Химия

The influence of a number of factors on the chromatographic properties of statins (atorvastatin, rosuvastatin, simvastatin) in normal-phase and reverse-phase chromatography modes has been studied by the method of the thin-layer chromatography (TLC) in order to select the most effective analytical systems for the total and separate determination of statins in pharmaceuticals. The study has been performed by ascending TLC on commercial plates with polar, weakly polar, and nonpolar phases.

The method presents obtaining hydrosoluble graft copolymer of complicated structure based on сhitosan, acrylamide (AM), sodium 2-acrylamido-2-methylpropane sulfonic (АМPS-Na) in order to obtain fl ocсulant which is resistant to salt of transition metals and heat temperature, and in order to use it as a reagent for oil production processes.

The analysis of the literature data has showed that there is no information on the behavior in 5(4H)-oxazolones with amines under the conditions of a sealed vessel reactor, which makes it possible to obtain heterocyclic systems with diff erent amines.

This work demonstrates the possibility of obtaining new biologically active molecules containing a privileged imidazolone fragment by the Brønsted acid-catalyzed reaction of 1,3-dimethylurea with 1-(2-oxo-2-phenylethylidene)pyrrolo[3,2,1-ij]quinolin-2-ones. The presence of an active oxoylidene system in ones makes it possible to introduce these compounds into cyclization reactions with various binucleophilic agents.

The results of the study of the influence of various surfactants, cyclodextrins, and ions of Europium on the antibiotics separation according to the method of the thin layer chromatography in medical products are presented.

Conditions selective electroforetic`s allocation of lysine from a mix of amino acids and its definition on color by visualization by a ningidrin are found. Products of interaction of lysine with ningidrin in the water environment and on a cellulose matrix are investigated. The example definition on color of a lysine after electroforetic`s branches is resulted.

Effects of studies of phase equilibriums in binary systems perchloromethane - n-geptadecan and ethylene tetrachloride - n-geptadecan for which one performance of dots of nonvariant equilibriums are determined are resulted. Comparison counted on Schroder - Le-Shatele's method and experimentally found compositions of eutectics has demonstrated that deflection under the content polychlorinated derivative hydrocarbon doesn't exceed 2.7 percent. It testifies that the learnt systems are close to the ideal.

The application of independent component analysis algorithms for simultaneous determination of non-ferrous metals and metals of platinum group in their two- and three-component model mixtures was studied. The comparison between different chemometrical algorithms MILCA, SNICA, SIMPLISMA, RADICAL, JADE was made. The MILCA is the most effective algorithm for analysis of studied systems. The qualitative and quantitative analysis of artificial mixtures of systems of different metals was made.

The paper discusses the results of studying the physicochemical properties of a concentrated acetic-acid solution of chitosan with a stabilized agent added (0.05% of the solution weight), which enables a high fiber-forming ability of the polymer to be revealed. The process of fiber formation from chitosan solution under the action of an electric high-intense field was estimated qualitatively and quantitatively. Chitosan fibers with an average diameter of 280 nm have been obtained, their size-distribution function has been plotted.