Registration Number
0225U000730,
(0121U114247)
, R & D reports
Title
New approaches for amino acids acylation under catalysis by pyridine N-oxides in heterogeneous media
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Вплив природи органічної фази на вихід і швидкість утворення ацильованих α-амінокислот.
Head
Redko Andriy M., Кандидат хімічних наук
Registration Date
17-01-2025
Organization
Institute of Physical and Organic Chemistry and Coal Chemistry. LM Litvinenko of the National Academy of Sciences of Ukraine
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To investigate new ways for amino acids acylation during catalysis by pyridine N-oxides in two-phase water-organic solvent systems. Determine the dependence of the reaction rate, yields, and composition of acylation reaction products on the structure of the acylating reagent, the basicities of N-oxides, the nature of the organic phase, the ratio of phase volumes, acidity, and ionic strength of the aqueous phase.
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The objects of research are α-amino acids, pyridine N-oxides, amino acid imino derivatives of gossypol. The work aims to investigate the effect of the organic solvent on the kinetics reaction and product yields of the benzoylation and sulfonylation of alanine catalyzed by pyridine-N-oxides in two-phase aqueous-organic systems. The research aims to expand existing ideas about the course of IPTC processes and develop a new method for obtaining N-acyl-α-amino acids. The main advantages of the IPTC method are its ability to carry out reactions in water under mild conditions, which meets the requirements of "green chemistry," and ability to obtain N-acyl-α-amino acids with high yields and speeds while saving expensive and toxic organic solvents. Research methods – RP-HPLC, IR, UV, NMR, MALDI-TOF MS. The effect of the organic solvent on the kinetics and yields of the IPTC benzoylation and sulfonylation of alanine in two-phase aqueous-organic systems catalyzed by pyridine-N-oxides was investigated. Effective rate constants were obtained and the previously proposed scheme of the catalytic process was confirmed. It was established that the rates and yields of the IPTC benzoylation and sulfonylation reactions of alanine increase with increasing polarity of the organic solvent. Ethyl acetate is proposed as an optimal organic solvent due to the product's high yields (≥ 80%), catalytic process rate, and environmental friendliness. The rate of IPTC benzoylation and sulfonylation of alanine in two-phase aqueous-organic systems linearly increases with the increasing basicity of the catalyst and its initial concentration in the aqueous phase. The formation of the ionic intermediate is the rate-determining stage. A number of new imino derivatives of gossypol were synthesized. Their structures were established using IR and NMR spectroscopy methods. MALDI-TOF MS was used for their identification. Its applicability for study of α-amino acid imino derivatives of gossypol was confirmed.
Product Description
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Yefimova Iryna V.
Anishсhenko Viktor M.
Anishсhenko Hanna V.
Dykun Oleksii M.
Korzhenevska Nadiia H.
Kucherenko Volodymyr O.
Kushсh Olha V.
Matviienko Anatolii H.
Opeida Liubov I.
Rybachenko Volodymyr I.
Tamarkina Yuliia V.
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2025-01-17
