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Reaction of primary C55-allylic alcohol moraprenol (WT3C7-9-OH, a polyprenol from mulberry leaves) with triethylamine in the presence of phosphorus oxychloride leads to a quaternary ammonium chloride with a good yield (72%) and high cis-stereoselectivity of the terminal isoprene unit. Cationic polyprenyl derivatives may be useful for transfection and immunological studies
The synthesis of 4-dichloromethylsulfonyl-2-nitrophenylsulfenyl chloride and its transformation into new compounds with promising pesticidal activity is reported. The title compounds were obtained by a three-step synthesis, starting from 4-dichloromethylchlorophenyl sulfone. It was nitrated and then subjected to the SNAr reaction with sodium disulfide to give proper diphenyl disulfide, which was next chlorinated by chlorine. The obtained phenylsulfenyl chloride was transformed into sulfenamide derivatives by reactions with amines.
Приведен синтез линейных регуляторов для задач оптимального управления нестационарными колебаниями, возникающими в режимах пуска/торможения автомобильных кранов. Для обоснования достаточных условий оптимальности решения указанной задачи, сформулированных В.Ф. Кротовым, установлено и решено методом неопределённых коэффициентов уравнение Р. Беллмана.
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The role of sulfation in the processing of mucus glycoprotein in gastric mucosa was investigated. Rat gastric mucosal segments were incubated in MEM at various medium sulfate concentrations in the presence of [³⁵S]Na₂ SO₄ [³H] glucosamine and [³H]proline, with and without chlorate an inhibitor of PAPS formation. The results revealed that the mucin sulfation attained maximum at 300 µM medium sulfate concentration. Introduction of chlorate into the incubation medium, while having no effect on the protein synthesis as evidenced by [³H]proline incorporation, caused at its optimal concentration of 2 mM a 90% decrease in mucin sulfation and a 40% drop in mucin glycosylation. Evaluation of mucin molecular forms distribution indicated the predominance of the high molecular mucin form in the interacellular fraction and the low molecular mucin from in the extracellular fraction. Increase in medium sulfate caused an increase in the high molecular weight mucin form in both fractions, and this effect was inhibited by chlorate. Also, higher medium sulfate concentrations led to a higher degree of sulfation in the high molecular weight mucin form, the effect of which was inhibited by chlorate. The results suggest that the sulfation process is an early event taking place at the stage of mucin subunit assembly and is required for mucin polymer formation. Hence, the disturbances in mucin sulfation process could be determinal to the maintenance of gastric mucus coat integrity.
The aim of the presented study was to evaluate the reductive activity of antioxidants in the presence of carbon manufactured by Radio Frequency Plasma Activated Chemical Vapor Deposition method (RF PACVD). 2,2-diphenyl-1-picrylhydrazyl (DPPH) method was employed to estimate antioxidants reductive potential. Based on the experimental results, the antioxidant activity of carbon colloid was not confirmed. Nevertheless the reductive activity of antioxidants measured in time manner, in the presence of carbon, was significantly elevated comparing to the antioxidants alone. The presented results suggest that the surface of carbon syn-thetized by RF PACVD method suspended in water, creates more friendly reductive environment for antioxidants with hydroxyl groups (ascorbic acid - AA and butylated hydroxyanisole - BHA) then with sulfhydryl groups (glutathione - GSH).
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