Table of Contents
Metal-Based Drugs
Volume 6 (1999), Issue 6, Pages 355-360
http://dx.doi.org/10.1155/MBD.1999.355

Binding of Platinum(II) to Some Biologicaly Important Thiols

University of Kragujevac, Faculty of Science, Department of Chemistry, R. Domanovica 12, P. O. Box 60, Kragujevac YU-34 000, Serbia

Received 20 September 1999; Accepted 1 October 1999

Copyright © 1999 Hindawi Publishing Corporation. 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.

Abstract

The reactions between [Pt(terpy)Cl+ and thiols, such as glutathione, L-cysteine, D-penicillamine and thioglycolic acid have been Studied by conventional UV-VIS spectrophotometry and H NMR spectroscopy. The second-ordero rate constants, K2, are similar for these four thiols, varying between 1.06 x 102 and 6.10 x 103M-1s-1 at 25C° . The activation entropies have large negative values between -100 and -200 J mol-1 which are compatible with an associative A mechanism. However, L-methionine, as thioether ligand, is unreactive under the same experimental conditions. The obtained results have been analyzed in relation to the antitumor activity and toxicity of platinum(II) complexes.