Химия

The quenching of fluorescence of europium chelate (111) with tenoiltrif- toratseton solubilized in the micelles of Bridge-35 with rutin is studied. The possibility of a direct fluorimetric determination of bioantioxidants in the drug «Ascorutin» with a detection limit of 2.9 10   M is shown.

Phase equilibria and critical phenomena in cut 3 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 5-90°C. We have determined the temperature dependence of the solution composition corresponding to the critical solution point of the immis- cibility region.

Phase equilibria and critical phenomena in the ternary system potas­ sium formate - water - n.butoxyethanol, where a constituent binary liquid system is characterized by phase separation with a closed delamination region, were studied by means of the visual-polythermal method within 25-170°C. The temperature dependences of the com­ positions of the mixtures corresponding to the critical solubility points in the delamination region were determined.

The bromination of condensed chromen-2-ones is carried out. The influence of medium on the reaction occurrence has been studied. In the acidic acid solution aromatization of the 4H-pyrane fragment or hydrogen atom substitution at the tertiary carbon atom takes place. In chloroform, addi­ tion of bromine by the double bond occurs. Mixture of tetrachloromethane and propanol-2 promotes the intermolecular dehydration with the formation of ether bond.

A technique of laboratory  synthesis  of potassium formate has  been developed. Phase equlibria in mixtures  of the components  of the binary  system potassium formate - water in the range from -70 to +170°C were investigated by  the visual-polythermal method. For the first time the phase diagram of the specified system has  been con­ structed and the coordinates  of an eutectic  point has  been estab­ lished. The formation of a crystalline hydrate КНСООИ.бНгО incon­ gruous  melting at -9.2°C was  found in this  system.

Потенциометрическим методом исследовано комплексообразо­вание редкоземельных  элементов (РЗЭ) La, Се, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm и Yb с о-фталевой кислотой при р = 0.2(KCI) в интервале температур 298-328 К. В области pH = 3.8-5 обна­ружено существование комплексной частицы состава LnL , где

The role of spatial and electronic  structure, hydrophobic  properties and concentration of organoselenium compounds  on their interaction with fungal metabolites  - carbohydrate-binding proteins, extracellular lectins  of Lentinula edodes (shiitake mushroom) has  been consi­ dered. By  the hybrid density  functional theory  method at the B3LYP/6-31G(d,p) theory  level, spatial and electronic  structure of the 1,5-di(4-R-phenyl)-3-selenopentanediones-1,5 molecules  has  been studied.

The bioptates  of 170 patients  with ulcer disease and stomach cancer were analyzed to reveal Helicobacter pylori with the help of histological and molecular-genetic  techniques. The cantomination levels  of Helicobacter pylori in various  clinical cases  were determined. The most virulent strains responsible for complication development, including ulcer-cancer transformations, were revealed.

Substituted quinazolines of various degrees of saturation and functionalization possess a wide spectrum of biological activity, in particular, anticancer activity, which predetermines the importance of obtaining new representatives of this type of compounds and studying their practically useful properties. Methods for the preparation of 2-cyanoiminoquinazolines are poorly described in the literature, while their properties and oxidation reactions have not been studied at all.