Synthesis, structural characterization and cytotoxic activity of two new organoruthenium(II) complexes

Two new p-cymene ruthenium(II) complexes containing as additional ligands N-methylpiperazine ([(eta(6)-p-cymene)RuCl2(CH3NH(CH2)(4)NH)]PF6, complex 1) or vitamin K-3-thiosemicarbazone ([(eta(6)-p-cymene)RuCl2(K(3)tsc)], complex 2) were synthesized starting from [(eta(6)-p-cymene)(2)RuCl2](2) and the corresponding ligand. The complexes were characterized by elemental analysis, IR, electronic absorption and NMR spectroscopy. The X-ray crystal structure determination of complex 1 revealed "piano-stool" geometry. The differences in the cytotoxic activity of the two complexes are discussed in terms of the ligand present.