Modifying the structure of dinuclear ruthenium complexes with antitumor activity

In order to modulate the structure of a recently developed series of antitumor-active, dinuclear Ru(II)–arene compounds, complexes 1c–4c were synthesized. The complexes were modified with respect to their pyridinone moieties and the spacer linking the two metal centers. More particularly, the series of dinuclear ruthenium(II) complexes was extended to compounds with longer spacers, i.e. tetradecane and 3,7,10-trioxotridecane, and the pyridinone ring was modified by replacing the methyl group by an ethyl group and by shifting the position of the methyl group. The organometallic ruthenium compounds were obtained from the reaction between [RuCl2(η6-p-isopropyltoluene)]2 and ligands 1b–4b with yields ranging from 41 to 67%. All compounds were characterized by standard methods: MS, 1H and 13C NMR spectroscopy and elemental analysis. Copyright © 2008 John Wiley & Sons, Ltd.