Quantum-Chemical Calculations in Studying of the Properties of 1-(carboxy)-1-(N-methylamide)-2-(3',5'-di-tert-butyl)-4-hydroxyphenyl)-propionates sodium and potassium IN Biological Environment

Authors:

Alexander Volod’kin, Gennady Zaikov, Elena Burlakova and Sergey Lomakin

Energies of formation, enthalpies, and entropies of the conformers of 1-(carboxy)-1-(N-methylamide)-2-(3',5'-di-tert-butyl)-4-hydroxyphenyl)-propionic acid and sodium and potassium 1-(carboxy)-1-(N-methylamide)-2-(3',5'-di-tert-butyl)-4-hydroxyphenyl)-propionates are calculated by quantum-chemical methods in the PM6 approximation. A doubling of signals in the 1H NMR spectrum of the first conformer is observed, which merge into singlets when the compound is heated. Changes in the structure of the conformers and donor-acceptor complexes (solvates) occur with the preservation of the metal–ligand coordination bond. Calculations of the characteristics of 1-(carboxy)-1-(N-methylamide)-2-(3',5'-di-tert-butyl)-4-hydroxyphenyl)-propionic acid and sodium and potassium 1-(carboxy)-1-(N-methylamide)-2-(3',5'-di-tert-butyl)-4-hydroxyphenyl)-propionates in the PM6 approximation make it possible to predict structure and properties of the solvated structures. Energies of homolysis of the H–O bond D(OH) are calculated, and a linear dependence of the antioxidant activity on D(OH) for the structures of the studied compounds is demonstrated. The results make it possible to predict the properties of antioxidants in biological environment.

quantum-chemical calculation

MOPAC 2009

conformer

binding energy

nuclear magnetic resonance and infrared spectroscopies

antioxidant

structure.

[1] Fialkov Yu., Zhitomirskii A. and Tarasenko Yu.: Phizicheskaya Khimiya Nevodnykh Rastvorov. Khimiya, Leningrad, 1973.
[2] Knyazev S., Gordeev E. and Chernyshev E.: Izv. Akad. Nauk, Ser. Khim., 2006, 2074.
[3] Berdyshev D., Glazunov V. and Novikov V.: Izv. Akad. Nauk, Ser. Khim., 2007, 400.
[4] Berdyshev D., Glazunov V. and Novikov V.: Izv. Akad. Nauk, Ser. Khim., 2008, 499.
[5] Egorova A., Vener M., Zhukov I. et al.: Izv. Akad. Nauk, Ser. Khim., 2008, 1157.
[6] Stewart J.: J. Mol. Mod., 2007, 13, 1173.
[7] Berezin I.: PhD thesis, Moscow State Univ., Moskwa 1953.
[8] Volod’kin A., Lomakin S., Zaikov G. and Evteeva N.: Izv. Akad. Nauk, Ser. Khim., 2009, 900.
[9] Ershov V., Piotrovskii K., Tupikina N. et al.: Izv. Akad. Nauk SSSR, Ser. Khim., 1976, 1174.
[10] Searles S. and Kebarle P.: Can. J. Chem., 1969, 47, 2619.
[11] Burlakova E., Aleksenko A. and Molochkina E.: [in:] Emanuel N. (Ed.), Bioantiokcidanty v Luchevom Porazhenii i Zlokachestvennom Roste. Nauka, Moskwa 1975.