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Information × Registration Number 0223U000040, 0121U114247 , R & D reports Title New approaches for amino acids acylation under catalysis by pyridine N-oxides in heterogeneous media popup.stage_title Head Redko Andriy M., Кандидат хімічних наук Registration Date 01-01-2023 Organization Institute of Physical and Organic Chemistry and Coal Chemistry. LM Litvinenko of the National Academy of Sciences of Ukraine popup.description2 Objects of research: α-amino acids, pyridine N-oxides, α-amino acid imino derivatives of gossypol, nanocomplexes based on halloysite. Objective: study of acylation of α-amino acids catalyzed by pyridine N-oxides in two-phase water-organic solvent systems. Within the current stage: determination of the dependence of the composition of products, yields and rates of acylation reactions on the basicity of catalysts, comparison of the catalytic action of DMAP and a number of pyridine N-oxides. Preparation of α-amino acid imino derivatives of gossypol and their nanocomplexes with halloysite. To study the biological activity of a number of α-amino acid imino derivatives of gossypol using QSAR methods. Methods: IR, UV, PMR spectroscopy, RP-HPLC, general methods of synthetic organic chemistry, QSAR methods. Using alanine as an example, it was found that pyridine N-oxides in two-phase water-organic solvent systems are effective catalysts for acylation of α-amino acids. The effective rate constants for catalytic benzoylation and sulfonylation of alanine and the rate constants for the formation of the ionic intermediate were obtained. Their values increases linearly with an increase in the basicity of the catalysts and its initial concentration in the aqueous phase. The composition of the products in the studied reactions was established. It was found that 4-methyl- or 4-methoxy- pyridine N-oxides are optimal for practical use. Nanocomposites of halloysite and gossypol Schiff bases with glycine and alanine have been obtained. QSAR methods were used to study the biological activity of a number of α-amino acid imino derivatives of gossypol and found that some of them have significantly lower toxicity than the original gossypol and are promising raw materials for the creation of drugs. The presented results can be recommended for developing a new convenient method for the preparation of N-acylated α-amino acids, which are used in medicine, perfumery, food, and other industries. Product Description popup.authors Efimova Irina V. Anishchenko Viktor M. Anishchenko Hanna V. Dykun Oleksiy M. Kompanets Mikhaylо О. Korzhenevska Nadiia Н. Opeida Lubov I Ostapiuk Svitlana M. Rybachenko Volodymyr I. Tamarkina Yuliya V. popup.nrat_date 2023-01-01 Close