Spectroscopic and DNA interaction studies on mixed ligand copper(II) complexes of dicyanamide with ethylenediamine or 1,3-diaminopropane

ABSTRACT

Mixed ligand copper(II) complexes of dicyanamide with different polyamines, viz. ethylenediamine (1) and 1,3-diaminopropane (2), have been synthesized and characterized. The crystal structure of complex 1 contains a five-coordinated copper in a distorted square-pyramidal environment and forms 1D zig-zag polymeric chain via the bridging ligand dicyanamide. Hydrogen bonding contributes supramolecular architecture in the crystal. Electronic spectral studies suggest the distorted square-pyramidal structure of the complexes. The interaction of the copper(II) complexes with calf-thymus DNA reveals nonintercalative binding mode. The two complexes have antimicrobial activity against the bacteria (viz. Salmonella paratyphi), which is responsible for paratyphoid fever.

KEYWORDS:

• Antimicrobial activity
• CT-DNA
• polymeric copper(II) complex
• sodium dicyanamide

Acknowledgments

The authors thank Prof. Ashutosh Ghosh, Department of Chemistry, Calcutta University, for his valuable crystallographic discussions. The authors gratefully acknowledged IIT Bombay, Mumbai, India, for recording EPR spectra.

Funding

S. Pramodini Devi is grateful to DST, Government of India, for financial support under DST-Women Scientist Scheme-A.