Novel Gold(I)– and Gold(III)–N-Heterocyclic Carbene Complexes: Synthesis and Evaluation of Their Anticancer Properties

A novel Au(III)–N-heterocyclic carbene organometallic complex supported by two N-heterocyclic carbene (NHC) ligands was synthesized from Au(SMe2)Cl and 1-methyl-2-pyridin-2-yl-2H-imidazo[1,5-a]pyridin-4-ylium hexafluorophosphate via a Ag intermediate. X-ray crystallography revealed the first example of a square planar geometry adopted by a Au(III) species stabilized by two NHCs and two chloride ligands. The aforementioned Au(I)– and Au(III)–NHC complexes were found to be more potent than cisplatin against the HCT 116, HepG2, A549, and MCF7 cell lines.