A circular dichroism study uncovers a two-step interaction of antitumor azolato-bridged dinuclear platinum(II) complexes with calf thymus DNA

Abstract

The interactions of four antitumor azolato-bridged dinuclear platinum(ii) complexes, [{cis-Pt(NH 3) 2 } 2 (μ-OH)(μ- azolato)] 2+, with calf thymus DNA were monitored dose- and time-dependently, by using circular dichroism. Complexes 1-4 reacted with DNA via a two-step interaction that comprised a prompt diffusion-controlled reaction, which induced a B- to C-form transition, and a relatively slow temperature-dependent reaction. © 2012 The Royal Society of Chemistry.