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1.
The fine-structure parameters of a series of configurations of the first ion of indium and the gyromagnetic ratios in intermediate coupling are calculated by a semiempirical method in the single-configuration approximation. 相似文献
2.
The interaction of 3,5-diamino-4-nitropyrazole with such electrophilic reagents as acetic anhydride, dimethylformamide acetal, orthoformic ester, and ketones has been studied. Derivatives of pyrazolol[1,5-a]pyrimidines were formed on reaction with 1,3-diketones and some of their properties have been studied.Center for Drug Chemistry, All-Russian Chemical and Pharmaceutical Research Institute (VNIKhFI), Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 329–335, March, 1997. 相似文献
3.
N-Acylalkylation of neutral and anionic N-nucleophiles with α-halocarbonyl compounds was investigated by quantum chemical methods
in terms of the density functional theory and by experimental methods for 2,3-dihydroimidazo[2,1-b]quinazolin-1(10)H-5-one, its N-anion, and simpler model structures. High reactivity of these reagents is determined primarily by stabilization
of transition states (TS) by bridge bonds involving halogen or nitrogen atoms rather than by conjugation, as has been commonly
accepted. Bridged TS are formed by both the substitution mechanism S
N
2 and the addition-elimination mechanism. α-Haloalkyl-substituted zwitterions, which are potential intermediates of stepwise
N-acylalkylation of neutral N-nucleophiles, do not exist in the isolated state, but they are rather efficiently stabilized
upon solvation. These zwitterions, as well as analogous O-anions generated from anionic N-nucleophiles, can serve as intermediates
of N-acylalkylation, as was demonstrated by localization of the corresponding TS.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1150–1164, June, 2007. 相似文献
4.
V. A. Makarov A. L. Sedov O. S. Anisimova V. G. Granik 《Chemistry of Heterocyclic Compounds》1996,32(6):699-707
Highly polarized enediamines of the a, -diamino--cyano--nitroethylene type have been obtained by the hydrolysis of 4-chloro-5-nitropyrimidines. Several chemical conversions of the enamines obtained have been studied, particularly leading to derivatives of 2-(cyanonitromethylene)imidazoline and -hexahydropyrimidine, and also to derivatives of N, N-bisvinylpiperazine and 7 methylene-1, 4-diazabicyclo(2.2. 1 ]heptane.Center for Drug Chemistry, All-Russian Chemical and Pharmaceutical Research Institute, Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 811–820, June, 1996. Original article submitted February 6, 1996.For Part 1, see [1]. 相似文献
5.
T. S. Safonova M. P. Nemeryuk N. A. Grineva A. F. Keremov O. S. Anisimova N. P. Solov’eva 《Chemistry of Heterocyclic Compounds》2004,40(12):1609-1617
We have studied some properties and conversions of pyrimido[4,5-b]-1,4-benzothiazepines: reduction, oxidation, reactions with nucleophilic reagents (methanol, hydrazine, hydroxylamine, o-methylhydroxylamine, and thiosemicarbazide). We have synthesized derivatives of a novel heterocyclic system: pyrimido[5,4-c]isoquinoline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1863–1872, December, 2004.For Communication 53, see [1]. 相似文献
6.
M. S. Shvartsberg S. F. Vasilevskii T. V. Anisimova V. A. Gerasimov 《Russian Chemical Bulletin》1981,30(6):1071-1076
Conclusions Acetylenyl-N-methylpyrazolecarboxylic acids containing an acetylenic substituent and a carboxyl group on adjacent carbon atoms cyclize in pyridine in the presence of copper phenylacetylenide to pyranopyrazoles. The same compounds are obtained by the acetylenide cyclocondensation of the appropriate iodopyrazolecarboxylic acids, but at a much lower rate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1342–1348, June, 1981. 相似文献
7.
Single crystals of potassium iron hydrogen phosphate, KFe3(HPO4)2(H2PO4)6 · 4 H2O, were prepared hydrothermally by heating a mixture of Fe2O3, H3PO4 and K2CO3 with a small amount of water. It crystallizes monoclinic, space group C2/c (N° 15 Int. Tab.) with Z = 4 and a = 1701(2), b = 960.4(5), c = 1750(1) pm, β = 90.88(7)°. The crystal structure was solved by using 1716 unique reflections F0 > 4σ(F0) with a final wR2 value of 0.126 (SHELXL-93). The main feature of the crystal structure are layers formed by PO4-tetrahedra around the FeO6-octahedra parallel to (001). K+ and H2O molecules connect these layers. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), Charge Distribution (CHARDI) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound. The existence of hydrogen bonds is confirmed by these calculations. 相似文献
8.
D. V. Sokolskii N. V. Anisimova A. K. Zharmagambetova A. Ualikhanova 《Reaction Kinetics and Catalysis Letters》1981,17(3-4):419-421
The effect of hydrogen pressure on the selectivity of hydrogenation of 2-butene-1-al at the carbonyl group in the presence of Ru and Ru–ZnO catalysts indicates that the selectivity on the modified ruthenium catalyst in the pressure range of 0.51–8.08 MPa is a maximum at
.
-2--І Ru Ru–ZnO-. , 0,51–8,08 , .相似文献
9.
L. G. Levkovskaya L. A. Serochkina O. S. Anisimova N. P. Solov'eva Yu. N. Sheinker T. S. Safonova 《Chemistry of Heterocyclic Compounds》1987,23(12):1360-1364
1,2-Dioxo-3a-alkyl-7-chloroimidazolidino[3,2-f]pyrido[2,3-b]-1,4-thiazines react with o- and p-nitroanilines, alkyl and acyl halides, and heterocyclic amines to give C(2)- and N(3)-substituted 3a-alkyl-7-chloroimidazolidino[3,2-f]pyridol[2,3-b]-1,4-thiazines.For Communication 44, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1688–1693, December, 1987. 相似文献
10.
V. A. Fedorchuk E. S. Puchkovskaya L. S. Anisimova G. B. Slepchenko 《Journal of Analytical Chemistry》2005,60(6):518-522
Conditions were selected for the voltammetric determination of streptomycin and azitromycin using electrodes of different types. The interfering effects of cations, anions, and organic substances, food proteins among them, on the analytical signals from antibiotics were estimated. Procedures for determining streptomycin and azitromycin in pharmaceuticals and for determining streptomycin in milk at nano levels were developed.__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 6, 2005, pp. 586–591.Original Russian Text Copyright © 2005 by Fedorchuk, Puchkovskaya, Anisimova, Slepchenko.Presented at the VI All-Russian Conference (with international participation) on Electrochemical Methods of Analysis (EMA-2004, Ufa, May 23–27, 2004). 相似文献