Optimization of the technology for obtaining ecdysterone from Serratula coronata L. by varying the extraction methods and growth phases A complex study of the aerial part of Serratula coronata L. cultivated in the collection area of medicinal plants of the IRPH «Phytochemistry» (Karaganda) in different phases of growth and using the most optimal extraction methods has been carried out. The content of the main active component of ecdysterone (20E)has been studied. Investigation of the seasonal dynamics of ecdysterone distribution under conditions of varying extraction methods shows that its maximum accumulation is observed during the vegetative phase, and the optimal method in this phase is extraction with isobutyl alcohol, the extract of which contains 13.86 % of ecdysterone and the maceration method with 96.2 % ethyl alcohol with a 20E content of 12.03 %, respectively. It is shown that the maceration with 96.2 % ethyl alcohol is technologically optimal, which fully complies with the international standards of good manufacturing practice (GMP) under pharmaceutical production conditions and excludes the use of toxic and expensive isobutyl alcohol solvent. It has been found that the content of ecdysterone from the beginning of vegetation to the final phase goes down, which is confirmed by the data of high-performance liquid chromatography (HPLC). It is assumed that there is an outflow of ecdysterone to the root system, and then its redistribution occurs as the plant develops further with a partial discharge into the soil. Based on the data on the quantitative content of the target component by the HPLC method, it is recommended that for the preparation of the ecdysterone substance of many actoprotective phytopreparations and valuable WS, the preparation of the above-ground biomass of Serratula coronata L. should be carried out during the vegetation phase of this taxon.
Investigation of interaction between tert.-butyl diamidophosphites and alkyl halides In this article the interaction of tert.-butyldiamidophosphites with various alkyl halides with a mobile halogen atom, in particular, allyl chloride, benzyl chloride and bromomalonic ester under various conditions was studied. It was established that reactions with benzyl chloride and allyl chloride proceeded according to the classical Arbuzov reaction scheme by quartering the phosphorus atom with the formation of the corresponding benzyl and allyl amidophosphonates as the main reaction products. It was stated that the reaction proceeded ambiguously with the formation of various products mixture. This is due to the structure of the intermediate «quasiphosphonium», which depends on the nature of the solvent: the ionic form predominates in polar solvents, and the pentavalent form predominates in non-polar solvents. In addition it was proved that the direction of the reaction depended on the reaction conditions, namely, the temperature and the solvent nature. It was shown that the reaction with bromomalonic ester proceeded through the initial protonation of the phosphorus atom with the formation of a quasiphosphonium compound, the decomposition of which led to the corresponding tetraethyldiamidophosphorous acid.
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