`ISRN Physical ChemistryVolume 2012 (2012), Article ID 260171, 11 pageshttp://dx.doi.org/10.5402/2012/260171`
Research Article

## A QSPR Study for the Prediction of the pKa of N-Base Ligands and Formation Constant Kc of Bis(2,2′-bipyridine)Platinum(II)-N-Base Adducts Using Quantum Mechanically Derived Descriptors

1Physics Department, Faculty of Sciences and Arts, Harran University, Osmanbey, 63300 Sanliurfa, Turkey
2Chemistry Department, Faculty of Sciences and Arts, Harran University, Osmanbey, 63300 Sanliurfa, Turkey
3Primary Science Education Department, Faculty of Education, Akdeniz University, Dumlupinar Bulvari, 07058 Antalya, Turkey

Received 9 July 2012; Accepted 29 July 2012

Academic Editors: J. G. Han and W. P. Hu

Copyright © 2012 Selami Palaz et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

1. W. J. Lyman, W. F. Reehl, and D. H. Rosenblatt, Handbook of Chemical Property Estimation Methods: Environmental Behavior of Organic Compounds, American Chemical Society, Washington, DC, USA, 1992.
2. E. Demchuk and R. C. Wade, “Improving the continuum dielectric approach to calculating p${K}_{a}$s of ionizable groups in proteins,” Journal of Physical Chemistry, vol. 100, no. 43, pp. 17373–17387, 1996.
3. P. J. Martel, C. M. Soares, A. M. Baptista et al., “Comparative redox and p$Ka$ calculations on cytochrome c3 from several Desulfovibrio species using continuum electrostatic methods,” Journal of Biological Inorganic Chemistry, vol. 4, no. 1, pp. 73–86, 1999.
4. M. Schaefer, M. Sommer, and M. Karplus, “pH-dependence of protein stability: absolute electrostatic free energy differences between conformations,” Journal of Physical Chemistry B, vol. 101, no. 9, pp. 1663–1683, 1997.
5. G. Schüürmann, M. Cossi, V. Barone, and J. Tomasi, “Prediction of the p${K}_{a}$ of carboxylic acids using the ab initio continuum-solvation model PCM-UAHF,” Journal of Physical Chemistry A, vol. 102, no. 33, pp. 6706–6712, 1998.
6. C. O. Silva, E. C. Da Silva, and M. A. C. Nascimento, “Ab initio calculations of absolute p$Ka$ values in aqueous solution II. Aliphatic alcohol, thiols, and halogenated carboxylic acids,” Journal of Physical Chemistry A, vol. 104, no. 11, pp. 2402–2409, 2000.
7. H. Li, A. W. Hains, J. E. Everts, A. D. Robertson, and J. H. Jensen, “The prediction of protein p${K}_{a}$'s using QM/MM: the p${K}_{a}$ of lysine 55 in turkey ovomucoid third domain,” Journal of Physical Chemistry B, vol. 106, no. 13, pp. 3486–3494, 2002.
8. J. E. Davies, N. L. Doltsinis, A. J. Kirby, C. D. Roussev, and M. Sprik, “Estimating p$Ka$ values for pentaoxyphosphoranes,” Journal of the American Chemical Society, vol. 124, no. 23, pp. 6594–6599, 2002.
9. E. Soriano, S. Cerdán, and P. Ballesteros, “Computational determination of p$Ka$ values. A comparison of different theoretical approaches and a novel procedure,” Journal of Molecular Structure, vol. 684, no. 1–3, pp. 121–128, 2004.
10. P. R. Duchowicz and E. A. Castro, “QSPR study of the acidity of carbon acids in aqueous solutions,” Mendeleev Communications, vol. 12, no. 5, pp. 187–189, 2002.
11. J. Ghasemi, S. Saaidpour, and S. D. Brown, “QSPR study for estimation of acidity constants of some aromatic acids derivatives using multiple linear regression (MLR) analysis,” Journal of Molecular Structure, vol. 805, no. 1–3, pp. 27–32, 2007.
12. M. Hennemann and T. Clark, “A QSPR-approach to the estimation of the pKHB of six-membered nitrogen-heterocycles using quantum mechanically derived descriptors,” Journal of Molecular Modeling, vol. 8, no. 4, pp. 95–101, 2002.
