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Tautomeric and Microscopic Protonation Constants of Alanine and Valine in Different Aqueous Solutions of Methanol and Tetrahydrofuran

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Abstract

The solute–solvent interactions of alanine and valine were investigated potentiometrically in different aqueous solvent mixtures (0–50 % v/v) of methanol (an amphiprotic solvent) and tetrahydrofuran (a dipolar aprotic solvent). The macroscopic and microscopic protonation constants as well as the tautomeric constants were determined and correlated with either a macroscopic parameter such as dielectric constant or a microscopic parameter such as a Kamlet, Abboud, and Taft (KAT) solvatochromic parameter. The obtained results show that the protonation constants of the amino group (in log10 scale) are linearly related to the reciprocal of the dielectric constants of the water–organic solvent mixtures but this is not true for the protonation of the carboxylic acid group of the amino acids in both systems. Finally, the results are discussed in terms of the effect of solvent on the protonation and tautomeric constants.

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References

  1. Nelson, D.L., Michael, M.: In: Principles of Biochemistry, 4th edn. W.H. Freeman, New York (2005)

    Google Scholar 

  2. Lehninger, A.L.: Principles of Biochemistry, 4th edn. W.H Freeman, New York (2005)

    Google Scholar 

  3. Yudkin, M.D., Offord, R.E.: Biochemistry. Houghton Mifflin Co., Oxford (1975)

    Google Scholar 

  4. D’Angelo, J.C., Collette, T.W.: A method for the measurement of site-specific tautomeric and zwitterionic microspecies equilibrium constants. Anal. Chem. 69, 1642–1650 (1997)

    Article  Google Scholar 

  5. Hilal, S.H., Carreira, L.A., Melton, C.M., Baughman, G.L., Karickhoff, S.W.: Estimation of ionization constants of azo dyes and related aromatic amines: environmental implication. J. Phys. Org. Chem. 7, 122–141 (1994)

    Article  CAS  Google Scholar 

  6. Zapala, L., Kalembkiewicz, J., Sitarz-Palczak, E.: Studies on equilibrium anthranilic acid in aqueous solutions and in two-phase systems: aromatic solvent–water. Biophys. Chem. 140, 91–98 (2009)

    Article  CAS  Google Scholar 

  7. Mahali, K., Roy, S., Krishna Dolui, B.: Thermodynamic solvation of a series of homologous α-amino acids in non-aqueous mixture of ethylene-glycol and N,N-dimethyl formamide. J. Biophys. Chem. 2, 185–193 (2011)

    Article  CAS  Google Scholar 

  8. Demirelli, H.: On the role of the solvent and substituent on the protonation equilibria of di-substituted anilines in dioxane–water mixed solvents. J. Solution Chem. 34, 1283–1295 (2005)

    Article  CAS  Google Scholar 

  9. Sigel, H., Griesser, R.: Nucleoside 5′-triphosphates: self-association, acid-base, and metal ion-binding properties in solution. Chem. Soc. Rev. 34, 875–900 (2005)

    Article  CAS  Google Scholar 

  10. Kauski, R., Murray, C.J.: Enzymichromism: determination of the dielectric properties of an enzyme active site. Tetrahedron Lett. 34, 3363–3366 (1993)

    Article  Google Scholar 

  11. Li, Y.K., Kuliopulos, A., Mildvan, A.S., Talaly, P.: Environments and mechanistic roles of the tyrosine residues of DELTA 5-3-ketosteroid isomerase. Biochemistry 32, 1816–1824 (1993)

    Article  CAS  Google Scholar 

  12. Roses, M., Buhvestov, U., Rafols, C., Rived, F., Bosch, E.: Solute–solvent and solvent–solvent interactions in binary solvent mixtures. A quantitative measurement of the enhancement of the water structure in 2-methylpropan-2-ol–water and propan-2-ol–water mixtures by solvatochromic indicators. J. Chem. Soc. Perkin Trans 2, 1341–1348 (1997)

    Article  Google Scholar 

  13. Mancini, P.M.E., Terenzani, A., Adam, C., Vottero, L.R.: Solvent effects on aromatic nucleophilic substitution reactions. Part 7. Determination of the empirical polarity parameter ET(30) for dipolar hydrogen bond acceptor–co-solvent (chloroform or dichloromethane) mixtures. Kinetics of the reactions of halonitrobenzenes with aliphatic amines. J. Phys. Org. Chem. 10, 849–860 (1997)

