Hydrogen bonding and anticancer properties of water-soluble chiral p-cymene Ru(II) compounds with amino-oxime ligands.

The investigation of the hydrogen-bonding effect on the aggregation tendency of ruthenium compounds [(η(6)-p-cymene)Ru(κNHR,κNOH)Cl]Cl (R = Ph (1a), Bn (1b)) and [(η(6)-p-cymene)Ru(κ(2)NH(2-pic),κNOH)][PF6]2 (1c), [(η(6)-p-cymene)Ru(κNHBn,κNO)Cl] (2b) and [(η(6)-p-cymene)Ru(κNBn,κ(2)NO)] (3b), has been performed by means of concentration dependence (1)H NMR chemical shifts and DOSY experiments. The synthesis and full characterization of new compounds 1c, [(η(6)-p-cymene)Ru(κNPh,κ(2)NO)] (3a) and 3b are also reported. The effect of the water soluble ruthenium complexes 1a-1c on cytotoxicity, cell adhesion and cell migration of the androgen-independent prostate cancer PC3 cells have been assessed by MTT, adhesion to type-I-collagen and recovery of monolayer wounds assays, respectively. Interactions of 1a-1c with DNA and human serum albumin have also been studied. Altogether, the properties reported herein suggest that ruthenium compounds 1a-1c have considerable potential as anticancer agents against advanced prostate cancer.