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Anikina L.V.,RAS Institute of Technical Chemistry
Bioorganicheskaia khimiia

The immunotropic effect of the 2,3-seco derivatives of allobetulon, betulonic acid, and the methyl ester of betulonic acid were studied. It was found that the highest activity is shown by compounds with an oleanane fragment. The presence of a free C28-carboxyl group enhances the activity of lupeolic 2,3-seco derivatives. A significant contribution to the development of the immune response is introduced by a functional group at the C3 atom in the A ring - the C3-carboxy derivatives intensify the processes of antibody production and alter the number and ratio of leukocyte forms. It is shown that 2,3-seco-1-cyano-19beta,28-epoxy-18alpha-olean-3-oic acid stimulates humoral immunity with a positive influence on hematopoiesis. Source

The effect of the pH of aqueous-ethanol mobile phases on the retention and adsorption thermodynamics of the optical isomers of several α-phenylcarboxylic acids on a chiral stationary phase "Nautilus-E" with a grafted antibiotic, eremomycin, was studied. It was determined that ionic interactions dominated in the retention of α-phenylcarboxylic acid enantiomers. It was revealed that the Nautilus-E adsorbent was most selective to acids, the adsorption of which is an enthalpy-controlled process. It was found that the nature of adsorption was changed by varying the eluent pH. The dissociation constants of α-phenylcarboxylic acids have been determined by chromatographic method in aqueous-ethanol solution. A statistical analysis of the phenomenon of enthalpy-entropy compensation was performed, and a manifestation of the false compensation effect was established. It was shown that the spatial configuration of the molecule and the presence of polar groups on a chiral carbon atom in its structure have a greater influence on the chiral recognition mechanism of acid enantiomers using the Nautilus-E CSP. © 2016 Taylor & Francis. Source

Gorbunova M.,RAS Institute of Technical Chemistry | Lemkina L.,Russian Academy of Sciences
Journal of Nanoparticle Research

New water-soluble nanocomposites based on Ag and copolymers of 2,2-diallyl-1,1,3,3-tetraethylguanidiniumchloride with N-vinylpyrrolidone [poly(AGC-VP)] and vinylacetate [poly(AGC-VA)] have been developed. The average silver particle size ranged from 52 to 62 nm for poly(AGC-VA) and from 28 to 30 nm for poly(AGC-VP), with the corresponding UV-vis absorption peak position at 405-410 nm. The using of copolymers resulted in improvement in bactericide properties of composites. Following these results, the newly developed nanocomposite scaffold may be considered for new water-soluble medicines and biocides. © 2014 Springer Science+Business Media. Source

Lebedev A.V.,RAS Institute of Continuous Media Mechanics | Lysenko S.N.,RAS Institute of Technical Chemistry
Journal of Magnetism and Magnetic Materials

A series of samples of magnetic fluids stabilized with low-molecular weight polypropylene glycol (PPG) of different molecular masses were synthesized. The use of PPG allowed the maximum extension of the carrier fluid range to include ethyl- and butyl-acetate, ethanol, butanol, acetone, carbon tetrachloride, toluene, kerosene and PPG itself. Magnetic and rheological properties of the samples were investigated. Based on the results of investigation it has been concluded that magnetic nanoparticles are covered by a monolayer of surfactant molecules. At low temperatures the propanol-based sample preserves fluidity up to -115 °C. Measurement of critical temperatures of other base fluids showed that alcohols are the best carrier medium. Coagulation stability of the ethanol-based ferrocolloid with respect to water and kerosene was explored. It has been found that kerosene, whose fraction by weight exceeds 22.5%, does not mix with the colloid. This effect can be used to produce magneto-controllable extractors of ethyl alcohol. Under the action of water the colloid coagulates, which allows one to substitute the carrier fluid and to separate the colloid into fractions. © 2010 Elsevier B.V. All rights reserved. Source

Gorbunova M.N.,RAS Institute of Technical Chemistry
Russian Journal of Applied Chemistry

New polymeric guanidinium and phosphonium salts derived from amino acids and polysulfones were prepared. © 2011 Pleiades Publishing, Ltd. Source

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