Abstract
The thermal effects of solution of L-phenylalanine in aqueous solutions of urea and dimethylformamide (DMF) at 25°C were determined. The solubility of L-phenylalanine in water and aqueous DMF solutions was measured. The standard enthalpies, free energies, and entropies of solution of the amino acid in aqueous solutions of amides were calculated. The parameters of pair and ternary amino acid-amide interactions were determined within the framework of the McMillan-Mayer theory. The amino acid-amide pair interaction is accompanied by a decrease in the Gibbs free energy, controlled by the entropy term with DMF and by the enthalpy term with urea. The interaction of L-phenylalanine with two amide molecules is repulsive, which in the case of DMF leads to an increase in the standard free energies of solution of the amino acid at the amide mole fraction X 2 > 0.05.
Similar content being viewed by others
References
Tanford, C. and De, K.P., J. Biol. Chem., 1961, vol. 236, no. 6, p. 1711.
Nozaki, Y. and Tanford, C., J. Biol. Chem., 1963, vol. 238, no. 12, p. 4074.
Kessler, Yu.M. and Zaitsev, A.L., Sol’vofobnye effekty. Teoriya, eksperiment, praktika (Solvophobic Effects. Theory, Experiment, Practice), Leningrad: Khimiya, 1989.
Ivanov, E.V. and Abrosimov, V.K., Biologicheski aktivnye veshchestva v rastvorakh. Struktura, termodinamika, reaktsionnaya sposobnost’ (Biologically Active Substances in Solutions. Structure, Thermodynamics, Reactivity), Ser.: Problemy khimii rastvorov (Problems of Chemistry of Solutions), Kutepov, A.M., Ed., Moscow: Nauka, 2001, p. 110.
Belousov, V.P. and Panov, M.Yu., Termodinamika vodnykh rastvorov neelektrolitov (Thermodynamics of Aqueous Nonelectrolyte Solutions), Leningrad: Khimiya, 1983.
Kustov, A.V., Emel’yanov, A.A., Syshchenko, A.F., Krest’yaninov, M.A., Zheleznyak, N.I., and Korolev, V.P., Zh. Fiz. Khim., 2006, vol. 80, no. 9, p. 1724.
Abakshin, V.A. and Krasnoperova, A.P., Eksperimental’nye metody khimii rastvorov. Densimetriya, viskozimetriya, konduktometriya i drugie metody (Experimental Methods of Solution Chemistry. Densimetry, Viscometry, Conductometry, and Other Methods), Ser.: Problemy khimii rastvorov (Problems of Solution Chemistry), Kutepov, A.M., Ed., Moscow: Nauka, 1997, p. 256.
Hovorka, S., Dohnal, V., Carrillo-Nava, E., and Costas, M., J. Chem. Thermodyn., 2000, vol. 32, no. 11, p. 1683.
Belousov, V.P. and Morachevskii, A.G., Teploty smesheniya zhidkostei (Heats of Mixing of Liquids), Leningrad: Khimiya, 1970.
Kustov, A.V. and Korolev, V.P., Zh. Fiz. Khim., 2007, vol. 81, no. 2, p. 245.
Abu-Hamdiyyah, M. and Shehabuddin, A., J. Chem. Eng. Data, 1982, vol. 27, no. 1, p. 74.
Morachevskii, A.G., Smirnova, N.A., Balashova, I.M., and Pukinskii, I.B., Termodinamika razbavlennykh rastvorov neelektrolitov (Thermodynamics of Dilute Nonelectrolyte Solutions), Leningrad: Khimiya, 1982.
Kustov, A.V., Bekeneva, A.V., Savel’ev, V.I., and Korolev, V.P., J. Solution Chem., 2002, vol. 31, no. 1, p. 71.
Kustov, A.V., Bekeneva, A.V., Antonova, O.A., and Korolev, V.P., Thermochim. Acta, 2003, vol. 398, no. 1, p. 9.
Kustov, A.V., Smirnova, N.L., and Korolev, V.P., Zh. Strukt. Khim., 2005, vol. 46, no. 5, p. 894.
Mezhevoi, I.N., Cand. Sci. (Chem.) Dissertation, Ivanovo, 2004.
Savage, J.J. and Wood, R.H., J. Solution Chem., 1976, vol. 5, no. 10, p. 733.
Nelander, K., Olofsson, G., Blackburn, G.M., Kent, H.F., and Lilley, T.H., Thermochim. Acta, 1984, vol. 78, nos. 1–2, p. 303.
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © V.P. Korolev, A.V. Kustov, A.V. Bekeneva, 2007, published in Zhurnal Obshchei Khimii, 2007, Vol. 77, No. 7, pp. 1149–1154.
Rights and permissions
About this article
Cite this article
Korolev, V.P., Kustov, A.V. & Bekeneva, A.V. Thermodynamics of interaction of L-α-phenylalanine with urea and dimethylformamide in aqueous solution. Russ J Gen Chem 77, 1232–1237 (2007). https://doi.org/10.1134/S1070363207070159
Received:
Issue Date:
DOI: https://doi.org/10.1134/S1070363207070159