Organometallic conjugates of artesunate: synthesis and evaluation of anticancer potential

New organometallic Ru(II), Rh(III) and Ir(III) complexes containing artesunate were synthesised to ascertain the anticancer effect of combining artesunate with different platinum group metal centres. The synthetic approach involved the preparation of two ligands, di(2-pyridyl) methyl amine (L1) and the dipyridyl-artesunate hybrid (L2), followed by complexation with the metal dimers to produce six complexes, C1-C6. All complexes were evaluated for their anticancer activity against two breast cancer cell lines, MCF-7 and MDA-MB-231, in which they showed moderate to low activity. The complexes containing the artesunate moiety, C4-C6, showed higher activity. All complexes had low to no cytotoxicity against the normal breast cell line, MCF-12A, showing potential selectivity for cancerous cells over normal cells. A potential mode of action, through reactive oxygen species generation, was evaluated, and all complexes were found to lead to an increase in ROS levels in the MDA-MB-231 cells.