Mono and bimetallic transtion metal complexes that bind DNA

This thesis reports the syntheses and DNA binding properties of a number of novel DNA binding complexes. A library of ruthenium(II) and rhenium(I) complexes incorporating extended terpyridine type ligands has been synthesised (1). The library consists of a series of structurally related complexes in which we have varied the number of hydrogen bonding sites, charge, chirality and steric demand on the complexes. Experimental data offers clear evidence that these complexes interact with DNA, possibly in an intercalative mode, and that varying the characteristics above has significant effects on the nature of the interaction with DNA. Furthermore a series of achiral mono (2) and bimetallic complexes of ruthenium(II) (3) and rhenium(I) (4) incorporating the well-characterised intercalating domain dppz have been assembled. The novel achiral ruthenium system shows good affinity for CT-DNA and there is a 13-fold increase in binding affinity for the di-cationic complex over the mono-cationic complex. The binding of the di-rhenium and bis-ruthenium complexes show increased affinity for CT-DNA however bis-intercalation is not seen and the major contribution to the interaction comes from electrostatic and groove binding interactions.