) ethene-1,1-diylbis(phosphonate). 相似文献
56.
E. M. Kasymova A. R. Burilov N. A. Mukmeneva S. V. Bukharov G. N. Nugumanova M. A. Pudovik A. V. Chernova R. R. Shagidullin A. I. Konovalov 《Russian Journal of General Chemistry》2007,77(3):458-468
A method for the synthesis of new calix[4]resorcinols tetra-3,5-di-tert-butyl-4-hydroxybenzyl derivatives is developed. Their interaction with methyldichlorophosphonate, dimethyldichlorosilane in the presence of a base leads to formation of organophosphorus-organosilicon cavitands. Acetylation of hydroxybenzylated calix[4]resorcinols with acetic anhydride leads to products of either incomplete or full acetylation depending on experimental conditions. 相似文献
57.
非线性涡黏性系数模型和代数应力模型联系了线性涡黏性系数湍流模型和完整的微分
雷诺应力模型.随着它们受到日益关注,其形式也越来越多样化.本篇综述的目的是对这些模
型加以总结并比较它们之间的共同点及不同之处,指出它们与完整微分雷诺应力模型之间的
关系,以及相对于线性涡黏性系数模型而言它们在预报流场上所具有的优势. 相似文献
58.
Nugumanova G. N. Tagasheva R. G. Bukharov S. V. Krivolapov D. B. Litvinov I. A. Syakaev V. V. Mukmeneva N. A. Burilov A. R. 《Russian Chemical Bulletin》2009,58(9):1934-1938
Isatin acylhydrazones with sterically hindered phenolic fragments were obtained. Their structures were determined using 1D
and 2D 1H and 13C NMR spectroscopy and X-ray diffraction. The products synthesized by condensation of isatin and 1-(3,5-di-
tert-butyl-4-hydroxybenzyl)-l H-indole-2,3-dione with 3-(3,5-di- tert-butyl-4-hydroxyphenyl)propiono-hydrazide exist as E- and Z-isomers about the C=N bond. E— Z isomerization takes place in boiling ethanol. The E-isomer of the condensation product from isatin and 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionohydrazide was structurally characterized using X-ray diffraction: this isomer is a cis-conformer about the amide group and has a E-configuration about the N—N bond. According to data on the concentration dependence of the signals for the NH protons in
the 1H NMR spectra, the acylhydrazones obtained are stabilized in solution by intra-and intermolecular hydrogen bonding. 相似文献
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