The in vitro cytotoxicities of a number of
gold(I),
silver(I) and
copper(I) complexes containing chiral tertiary
phosphine ligands have been examined against the mouse tumour cell lines P815
mastocytoma,
B16 melanoma [
gold(I) and
silver(I) compounds] and P388 leukaemia [
gold(I) complexes only] with many of the complexes having IC(50) values comparable to that of the reference compounds
cis-diamminedichloroplatinum(ll),
cisplatin, and bis[1,2-
bis(diphenylphosphino) ethane]
gold(I)
iodide. The chiral tertiary
phosphine ligands used in this study include (R)-(2-aminophenyl)methylphenylphosphine; (R,R)-, (S,S)- and (R(*),R(*))-1,2-phenylenebis(methylphenylphosphine); and (R,R)-, (S,S)- and (R(*),R(*))-bis{(2-diphenylphosphinoethyl)phenylphosphino}
ethane. The in vitro cytotoxicities of
gold(I) and
silver(I) complexes containing the optically active forms of the tetra(tertiary
phosphine) have also been examined against the human ovarian
carcinoma cell lines 41M and CH1, and the
cisplatin resistant 41McisR, CH1cisR and SKOV-3 tumour models. IC(50) values in the range 0.01 - 0.04 muM were determined for the most active
compounds, silver(I) complexes of the tetra(tertiary
phosphine). Furthermore, the chirality of the
ligand appeared to have little effect on the overall activity of the complexes: similar IC(50) data were obtained for complexes of a particular
metal ion with each of the stereoisomeric forms of a specific
ligand.