Antileukemic activity and cellular effects of rhodium(III) crown thiaether complexes.

The cytostatic properties of novel rhodium(III) thiacrown ether complexes [RhCl(LL)([9]aneS(3))](n+) with either aromatic κ(2)N ligands (n = 2) or anionic chelate ligands (n = 1) have been investigated for the human cancer cell lines HT-29 and MCF-7 and for immortalized HEK-293 cells. Taken together with literature IC(50) values for analogous complexes with polypyridyl ligands or 1,4-dithiane, the in vitro assays indicate that dicationic complexes with soft κ(2)N (imino) or κ(2)S (thiaether) ligands exhibit significantly higher antiproliferative effects than those with hard κ(2)N (amino) ligands. Dicationic complexes are more active than monocationic complexes with similar ligands.

Cell-selective, apoptosis-inducing rhodium(III) crown thiaether complexes.

Half-sandwich rhodium(III) polypyridyl (pp) complexes with the metal atom capped by the facial crown thiaether 1,4,7-trithiacyclononane [9]aneS(3) represent a promising class of apoptosis-inducing potent cytostatic agents. The necrotic damage caused by the complexes is negligible. In vitro cytotoxicity assays with the human cancer cell lines MCF-7 and HT-29 and immortalized HEK-293 cells indicate that the dicationic kappa(2)N(imino) complexes [([9]aneS(3))RhCl(pp)](2+) are much more active than monocationic complexes [([9]aneS(3))RhCl(2)(L)](+) (L=imidazole, CH(3)CN).

Structure-activity relationships and DNA binding properties of apoptosis inducing cytotoxic rhodium(III) polypyridyl complexes containing the cyclic thioether [9]aneS(3).

The Rh(III) polypyridyl complexes of the type [RhCl(pp)([9]aneS(3))](2+) [(pp)=2,2'-bipyridine (bpy), 2,2'-bipyrimidine (bpm),1,10-phenanthroline (phen), pyrazino[2,3-f]quinoxaline (tap), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq), dipyrido[2,3-a:2',3'-c]phenazine (dppz)] 2-7 have been prepared in a stepwise manner by treatment of RhCl(3).3H(2)O with the appropriate polypyridyl ligand (pp) followed by 1,4,7-trithiacyclononane. Interactions of the polypyridyl complexes with DNA were investigated by CD and UV/visible spectroscopy and by gel electrophoresis.