Alkyl chain length effect on construction of copper(II) complexes with tridentate Schiff base ligand and DNA interaction

The reaction of the Schiff base ligands with Cu(CH 3 COO) 2 in methanol leads to (CuL 1 ) 4 , 1 and (CuL 2 ) 2 , 2 . In the tetranuclear cubane species, the tridentate H 2 L has both a chelating and a bridging mode, after double deprotonation of the enolic OH groups.

The copper(II) centers are five-coordinate with a NO 4 donor set from the ligands. The coordination geometry around each copper ion is essentially square pyramidal with one nitrogen and two oxygens from one ligand and two oxygens of adjacent ligands from the next unit of the cubane. In dinuclear 2 , H 2 L 2 has chelating and bridging modes after double deprotonation of the enolic OH groups.