Synthesis, characterization and in vitro biological studies of titanocene(IV) derivatives containing different carboxylato ligands

Several titanocene(IV) complexes with different carboxylato ligands such as 3-methoxyphenylacetic acid (3-mpa-COOH), 4-methoxyphenylacetic acid (4-mpa-COOH), 1,4-benzodioxane-6-carboxylic acid (bdo-COOH), 2,5-dimethyl-3-furoic acid (dmf-COOH) and 4-(4-morpholinyl)benzoic acid (mbz-COOH) have been synthesized. All the novel titanocene(IV) carboxylate complexes have been characterized by traditional spectroscopic methods, with the molecular structures of [Ti(η5-C5H5)2(OOC-dmf)2] (7) and [Ti(η5-C5H4Me)2(OOC-dmf)2] (8) being determined by single crystal X-ray diffraction studies. Complexes were tested against the tumour cell line A2780 (ovarian cancer) and showed notable cytotoxicity. In addition, a study of the interaction of 7 and 8 with DNA (probably one of the biological target-molecules of the titanocene derivatives) monitored by UV–visible spectroscopy has been carried out.