Synthesis, characterization and DNA interaction of copper (II) complexes with Schiff base ligands derived from 2-pyridinecarboxaldehyde and polyamines

A series of copper (II) complexes a–d with Schiff bases ligands derived from the condensation reactions between 2-pyridinecarboxaldehyde and different polyamines (ethylenediamine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine) were synthesized and characterized by elemental analysis, FT-IR spectroscopy, HRMS, molar conductance and molecular modeling studies. The interactions of the copper complexes a–d with DNA were investigated by the UV spectra, viscosity measurements and gel electrophoresis under physiological conditions. The experimental results indicated that four complexes could bind to DNA via an intercalative mode and showed a different DNA cleavage activity with the sequence: > c > > b.