Theoretical investigation of the conformations of the methylamide of N-acetyl-L-phenylalanine

Russian Chemical Bulletin -     

Limit smoothness of the solutions of variational inequalities under convex constraints on the boundary of the domain

Variational inequalities, connected with quasilinear elliptic systems with a diagonal principal part and a quadratic growth along the gradient, are considered. On the boundary of the domain convex constraints are imposed on the solution. The Hölder continuity of the solution up to the boundary of the domain is proved.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 163, pp. 5–16, 1987.     

Decyl(Tri-Tert-Butyl)Phosphonium Tetrafluoroborate/Palladium Acetate: An Effective Catalyst for Cross-Coupling Reaction of Arylbromides with Phenylacetylene in Copper-Free Conditions

Abstract

The phosphonium salts with sterically hindered cation and noncoordinating anion can be used as phase-transfer reagent in the Sonogashira cross-coupling reaction allowing copper- and amine-free protocol. The reactions proceed under mild conditions with good yields.     

Transition Processes in Solid-Phase Electrochemical Systems Including Sulfur-Containing Components

Transition processes in direct-contact systems Li/Sb₂S₃ and Li/Sb₂S₅ are studied. As shown by potentiodynamic voltammetry, an Li₃SbS₃ interphase is the most probable product of the cathodic reduction at direct-contact interfaces. At certain polarizations and current densities, under potentiodynamic and galvanostatic conditions, the main current-producing processes that lead to the formation of the Li₃SbS₃ interphase compete with passivating cathodic reactions which occur via the mechanism of monolayer adsorption and result in the formation of an Li₂S product which blocks grains of the lithium thiostibnite interphase. Effective transfer coefficients of passivating reactions are twice those of the main current-producing cathodic reactions.__________Translated from Elektrokhimiya, Vol. 41, No. 6, 2005, pp. 675–679.Original Russian Text Copyright © 2005 by Arkhipova, Mikhailova, Seryanov.Published on the basis of a contribution delivered at the VII Meeting on Fundamental Problems in Solid-State Ionics (Chernogolovka-2004).     

An investigation of the conformational states of the methylamide of N-acetyl-L-histidine

Summary 1. All the conformational states of the methylamide of N-acetyl-L-histidine have been calculated.2. It has been shown that in the case of the tautomer of the imidazole ring with a hydrogen atom on the atom, form R of the main chain is preferred, and in the tautomer with the proton on and also in the protonated state of the side chain B forms are preferred.3. The conformational equilibrium is displaced in the direction of form I.M. M. Shemyakin Institute of Biochemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 371–378, May–June, 1976.     

Ionic Lithium-Conducting Solid Li2S–Sb2S x Electrolytes

The electroconductivity of lithium-containing solid electrolyte Li₂S–Sb₂S₃is studied. At room temperature it equals (1.5–2.5) × 10^–4 S cm^–1. The activation energy for conduction, determined from the temperature dependence of the electroconductivity, is 0.35–0.43 eV.