Химия

Michael's condensation in a line 3-аryimethilen-5-aryl-3H-furan-2-ones containing activated double bond with cyclohexanone, acetylacetone, acetoacetic ester has been researched. Peculiarities of the reaction have been revealed. The structure of the newly synthesized substances has been clarified with the usage of spectral (IR, NMR H¹, C¹³).

In article the new data is cited on reactions of cross-conjugated dienonic derivative of the alicyclic series (C₅, C₆) with hydrazines proceed to form trans-cyclanopyrazolines. The conditions and regiodirection of the reactions are determined by the alicycle's size and the peripheral substituent nature.

Inter- and intramolecular heterocyclisation carbonyl compounds and them thiacarbam derivatives an alicyclic structure depending of activation of nucleophilic centers it is carried out regiodirectly with formation of unknown earlier annelic and spitoycitic compounds thiazolic and thiadiazolic lines, perspective by way of studying biological activity.

 The innovative component of the research and educational process at the Institute of Chemistry, Saratov State University, and establishment of new structural departments are reported.

Sol-gel materials with immobilized triphenylmethane dyes (Pyrocatechol Violet and Bromphenolic Blue) based on sol-gel technique with tetraethoxysilane were produced. Protolytic properties of the immobilized indicators were investigated. It was shown that these sol-gel films could be use as sensitive elements of pH optical sensors with dynamic range from 1 to 8 pH units. 

A generalized scheme of topological transformation of the phase diagrams of ternary delaminating salt – binary solvent systems with salting-out at changing temperature and under constant pressure has been developed for the cases of the binary liquid constituent system being delaminating with an UCST, LCST, or not delaminating over the whole temperature range of its li

The biological activity of chitosan oligomers of various molecular masses was examined on E.coli (АТСС 25922), S.aureus (АТСС 25923), and fungus Candida albicans (АТСС 10231). All the samples under study inhibited the growth of these microorganisms, especially S.aureus. The dependence of the biological activity of chitosan oligomers on their concentration, exposure time, and molecular mass has been established.

The sorption and bactericide properties of chitosan films with various humidity and preparation temperature were studied. Film chitosan samples have been found to possess high transport properties to water and hydrochloric acid vapors and to show bactericide activity. The temperature of film preparation practically does not influence the sorption properties. The swelling degree, sorption rate, and bactericide effect increase with the film’s humidity. Clinical tests of our film samples have shown their high efficiency at burn treatment.

The viscometric properties of diluted solutions of cellulose diacetate in dimethylsulfoxide in a temperature range 25-65°С were studied. The concentration dependence of the reduced specific viscosity is linear. The limiting viscosity [η] value regularly decreases as temperature grows and the viscosity-average molecular weight of the polymer decreases. The Mark – Kuhn – Howink constants have been determined.

Phase equilibria and critical phenomena in cut 1 of the quaternary system water - pyridine - butyric acid - potassium chloride whose constituent ternary liquid system had a closed binodal curve were studied by means of the visual-polythermal method within 5-80°C. The volumes of two monotectic states in the composition tetrahedron have been found to be in contact via critical tie lines with increasing temperature.