A 1 : 2 copper(II)-tripeptide complex for DNA binding and cleavage agent under physiological conditions

Abstract

A 1 : 2 copper-tripeptide complex, [Cu^II(Boc-His-Gly-His-OMe)₂]²⁺, was synthesized and structurally characterized. The absorption band at 577 nm suggests a square-planar geometry around Cu^II. The DNA-binding and DNA-cleavage properties of the Cu^II complex were investigated. The complex binds to calf thymus DNA (CT DNA) in an intercalative fashion and cleaves plasmid pUC-19 DNA hydrolytically at micromolar concentrations under physiological conditions. The intrinsic binding constant (K_b = 1.2×10² M^-1) for the binding of Cu-tripeptide complex with DNA suggests that this complex is suitable for rapid diffusion on the pharmacological time scale.