Photocytotoxic Copper(II) Complexes with Schiff-Base Scaffolds for Photodynamic Therapy.

Photodynamic therapy (PDT) is a promising and minimally invasive method for the treatment of superficial diseases, and photosensitizers with high phototoxicity indices (defined as (IC )/(IC )) are essential for the development of ideal photosensitizing properties for this technology. Herein, we report a series of photocytotoxic copper(II) complexes [Cu( QYMP)(dppn)] ( QYMP=N,N,O-tridentate Schiff-base derivatives, dppn=benzo[i]dipyrido[3,2-a;2',3'-c]phenazine), the structures of which have been confirmed by mass spectrometry and FTIR spectroscopy. X-ray crystallography revealed that the CuN O core of the [Cu( QYMP)(dppn)](ClO ) complex (3) has a distorted square-pyramidal geometry.