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Information × Registration Number 0224U000494, 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 08-01-2024 Organization Institute of Physical and Organic Chemistry and Coal Chemistry. LM Litvinenko of the National Academy of Sciences of Ukraine popup.description2  The objects of research are α-amino acids, pyridine-N-oxides, and amino acid imino derivatives of gossypol. The work aims to investigate the influence of the structure of α-amino acids on the kinetics of acylation and the yields of reaction products catalyzed by pyridine-N-oxides in two-phase water-dichloromethane systems. The research aim is to expand the ideas about the regularities of the course of IPTC and to develop a new method of obtaining N-acylated α-amino acids, that has significant advantages and meets the requirements of "green chemistry". Research methods - RP-HPLC; IR, UV, NMR spectroscopy, methods of quantum chemistry. The effective rate constants of IPTC benzoylation and sulfonylation of some α-amino acids and the rate constants of the formation of the corresponding intermediates were obtained. It was found that the rate of catalytic benzoylation and sulfonylation increases linearly with the increase in the basicity of the catalyst and its initial concentration in the aqueous phase. The structure of α-amino acids slightly affects the rate of the studied reactions and the yields of the corresponding N-acylamides. However, in the case of benzoylation of arginine, the yield of the product decreases due to hydrolysis. The acylation products were established. It was found that 4-methyl- or 4-methoxypyridine-N-oxides are the most effective catalysts. The imino derivatives of gossypol with glycine and cysteine were synthesized. Their structures were determined. The energies of intramolecular hydrogen bonds for synthesized derivatives of gossypol were estimated. It was established that the studied Schiff bases in solutions and solid states exist in the dienamine tautomeric form, and hydrazones in the diimine form. The results can be used both for the development of the theoretical foundations of the IPTC method and for the improvement of existing methods for obtaining N-acyl amides, which are widely used in many fields due to their biological activity. Product Description popup.authors Efimova Irina V. Anishchenko Viktor M. Anishchenko Hanna V. Dykun Oleksii M. Korzhenevska Nadiia Н. Kucherenko Volodymyr O. Kushch Olha V. Matvienko Anatolii G. Opeida Lubov I. Rybachenko Volodymyr I. Tamarkina Yuliya V. Taran Nadiya A. popup.nrat_date 2024-01-08 Close