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131.
Vakhid A. Mamedov Nataliya A. Zhukova Alsu A. Balandina Sergey V. Kharlamov Tat'yana N. Beschastnova Il'dar Kh. Rizvanov Shamil K. Latypov 《Tetrahedron》2012,68(36):7363-7373
An efficient and versatile one-step method for the synthesis of thiazolo[3,4-a]quinoxalines and related new heterocyclic systems have been developed on the basis of a new strategy for the construction of the pyrazine ring system. The key step of the process involves the cascade annulation of the iminothiazolopyrazine system to benzene in the reaction of 4-hydroxy-3,5-diaryl-2-phenyliminothiazolidines with 1,2-diaminobenzenes. The use of selenium analogues instead of thiazolidine derivatives in this reaction, leads to selenazolo[3,4-a]quinoxalines and the use of aza analogues instead of 1,2-diaminobenzenes gives aza analogues of thiazolo[3,4-a]quinoxalines. 相似文献
132.
In this work, we consider the inverse scattering problem for a class of one dimensional Dirac operators on the semi-infinite interval with the boundary condition depending polynomially on a spectral parameter. The scattering data of the given problem is defined and its properties are examined. The main equation is derived, its solvability is proved and it is shown that the potential is uniquely recovered in terms of the scattering data. A generalization of the Marchenko method is given for a class of Dirac operator. 相似文献
133.
We obtain large time asymptotic expansions of the solution to the Cauchy problem and the first and second boundary value problems for the Sobolev equation in the quadrant. 相似文献
134.
E. I. Markova M. Kh. Mamedov S. R. Rafieva N. F. Dzhanibekov 《Russian Journal of Applied Chemistry》2012,85(2):256-260
Problems associated with synthesis of metal complexes and salts of dithiophosphates containing phosphorus, sulfur, and nitrogen
heteroatoms and a sterically hindered hydroxy group in their molecule are considered. 相似文献
135.
The kinetics of H2S destruction in the radiolysis of CH4–H2S and CH4–H2S–O2 mixtures has been studied. It has been shown that G(–H2S) depends on amounts of hydrogen sulfide and the presence of oxygen in the starting mixture and is within the range of 5–13 mol/100 eV. G(H2) decreases with the increases of O2 content and amounts to the constant value of 2. 相似文献
136.
The asymptotic distributions are exactly solved for linearly independent solutions considering problem of the second order and for the coefficients of asymptotic distribution the recurrent formulas are obtained. Further, using obtained recurrent formulas the necessary and sufficient conditions for almost regularity of spectral problem for the equation of the second order is proved. 相似文献
137.
138.
139.
Yu. M. Rodionov E. M. Slyusarenko I. I. Novoshinsky A. Sh. Mamedov V. F. Tretyakov E. A. Chernishev V. V. Lunin 《Reaction Kinetics and Catalysis Letters》1997,60(2):285-289
New methods for the synthesis of poly(organyloxy)elementoxanes containing Zr, Zr−Y, Al−Ba (Ca, Sr, Ce, Zr) and La−Sr−Co have
been developed. The application of these elementoxanes as oxide precursors in the preparation of catalyst supports, catalytic
coatings and filter catalysts has been studied. 相似文献
140.