Graphical abstract
The new four η6-arene capped ruthenium(II) complexes 1–4, have been synthesized from the dinuclear precursors [(η6-arene)RuCl2]2 (arene = para-cymeme or benzene) and the corresponding (carboxyphenyl)bis(pyrazolyl)methane ligands, L1 and L2. These complexes 1–4 were studied for DNA binding, DNA cleavage, topo IIα inhibition and cytotoxicity.