Synthesis and evaluation of gold(III) complexes as efficient DNA binders and cytotoxic agents

In recent years, great interest has been focused on gold(III) complexes as cytotoxic and antitumor drugs. Recent studies demonstrated that simple bidentate or polydentate ligands containing nitrogen donor atoms may offer sufficient redox stabilization to produce viable Au(III) anticancer drug targets under physiologic conditions. So, we have synthesized square planer Au(III) complexes of type [Au(A(n))Cl-x]center dot Cl-y and characterized them using UV-Vis absorption, C, H, N elemental analysis, FT-IR, LC-MS, H-1 and C-13 NMR spectroscopy. These compounds manifested significant cytotoxic properties in vitro for brine shrimp lethality bioassay. The metal complexes were screened for series of DNA binding activity using UV-Vis absorption titration, hydrodynamic measurement and thermal DNA denaturation study. The nucleolytic activity was performed on plasmid pUC19 DNA. The Michaelis-Menten kinetic studies were performed to evaluate rate of enhancement in metal complexes mediated DNA cleavage over the non-catalyzed DNA cleavage. (C) 2013 Elsevier B.V. All rights reserved.