Table of Contents
Metal-Based Drugs
Volume 5, Issue 4, Pages 225-231

DNA Binding of Some Chiral Metallointercalators Derived From 9,10-Phenanthrenediamine

1School of Chemistry, Macquarie University, 2109, N.S.W., Australia
2School of Science, University of Western Sydney, Nepean, Kingswood 2747, N.S.W., Australia

Received 1 July 1998; Accepted 14 July 1998

Copyright © 1998 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.


A study of the interaction with calf thymus DNA is described of a novel set of chiral ternary complex cations of general form [Ru(N4-tet)(phdi)]2+ (where N4-tet is the chiral linear tetradentate R*R*-picchxn or R*R*-picchxnMe2). Individual equilibrium binding constants (KB) have been determined from spectroscopic titrations employing the hypochromism induced in the visible absorbance of the cations on interaction with the nucleic acid. These demonstrate both stereo- and enantioselectivity in the binding interactions. These KB data, together with induced circular dichroism and DNA thermal denaturation results, are all indicative of selective intercalation of the bidentate components of the cations into the nucleobase stack of the duplex. Supportive evidence for a secondary binding mode for the picchxn complexes is provided by the different mutagenicity profiles obtained for related cations.