Chemical Transformations of 4-(4-Aminophenyl)-2,6-diphenylpyrimidine

Russian Journal of Organic Chemistry - 4-(4-Aminophenyl)-2,6-diphenylpyrimidine was synthesized by reaction of (E)-1-(4-aminophenyl)-3-phenylprop-2-en-1-one with benzamidine and was involved in a...     

Molecular interactions in a surfactant-water-polyacrylamide system, according to densimetry, viscometry, conductometry, and spectroscopy data

Molecular interactions in a surfactant-polyacrylamide-water system are investigated. It is established that the interactions affect such physicochemical parameters of the system as viscosity, density, surface tension, conductivity, and critical micelle concentration. It is shown that in a polyacrylamide-water system, raising the polyacrylamide concentration to 0.02% causes conformational changes in its macromolecule.     

Synthesis and Some Transformations of 4-Alkoxymethyl-2-ethoxycarbonyl-2-ethoxycarbonylmethylbutanolides

A method was developed for the production of 4-alkoxy-2-ethoxycarbonyl-2-ethoxycarbonylmethylbutanolides. The latter were subjected to alkaline and acid hydrolysis, leading to 4-alkoxymethyl-2-carboxymethylbutanolides, from which lactone-containing thioureas and amides of carboxylactones with novel structures were obtained. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1625–1633, November, 2005.     

Boundary problems with meromorphic symbols in cylindrical domains

We show relative index formulas for boundary value problems in cylindrical domains and Sobolev spaces with different weights at ±∞. The amplitude functions are meromorphic in the axial covariable and take values in the space of boundary value problems on the cross section of the cylinder. Copyright © 2005 John Wiley & Sons, Ltd.     

One-stage synthesis of condensed pyrimidines by reaction of substituted 3-(pyrimidin-5-yl)propanoic acids with <Emphasis Type="Italic">ortho</Emphasis>-diamines: Extension of limits

By condensation of 2-aryl-substituted pyrimidin-5-ylpropanoic acids with 1,2-ethanediamine and 1,2-benzenediamine in polyphosphoric acid new derivatives of heterocyclic systems were synthesized: imidazo- and benzo[4',5']imidazo[1',2':1,6]pyrido[2,3-d]pyrimidines. Unlike that the reaction of substituted 2-mercaptopyrimidin-5-ylpropanoic acid with 1,2-benzenediamine in polyphosphoric acid in the presence of equimolar amount of ZnCl₂ proceeds by a tandem mechanism with the formation of 4-methyl-5,6-dihydrobenzo[4',5']imidazo[1',2':1,6]pyrido[2,3-d]pyrimidine-2-thiol and the corresponding disulfide.     

Asymptotics of the eigenvalues of Sturm-Liouville problem

We prove a new asymptotic formula for the eigenvalues of Sturm-Liouville problem with summable potential. The obtained result extends and make more precise previously known formulas, and takes into account the smooth dependence of the spectral data on boundary conditions.     

Design,antihuman immunodeficiency activity and molecular docking studies of synthesized 2-aryl and 2-pyrimidinyl pyrrolidines

Molecular Diversity - A series of thirty-one new compounds were synthesized and evaluated for their anti-HIV-1 and cytotoxicity activity. Of these, twelve were found to be inhibitors of HIV...     

Electron and hole states in a narrow-band semiconductor InSb film in the presence of uniform electrostatic field

The states of charge carriers in a narrow-gap semiconductor InSb film, placed in a uniform electrostatic field, are considered theoretically. We consider the case when the heavy holes are described by the standard dispersion, and Kane’s dispersion law takes place for electrons and for light holes within the framework of two-band mirror model. For a certain range of values of the external field, explicit expressions for the energy spectrum and the envelope wave functions of charge carriers are obtained. Corresponding numerical estimations of allowed range of the external field are derived, for which the proposed approach allows exact analytical solutions.     

Access to chiral α-bromo and α-H-substituted tertiary allylic alcohols via copper(I) catalyzed 1,2-addition of Grignard reagents to enones

The catalytic asymmetric synthesis of tertiary alcohols by the addition of organometallic reagents to ketones is of central importance in organic chemistry. The resulting quaternary stereocentres are difficult to prepare selectively by other means despite their widespread occurrence in natural products and pharmaceuticals. Here we report on a new methodology which allows access to both α-bromo-substituted and α-H-substituted allylic tertiary alcohols with excellent yields, and enantioselectivities of up to 98% using the copper(I)-catalysed 1,2-addition of Grignard reagents to enones. As an example, the methodology is applied in the synthesis of a chiral dihydrofuran.