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81.
A. P. Novikova N. M. Perova L. G. Egorova E. I. Bragina 《Chemistry of Heterocyclic Compounds》1991,27(6):666-668
2-Amino-5-aryl(pyridyl)-6H-1,3,4-thiadiazines ana isomeric 2-hydrazino-4-aryl(pyridyl)thiazoles, the ratio of which depends on the reaction conditions, were obtained by the reaction of substituted phenacyl bromides and bromoacetylpyridines with thiosemicarbazide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 843–846, June, 1991. 相似文献
82.
I. V. Ledenyova P. A. Kartavtsev Kh. S. Shikhaliev A. Yu. Egorova 《Russian Journal of Organic Chemistry》2016,52(9):1316-1321
Coupling of 3-alkyl-4-aryl-1H-pyrazole-5-diazonium chlorides with methylene-active methyl phenacyl sulfones afforded new pyrazolo[5,1-c][1,2,4]triazine derivatives via cyclization of the corresponding intermediate 1-aryl-2-(hetarylhydrazinylidene)-2-(methanesulfonyl)ethanones. The reactivity of the methanesulfonyl group on C3 of pyrazolo[5,1-c][1,2,4]triazines toward some nucleophiles was studied. 相似文献
83.
Sharutin V. V. Sharutina O. K. Egorova I. V. Pavlushkina I. I. Pushilin M. A. Gerasimenko A. V. 《Russian Journal of Coordination Chemistry》2004,30(1):23-26
A reaction of triphenylbismuth with 2,4,6-tribromophenol and hydrogen peroxide (molar ratio 1 : 2 : 1) in ether affords triphenylbismuth bis(2,4,6-tribromophenoxide). The complex obtained was structurally characterized by X-ray diffraction analysis. The coordination polyhedron of the Bi atom is a trigonal bipyramid with axial aroxy groups. The Bi–C and Bi–O bond lengths are 2.202(4), 2.203(4), 2.212(4) and 2.241(3), 2.245(3) Å, respectively. The intramolecular Bi···Br(1,4) contacts are 3.629(1) and 4.077(1) Å, respectively. 相似文献
84.
B. M. Krasovitskii N. P. Egorova L. Sh. Afanasiadi I. V. Lysova V. K. Polyakov S. V. Tsukerman 《Chemistry of Heterocyclic Compounds》1982,18(5):461-465
A number of new organic luminophores was synthesized by PO olefination from 2- (4-bromomethylphenyl)-5-phenyloxazole and -1,3,4-oxadiazole and various heterocyclic aldehydes that contain a furan ring. The absorption and fluorescence spectra of the products in toluene, as well as their scintillation characteristics, were measured. The effect of the electronic nature of the substituents on the spectral-luminescence properties of the luminophores is discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 617–621, May, 1982. 相似文献
85.
I. N. Polyakova O. A. Egorova V. S. Sergienko L. Yu. Tarasova V. V. Davydov 《Crystallography Reports》2011,56(2):270-273
The crystal structure of 2-[(4-nitrophenyl)carbonyl]cyclohex-1-ene-1-yl 4-nitrobenzoate is studied (T = 173 K, R1 = 0.0354 for 2713 observed reflections). This crystal is orthorhombic, a = 7.8367(8) Å, b = 9.6082(10) Å, c = 23.856(3) Å, V = 1796.3(3) Å3, space group P212121, and Z = 4. The molecule has a folded configuration, which is stabilized by π-π interactions between its two parts. A system of intermolecular C-H...O hydrogen bonds (H...O, 2.44–2.67 Å; CHO angles 122°–169°) and intramolecular C-H...O contacts closing five-membered cycles (H...O, 2.42–2.59 Å; CHO angles 96°–102°) are formed in the structure. 相似文献
86.
Egorova N. I. Konyushenko I. O. Nemets V. M. Peganov S. A. 《Optics and Spectroscopy》2020,128(4):553-561
Optics and Spectroscopy - The features and possibilities of absorption molecular spectroscopy of complex mixtures of organic compounds have been studied by the example of fractions of thermal... 相似文献
87.
88.
Dr. Ksenia S. Egorova Alexey S. Galushko Prof. Valentine P. Ananikov 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22480-22489
In this Essay, we present a critical analysis of two common practices in modern chemistry—that is, of using speculations about the “greenness” and “nontoxicity” of developed synthesis procedures and of a priori labelling various compounds derived from natural sources as being environmentally safe. We note that every organic molecule that contains functional groups should be biologically active. Thus, analysis of the particular greenness and the potential environmental impact of a given chemical process should account for the biological activity of all its components in a measureable (rather than empirical) way. We highlight the necessity of clarifying discussions on biological activity and toxicity and propose possible ways of introducing tox-Profiles as a reliable overview of the overall toxicity of chemical reactions. 相似文献
89.
Schastlivtsev V. M. Khlebnikova Yu. V. Rodionov D. P. Egorova L. Yu. 《Doklady Physics》2019,64(5):229-232
Doklady Physics - Electron back-scattering diffraction shows that a package structure consisting of colonies of tetragonal lamella plates is formed when cooled below the temperature of the... 相似文献
90.
Temperature dependences of dielectric constant, amplitude of the third harmonic and heat capacity for the organic ferroelectric of diisopropylammonium iodide (C6H16NI) have been investigated. The measurements were carried out through heating and cooling cycles in the range of 300–400?K. It was found that upon the first heating, only one phase transition occurred without the presence of the ferroelectric phase. For samples preheated over 420?K, two phase transitions at 363 and 378?K appeared in the heating process, and the ferroelectric state was also observed between them. Upon cooling, the ferroelectric phase was detected in the range of lower 361?K and persisted up to room temperature. 相似文献