Gold(I) N-heterocyclic carbene complexes with an ``activable'' ester moiety: Possible biological applications

While N-heterocyclic carbenes (NHC) are ubiquitous ligands in catalysts for organic or industrial synthesis, their potential to form transition metal complexes for medicinal applications has still to be exploited. Within this frame, new Au(I)-NHC compounds have been synthesized and structurally characterized via different methods. The solid state structure of one of these compounds was also established by X-ray crystallography. Of note, three of them bear a pentafluorophenolic ester group as a possible ``activable'' moiety for further functionalization, which allowed tethering an alkyl amine ligand or another Au(I)-phosphine complex featuring a pendant amine function via microwave activation. The obtained compounds have been tested for their antiproliferative effects in human ovarian cancer A2780 cells, and in non-tumorigenic human embryonic kidney HEK-293T cells, showing promising anticancer properties and a certain selectivity towards cancerous cells. (C) 2014 Elsevier B.V. All rights reserved.