Steroid-AuI -NHC Complexes: Synthesis and Antibacterial Activity.

A series of gold(I) pioneer complexes bearing N-heterocyclic carbenes and steroid derivatives (ethynylestradiol and ethisterone) with the generic formula [Au(R2 -imidazol-2-ylidene)(steroid)] (where R=CH3 or CH2 CH2 OCH3 ) were synthesized, and the X-ray structure of a rare of gold(I)-estradiol derivative is discussed. Toxicity studies reveal notable antibacterial activity of the gold-based compounds, which is significantly increased in vivo by the presence of the estradiol unit. Toxicity profiling was estimated in vitro versus Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, and in vivo on Galleria mellonella larvae against E. coli.