Ferrocene-Promoted Photoactivated DNA Cleavage and Anticancer Activity of Terpyridyl Copper(II) Phenanthroline Complexes

• DOI: 10.1021/om100524x
• Publication Date: 2010-07-20T19:07:16Z
• Authors: Basudev Maity; Mithun Roy; Bhabatosh Banik; Ritankar Majumdar; Rajan R. Dighe; Akhil R. Chakravarty
• Keywords: Development & Genetics (formed by the merger of DBGL and CRBME); Molecular Reproduction; 540; 01 natural sciences; Inorganic & Physical Chemistry; 0104 chemical sciences

Ferrocene-appended copper(II) complexes [Cu(Fc-tpy)(B)](ClO4)2 (1−3) and [Cu(Ph-tpy)(dppz)](ClO4)2 (4) as control, where Fc-tpy is 4′-ferrocenyl-2,2′:6′,2′′-terpyridine, Ph-tpy is 4′-phenyl-2,2′:6′,2′′-terpyridine, and B is a phenanthroline base, viz., 1,10-phenanthroline (phen, 1), dipyridoquinoxaline (dpq, 2), and dipyridophenazine (dppz, 3), were prepared and structurally characterized, and their DNA binding, photoactivated DNA cleavage activity, and cytotoxic properties were studied [Fc = (η5-C5H4)FeII(η5-C5H5)]. Complexes 1 and 3 as hexafluorophosphate salts were structurally characterized by X-ray crystallography. Molecular structures of [Cu(Fc-tpy)(phen)](PF6)2 (1a) and [Cu(Fc-tpy)(dppz)](PF6)2·MeCN (3a·MeCN) show a distorted square-pyramidal geometry at copper(II), with the Fc-tpy ligand and the phenanthroline base showing respective tridentate and bidentate binding modes. The phenanthroline base exhibits axial−equatorial bonding, while the Fc-tpy ligand binds at the basal plane. The complexes sho...