Tethering (Arene)Ru(II) Acylpyrazolones Decorated with Long Aliphatic Chains to Polystyrene Surfaces Provides Potent...

The acylpyrazolone proligands HQ^R (HQ^R in general, in detail: HQ^Cy = 1-phenyl-3-methyl-4-carbonylcyclohexyl-5-pyrazolone, 4-C(O)-phenyl, HQ^Ph = 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone, HQ^C17 = 1-phenyl-3-methyl-4-stearoyl-5-pyrazolone, HQ^C17,Ph = 1-phenyl-3-stearyl-4-benzoyl-5-pyrazolone) were synthesized and reacted with (arene)Ru(II) acceptors affording complexes [(arene)Ru(Q^R)Cl] (arene = cymene (cym) or hexamethylbenzene (hmb)). The complexes were characterized by elemental analyses, thermogravimetric analysis-Differntial Thermal Analysis (TGA-DTA), IR spectroscopy, ESI-MS and ¹H, and ¹³C NMR spectroscopy. Complexes [(arene)Ru(Q^R)Cl] where Q^R = Q^C17 and Q^C17,Ph, due to the long aliphatic chain in the ligand, afford nanometric dispersions in methanol via self-assembly into micellar aggregates of dimensions 50-200 nm. The antibacterial activity of the complexes was established against Escherichia coli and Staphylococcus aureus, those containing the ligands with a long aliphatic chain being the most effective. The complexes were immobilized on polystyrene by a simple procedure, and the resulting composite materials showed to be very effective against E. coli and S. aureus.