13. M. Goodarzi, M. P. Freitas, C. H. Wu, and P. R. Duchowicz, “p${K}_{a}$ modeling and prediction of a series of pH indicators through genetic algorithm-least square support vector regression,” Chemometrics and Intelligent Laboratory Systems, vol. 101, no. 2, pp. 102–109, 2010.
14. M. J. Citra, “Estimating the p${K}_{a}$ of phenols, carboxylic acids and alcohols from semi-empirical quantum chemical methods,” Chemosphere, vol. 38, no. 1, pp. 191–206, 1999.
15. N. Bodor and M. J. Huang, “An extended version of a novel method for the estimation of partition coefficients,” Journal of Pharmaceutical Sciences, vol. 81, no. 3, pp. 272–281, 1992.
16. B. Rosenberg, L. Van Camp, and T. Krigas, “Inhibition of cell division in Escherichia coli by electrolysis products from a platinum electrode,” Nature, vol. 205, no. 4972, pp. 698–699, 1965.
17. G. Momekov and D. Momekova, “Recent developments in antitumor platinum coordination compounds,” Expert Opinion on Therapeutic Patents, vol. 16, no. 10, pp. 1383–1403, 2006.
18. CODESSA PRO (Comprehensive Descriptors for Structural and Statistical Analysis), Semichem, 7204, Mullen, Shawnee, KS, 66216 USA, Copyright, Semichem and the University of Florida, 1995 –2004.
19. Y. Kawanishi, T. Funaki, T. Yatabe et al., “Spectral evidence and DFT calculations on the formation of bis(2,2′-bipyridine)platinum(II)-N-base adducts,” Inorganic Chemistry, vol. 47, no. 9, pp. 3477–3479, 2008.
20. AMPAC 9, 1992 –2008 Semichem, Inc. 12456 W 62nd Terrace—Suite D, Shawnee, KS, 66216 USA.
21. A. Golbraikh and A. Tropsha, “Beware of q2!,” Journal of Molecular Graphics and Modelling, vol. 20, no. 4, pp. 269–276, 2002.
22. E. Clementi, Computational Aspects of Large Chemical Systems, Springer, New York, NY, USA, 1980.
23. M. J. S. Dewar, E. G. Zoebisch, E. F. Healy, and J. J. P. Stewart, “AM1: a new general purpose quantum mechanical molecular model,” Journal of the American Chemical Society, vol. 107, no. 13, pp. 3902–3909, 1985.
24. http://www.codessa-pro.com/manuals/Manual-codessa_pro.doc#_Toc92790360.
25. D. T. Stanton and P. C. Jurs, “Development and use of charged partial surface area structural descriptors in computer-assisted quantitative structure-property relationship studies,” Analytical Chemistry, vol. 62, no. 21, pp. 2323–2329, 1990.
26. D. T. Stanton, L. M. Egolf, P. C. Jurs, and M. G. Hicks, “Computer-assisted prediction of normal boiling points of pyrans and pyrroles,” Journal of Chemical Information and Computer Science, vol. 32, pp. 306–316, 1992.
27. N. S. Zefirov, M. A. Kirpichenok, F. F. Izmailov, and M. I. Trofimov, “Scheme for the calculation of the electronegativities of atoms in a molecule in the framework of Sanderson’s frinciple,” Doklady Akademii Nauk SSSR, vol. 296, pp. 883–887, 1987.
28. M. A. Kirpichenok and N. S. Zefirov, “Electronegativity and molecular geometry I. General basis of the developed approach and determination of the effect of closer electrostatic interactions on bond lengths in organic molecules,” Zhurnal Organicheskoi Khimii, vol. 23, pp. 673–703, 1987.
29. A. Cartier and J. L. Rivail, “Electronic descriptors in quantitative structure-activity relationships,” Chemometrics and Intelligent Laboratory Systems, vol. 1, no. 4, pp. 335–347, 1987.
30. H. Sklenar and J. Jager, “Molecular structure-biological activity relationships on the basis of quantum-chemical calculations,” International Journal of Quantum Chemistry, vol. 16, pp. 467–484, 1979.
31. A. C. Gaudio, A. Korolkovas, and Y. Takahata, “Quantitative structure-activity relationships for 1,4-dihydropyridine calcium channel antagonists (nifedipine analogues): a quantum chemical/classical approach,” Journal of Pharmaceutical Sciences, vol. 83, no. 8, pp. 1110–1115, 1994.