Crystal structures, antioxidation and DNA binding properties of Dy(III) complexes with Schiff-base ligands derived from 8-hydroxyquinoline-2-carboxaldehyde and four aroylhydrazines.

X-ray crystal and other structural analyses indicate that Dy(III) and every ligand can form a binuclear Dy(III) complex with nine-coordination and 1:1 metal-to-ligand stoichiometry at the Dy(III) center. All the ligands and Dy(III) complexes can bind to Calf thymus DNA through intercalations with the binding constants at the order of magnitude 10(5)-10(7) M(-1), but Dy(III) complexes present stronger affinities to DNA than ligands. All the ligands and Dy(III) complexes can be used as potential anticancer drugs. All the ligands and Dy(III) complexes have strong scavenging effects for hydroxyl radicals and superoxide radicals but complex containing active phenolic hydroxyl group shows stronger scavenging effects for hydroxyl radicals and complex containing N-heteroaromatic substituent shows stronger scavenging effects for superoxide radicals.