Synthesis and structure of a new mononuclear copper(II) complex with 2,2ʹ-bipyridine and picrate: molecular docking, DNA-binding, and <i>in vitro</i> anticancer activity

Abstract

A new mononuclear copper(II) complex identified as [Cu(bpy)2(pic)](pic), where bpy represents 2,2ʹ-bipyridine and pic stands for picrate (pic), has been synthesized and characterized by elemental analysis, molar conductivity, IR and electronic spectral studies, and single-crystal X-ray diffraction. The crystal structure analysis reveals that copper(II) has a distorted square-pyramidal coordination geometry. The hydrogen bonding and π–π stacking interactions contribute to a 3-D supramolecular structure in the crystal. The DNA-binding properties of the copper(II) complex are investigated both theoretically and experimentally, revealing that the copper(II) complex interacts with herring sperm DNA (HS-DNA) by intercalation, and the molecular docking of the copper(II) complex with the self-complementary DNA duplex of sequence d(ACCGACGTCGGT)2 facilitates the binding events. The in vitro anticancer activities suggest that the copper(II) complex is active against selected tumor cell lines. The influence of the complexation of pic in the mononuclear copper(II) complexes on DNA-binding properties and in vitro anticancer activities is discussed.