Abstract
A series of p-cymene ruthenium(II) complexes with imidazol-2-yl phosphines as PN ligands was prepared. Depending on the number of imidazolyl substituents in the ligands Ph3-nP(im)(n) {1-3: n = 1-3, im imidazol-2-yl (a), 1-methylimidazol-2-yl (b)} different coordination modes were observed: kappa P, kappa N-2,N or kappa N-3,N,N. The complexes were tested for their cytotoxicity in different cancer cell lines. Most of the compounds were found to be non-toxic; The compounds (p-cymene)Ru(1a)Cl-2] (4a) shows cytotoxicity towards A2780sens and Hct116 cells in the mM range but not in H4IIE cells. The cytotoxicity is decreased upon introduction of a methyl group as (p-cymene)Ru(1b)Cl-2] (4b) shows only modest toxicities in the cell lines investigated. The kappa P compound (p-cymene)Ru(2a)Cl-2] (5a) shows selective toxicity in H4IIE cells after 72 h whereas the kappa N-2, N compound (p-cymene)Ru(2a) Cl] OTf (5a') showed no toxicity in the cell lines investigated which again. (C) 2012 Elsevier B. V. All rights reserved.
Huber, Wilhelm