2-(Phenylazo)pyridineplatinum(II) Catecholates Showing Photocytotoxicity, Nuclear Uptake, and Glutathione-Triggered Ligand Release

摘要: Platinum(II) complexes Pt(pap)(an-cat)] (1) and Pt(pap)(py-cat)] (2) with 2-(phenylazo)pyridine (pap), 4-2-(anthracen-9-ylmethylene)amino]ethyl]benzene-1,2-diol (H(2)an-cat), 4-2-(pyren-1-ylmethylene)amino]ethyl]benzene-1,2-diol (H2py-cat) were prepared, their photoinduced cytotoxicity was studied. The found to release catecholate ligand in the presence of excess glutathione (GSH), resulting cellular toxicity cancer cells. complex Pt(pap)(cat)] (3) prepared used as a control. Complex 3, which is structurally characterized by X-ray crystallography, has platinum(II) distorted square-planar geometry. are redox-active, showing responses near 0.6 1.0 V versus SCE N,N-dimethylformamide/0.1 M tetrabutylammonium perchlorate corresponding two-step catechol oxidation process at -0.3 -1.3 for reduction pap ligand. 1 showed remarkable light-induced HaCaT (human skin keratinocytes) MCF-7 breast cancer) cells, giving IC50 value similar 5 mu visible light 400-700 nm >40 dark. 2',7'-dichlorofluorescein diacetate (DCFDA) assay generation reactive oxygen species (ROS), seems trigger apoptosis, evident from annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) assay. fluorescence microscopic images significant nuclear localization free ligands. A mechanistic study revealed possible coordinated azo bond GSH, releasing photochemotherapeutic action complexes.