Synthesis, characterization, bioactivities of copper complexes with N-allyl di(picolyl)amine

Four copper(II) complexes with N-allyl di(picolyl)amine were synthesized and characterized by physico-chemical and spectroscopic methods. The spectrophotometric and fluorescence titration data indicate that the [(Aldpa)Cu(L)](ClO4)2 (L = dppz, dione, phen) with conjugated aromatic rings as coordinated ligands can be inserted into the base stacks of DNA more deeply than the [(Aldpa)CuCl2]. The copper(II) complexes [(Aldpa)Cu(L)](ClO4)2 (L = dppz, dione, phen) can inhibit the proliferation of the four cancer cells (Mcf-7, Eca-109, A549 and HeLa) with IC50 0.5–19.2 μM, which is larger than that (23.2–84.3 μM) of [(Aldpa)CuCl2], suggesting their inhibiting activities on the four cancer cells are correlated with their DNA-binding properties. However, the selectivity of [(Aldpa)CuCl2] to cancer cells is better than that of the other three complexes [(Aldpa)Cu(L)](ClO4)2, which indicates the substituents introduced on the secondary amino nitrogen atom of dpa have great contribution to the antitumor activities of these copper(II) complexes.