The compounds of leucine with copper (II) cations in aqueous solutions
https://doi.org/10.20914/2310-1202-2017-4-175-180
Abstract
The structure of alpha-amino acids offers the possibility of the formation of a large number of forms coordination compounds with cations of metals All forms of amino acids can participate in complexation reactions with metal cations: protonated form with metal ions adducts by coordinating with unshared electron pairs of oxygen atoms of carboxyl groups, the stability constants of such complexes are small and they usually like solvate complexes; bipolar and deprotonated forms not only adducts, but also chelation. The study of equilibrium in the system of amino acid - metal cation are most often carried out potentiometric and spectrophotometric methods, allowing fast, with good reproducibility to determine the equilibrium concentration and composition of the solution without displacement of the chemical equilibrium. In the literature, a chelate compound of leucine with copper (II) cations, formed in an alkaline medium with stability constants of 7.89 and 6.45, has been studied in sufficient detail. This paper presents a study of the conditions of complex formation in neutral aqueous solutions in the system containing aliphatic amino acid L, D-leucine and copper cations (II). The difference in the wavelengths corresponding to the maximum optical density indicates a change in the composition of the aqueous solution and the presence of copper leucinate compounds. The existence of a complex compound between bipolar leucine ions and copper (II) cations in neutral aqueous solutions of the composition (СuLеu4)2+ was proved by the spectrophotometric method of isomolar series. For the determination of stability constants using the method of J. Bjerrum with the following assumptions: an amino acid was regarded as monobasic weak acid, the stability constant of complex compounds was calculated as the average of all functional groups of leucine. Defined in the work a measure of stability constants protonated compounds composition (СuLеu4)2+ is equal to 4.27.
About the Authors
L. P. Bondareva
Voronezh state university of engineering technologies
Cand. Sci. (Chem.), associate professor, physical and analytical chemistry department, Revolution Av., 19 Voronezh, 394036, Russia
Cand. Sci. (Chem.), associate professor, physical and analytical chemistry department, Revolution Av., 19 Voronezh, 394036, Russia
E. V. Rusina
Voronezh state university of engineering technologies
student, physical and analytical chemistry department, Revolution Av., 19 Voronezh, 394036, Russia
student, physical and analytical chemistry department, Revolution Av., 19 Voronezh, 394036, Russia
D. V. Ovsyannikova
Voronezh state university of engineering technologies
Cand. Sci. (Chem.), engineer-ecologist, physical and analytical chemistry department, Revolution Av., 19 Voronezh, 394036, Russia
Cand. Sci. (Chem.), engineer-ecologist, physical and analytical chemistry department, Revolution Av., 19 Voronezh, 394036, Russia
References
1. Skopenko V.V., Tsivadze A. Yu., Savranskii A.I. Koordinatsionnaya khimiya [Coordinating chemistry] Moscow, IКТs "Akademkniga", 2009. 325 p. (in Russian)
2. Sigel H. Metal ions in biological systems. Vol. 2. N.Y.; London: Marcel Dekker, 2014. 360 р.
3. Panyushkin V.T., Bukov N.N., Bolotin S.N. Koordinatsionnaya khimiya prirpodnkh aminokislot [Coordination chemistry of natural amino acids] Moscow, Nauka, 2007. 247 p. (in Russian)
4. S?vag?, I. Critical survey of the stability constants of complexes of aliphatic amino acids. Pure and Applied Chemistry. 2015. vol. 65. no. 5. pp. 1029–1080
5. Chidambarm M.V., Bhattacharya P.K. Studies on mixed amino acid and metal chelate. Acta Chimica. 2012. vol. 75. no. 2. pp.123-128.
6. Reddy G. Sotyanarayana S. Formation of the complex of some djyvalent metal ions // Indian J. Chem, 2010. V.28. No 4. pp.337-339.
7. Li N.C. Study of ternary complexes of Cu (II) involving aliphatic carboxylic acids and amino acids. J. Am. Chem. Soc. 2005. vol. 77. pp. 5225-5229
8. Panyushkin V.T., Neudachina L.K. Fiziko-khimicheskie osnovy primeneniya koordinatsionnykh soedinenii [Physico-chemical basis for the application of coordination compounds] Ekaterinburg, Izd. Ural. Univ., 2014. 124 p. (in Russian)
9. Bondareva L. P, Selemenev V.F. Kompleksoobrazovanie fosfoorganicheskikh biologicheski aktivnykh soedinenii [Complexation of organophosphorus biologically active compounds] Voronezh, Nauchnaya kniga, 2012. 232 p.
10. Yatsimirsky K.B., Kriss E.E. Konstanty ustoichivosti kompleksov [Stability contenders of metal complexes with bioligands] Kiev, Naukova Dumka, 1979. pp. 31-57. (in Russian)
11. Grigorova E.V., Bondareva LP, Kornienko Т.S. Equilibrium of methionine in aqueous solutions. Zhurnal obshchei khimi [Journal of general chemistry] 2010. vol. 80. no. 12. pp. 1988-1992. (in Russian)
12. Berthon G. The Stability Constans of Metal Complexes of Amino Acids with Polar Side Chains. Pure & App. Chem. 1995. vol. 67. no. 7. pp. 1117–1240.
Review
For citations:
Bondareva L.P., Rusina E.V., Ovsyannikova D.V. The compounds of leucine with copper (II) cations in aqueous solutions. Proceedings of the Voronezh State University of Engineering Technologies. 2017;79(4):175-180. (In Russ.) https://doi.org/10.20914/2310-1202-2017-4-175-180
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