    Article  CAS  Google Scholar 

  14. Reichardt, C.: Solvents and Solvent Effects in Organic Chemistry, 3rd edn. VCH, New York (2004)

    Google Scholar 

  15. Staszak, Z., Bartecki, A.: Influence of the bulk and donor–acceptor properties of solvent on ligand field spectra. Spectr. Lett. 22, 1193–1201 (1989)

    Article  CAS  Google Scholar 

  16. Pehrsson, L., Ingman, F., Johansson, A.: Acid–base titrations by stepwise additions of equal volumes of titrant with special reference to automatic titrations—1. Theory, discussion of the Gran functions, the Hofstee method and two proposed methods for calculating equivalence volumes. Talanta 23, 769–774 (1976)

    Article  CAS  Google Scholar 

  17. Gameiro, P., Reis, S., Lima, J.F.L.C., de Castro, B.: Calibration of pH glass electrodes by direct strong acid/strong base titrations under dilute conditions. Anal. Chim. Acta 405, 167–172 (2000)

    Article  CAS  Google Scholar 

  18. Gans, P., Sabatini, A., Vacca, A.: Investigation of equilibria in solution. Determination of equilibrium constants with the Hyperquad suite of programs. Talanta 43, 1739–1753 (1996)

    Article  CAS  Google Scholar 

  19. Jimenez, J.A., Martinez, F.: Thermodynamic study of the solubility of acetaminophen in propylene glycol + water cosolvent mixtures. J. Braz. Chem. Soc. 17, 125–134 (2006)

    Article  CAS  Google Scholar 

  20. Jimenez, J.A., Martinez, F.: Thermodynamic magnitudes of mixing and solvation of acetaminophen in ethanol + water cosolvent mixtures. Rev. Acad. Colomb. Cienc. 30, 87–99 (2006)

    Google Scholar 

  21. Faraji, M., Zare, K., Aghaei, H., Farajtabar, A., Asfari, Z., Gharib, F.: Complexation of p-sulphonato-calix[6]arene by glycine, glycyl-glycine, and glycyl-glycyl-glycine in aqueous solution. J. Solution Chem. 41, 2074–2081 (2012)

    Article  CAS  Google Scholar 

  22. Koseoglu, F., Kilic, E., Dogan, A.: Studies on protonation constants and solvation of some α-amino acids in dioxan–water mixtures. Anal. Biochem. 277, 243–246 (2000)

    Article  CAS  Google Scholar 

  23. Dogan, A., Koseoglu, F., Kilic, E.: Studies on macroscopic protonation constants of some α-amino acids in ethanol–water mixtures. Anal. Biochem. 309, 75–78 (2002)

    Article  CAS  Google Scholar 

  24. Dogan, A., Kilic, E.: Potentiometric studies on protonation constants and solvation of some α-amino acid benzyl- and t-butyl-esters in ethanol–water mixtures. Turk. J. Chem. 29, 41–46 (2005)

    CAS  Google Scholar 

  25. Partanen, J.I., Juusola, P.M., Verraes, V.: Re-evaluation of the second thermodynamic dissociation constants of α-alanine, valine, and leucine using potentiometric data measured for aqueous potassium chloride solutions at 298.15 K. Can. J. Chem. 83, 46–52 (2005)

    Article  CAS  Google Scholar 

  26. Izutsu, K.: Electrochemistry in Nonaqueous Solutions. Wiley, Weinheim (2002)

    Book  Google Scholar 

  27. Garrido, G., Koort, E., Rafols, C., Bosch, E., Rodima, T., Leito, I., Roses, M.: Acid-base equilibria in nonpolar media. Absolute pKa scale of bases in tetrahydrofuran. J. Org. Chem. 71, 9062–9067 (2006)

    Article  CAS  Google Scholar 

  28. Jabbari, M., Gharib, F.: Solute-solvent investigation effects on protonation equilibrium of some water-insoluble flavonoids. J. Solution Chem. 40, 561–574 (2011)

    Article  CAS  Google Scholar 

  29. Barbosa, J., Barron, D., Beltran, J.L., Buti, S.: On the role of solvent in acid–base equilibria of diuretics in acetonitrile–water mixed solvents. Talanta 45, 817–827 (1998)

    Article  CAS  Google Scholar 

  30. Barbosa, J., Toro, I., Sanz-Nebot, V.: Acid-base behavior of tripeptides in solvent used in liquid chromatography. Correlation between pK values and solvatochromic parameters of acetonitrile–water mixtures. Anal. Chim. Acta 347, 295–304 (1997)

