Evolutionary Development and Structural Diversity of Natural Antimicrobial Peptides,Peptidometics, and Cationic Amphiphiles Based on Amino Acids

Russian Journal of General Chemistry - The review article traces the main trends of the synthetic approach to the solution of the problem of overcoming the resistance of pathogenic bacterial...     

Copolymerization of N,N-diallyl-N,N-dimethylammonium chloride with ethylene glycol vinyl ether in aqueous medium

The radical copolymerization of N,N-diallyl-N,N-dimethylammonium chloride (AMAC) (M₁) with ethylene glycol vinyl ether (M₂) in an aqueous medium proceeds at a high rate to afford random copolymers. The reactivity ratios equal to r ₁ = 2.18 and r ₂ = 0.01 indicate that AMAC is a more active comonomer. The overall reaction order in comonomers is 2.4, and the effective activation energy is 97.4 ± 2 kJ/mol. The monomer M₁ enters into copolymerization by both of the double bonds with the formation of pyrrolidinium structures in the chain through the cyclization stage.     

Direct vinylation of glucose derivatives with acetylene

Vinyl ethers, promising chiral carbohydrate synthons, have been synthesized by the addition of glucose acetals (1,2:5,6-di-O-isopropylidene-α-d-glucofuranose, methyl 4,6-O-benzylidene-α-d-glucopyranoside, 1,2-O-cyclohexylidene-α-d-glucofuranose, methyl α-d-glucopyranoside) to acetylene under atmospheric and elevated pressures in an autoclave in the presence of superbase catalytic systems (KOH-DMSO, t-BuOK-DMSO). The complete vinylation of 1,2:5,6-di-O-isopropylidene-α-d-glucofuranose and methyl α-d-glucopyranoside has been realized under elevated pressure of acetylene in the system KOH-THF as well.     

Vinylation of cellulose in superbase catalytic systems: towards new biodegradable polymer materials

Diverse celluloses including non-mercerized and mercerized ones have been successfully vinylated with acetylene in the superbase catalytic systems MOH/DMSO and MOH/THF (M = Na, K) at 85–140 °C. Depending on the reaction conditions, degree of substitution of the hydroxyl groups by highly reactive polymerazable vinyloxy groups ranges 0.11–1.22, the yields of vinylated celluloses (insoluble in water, but soluble in DMSO) being 41–89 %. Vinylated celluloses are easily decomposed under the action of white rot fungi: Phanerochaete chrysosporium, Trametes versicolor and Trametes hirsutus, and can constitute a basis for the preparation of biodegradable polymer materials (due to polymerization or polyaddition at the vinyloxy group).     

Electrophilic and Nucleophilic Addition of Alkanethiols to 2-Vinyloxyethylmethacrylate

Under acid- or base-catalyzed conditions, thiols add regio- and chemos-electively either to vinyloxy or methacrylate group of vinyloxyalkyl-methacrylates to give polyfunctional methacrylates or polyfunctional vinyl ethers, respectively.     

Nanosized Pd(0)-arabinogalactan composites as catalysts in the Sonogashira reaction

Zero-valent palladium nanoparticles stabilized by arabinogalactan polysaccharide matrix were successfully used for the first time as phosphine-free catalyst in the cross-coupling of terminal alkynes with aryl and hetaryl halides.     

Effect of modification of the MF-4SC membranes in the potassium form with acid salts of heteropolyacids on membrane properties and characteristics of dp sensors based on them

Hybrid materials based on perfluorinated sulfo cation-exchange MF-4SC membrane and nanoparticles of cesium hydrogen phosphotungstate and silicotungstate heteropolyanions were obtained. These membranes with a gradual dopant distribution along the length were used to develop potentiometric sensors for determination of amino-containing organic cations in aqueous solutions at pH < 7. A relationship between the membrane transport characteristics and sensing properties was elucidated.     

Addition of secondary phosphines to a vinyl ether of diacetone-d-glucose: a new approach to optically active phosphines and their derivatives

Secondary phosphines react readily with a vinyl ether of diacetone-d-glucose under radical initiation conditions to give, in high yield, anti-Markovnikov adducts, diorganyl{2-[3-O-(1,2:5,6-di-O-isopropylidene)-d-glucofuranosyloxy]ethyl}phosphines, which oxidize almost quantitatively upon reacting with air oxygen or elemental sulfur to form the corresponding optically active phosphine oxides or sulfides.     

Catalysis of Electrophilic Addition of Alcohols to Alkoxyalkenes by Lithium Salts

Russian Journal of General Chemistry -