    Article  CAS  Google Scholar 

  31. Farajtabar, A., Gharib, F.: Spectral analysis of naringenin deprotonation in aqueous ethanol solutions. Chem. Pap 67, 538–545 (2013)

    Article  CAS  Google Scholar 

  32. Taft, R., Abboud, J.L., Kamlet, M., Abraham, M.: Linear salvation energy relations. J. Solution Chem. 14, 153–186 (1985)

    Article  CAS  Google Scholar 

  33. Jaberi, F., Gharib, F., Farajtabar, A.: Solute–solvent interaction effects on protonation and aggregation constants of TTMAPP in different aqueous solutions of methanol. J. Solution Chem. 42, 1559–1571 (2013)

    Article  CAS  Google Scholar 

  34. Gharib, F., Abbaszadeh, M., Pousti, M.: Acid-base properties of adenosine 5′-monophosphate, guanosine 5′-monophosphate, and inosine 5′-monophosphate in aqueous solutions of methanol. Helv. Chim. Acta 96, 1134–1145 (2013)

    Article  CAS  Google Scholar 

  35. Gharib, F., Feizabadi, M., Soltani, L.: Equilibrium studies of thallium(I) complexes with cytidine 5′-monophosphate in different aqueous solutions of methanol. J. Mol. Liq. 182, 64–69 (2013)

    Article  CAS  Google Scholar 

  36. Jabbari, M., Gharib, F.: Solvent dependence on antioxidant activity of some water-insoluble flavonoids and their cerium(IV) complexes. J. Mol. Liq. 168, 36–41 (2012)

    Article  CAS  Google Scholar 

  37. Taft, R.W., Abboud, J.L.M., Kamlet, M.J.: Linear solvation energy relationships. 28. An analysis of Swain’s solvent “acidity” and “basicity” scales. J. Org. Chem. 49, 2001–2005 (1984)

    Article  CAS  Google Scholar 

  38. Kamlet, M.J., Abboud, J.L.M., Abraham, M.H., Taft, R.W.: Linear solvation energy relationships. 23 A comprehensive collection of the solvatochromic parameters, π*, α, and β, and some methods for simplifying the generalized solvatochromic equation. J. Org. Chem. 48, 2877–2887 (1983)

    Article  CAS  Google Scholar 

  39. Buhvestov, U., Rived, F., Rafols, C., Bosch, E., Roses, M.: Solute–solvent and solvent–solvent interactions in binary solvent mixtures. Part 7. Comparison of the enhancement of the water structure in alcohol–water mixtures measured by solvatochromic indicators. J. Phys. Org. Chem. 11, 185–192 (1998)

    Article  CAS  Google Scholar 

  40. Barbosa, J., Barron, D., Buti, S.: Autoprotolysis constants and standardization of pH measurements in tetrahydrofuran–water mixtures. Electroanalysis 11, 627–631 (1999)

    Article  CAS  Google Scholar 

  41. Puranik, S.M., Kumbharkhane, A.C., Mehrota, S.C.: The static permittivity of binary mixtures using an improved Bruggeman model. J. Mol. Liq. 59, 173–177 (1994)

    Article  CAS  Google Scholar 

  42. Billo, E.J.: Excel for Chemists: A Comprehensive Guide. Wiley, Weinheim (2001)

    Book  Google Scholar 

  43. Gharib, F.: Solvent effects on protonation and complexation of penicillamine and thallium(I) in different aqueous solutions of methanol. J. Chem. Eng. Data 55, 1547–1553 (2010)

    Article  CAS  Google Scholar 

  44. Shamel, A., Saghiri, A., Jaberi, F., Farajtabar, A., Mofidi, F., Abedini Khorrami, S., Gharib, F.: Solvent effects on tautomeric and microscopic protonation constants of glycine in different aqueous solutions of methanol and ethanol. J. Solution Chem. 41, 1020–1032 (2012)

    Article  CAS  Google Scholar 

  45. Dogan, A., Kilic, E.: Tautomeric and microscopic protonation equilibria of some α-amino acids. Anal. Biochem. 365, 7–13 (2007)

    Article  CAS  Google Scholar 

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Correspondence to Farrokh Gharib.

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Gharib, F., Nejhad, B.N. & Nouri, N. Tautomeric and Microscopic Protonation Constants of Alanine and Valine in Different Aqueous Solutions of Methanol and Tetrahydrofuran. J Solution Chem 44, 1655–1672 (2015). https://doi.org/10.1007/s10953-015-0369-2

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