New cyclometalated gold (III) complex targeting thioredoxin reductase: exploring as cytotoxic agents and mechanistic insights.

A new cyclometalated Au(III) complex highlighting a naphthoquinone-C^N scaffold with formula (NQ-N^C)AuIII(SAd)Cl, 1, in which NQ-N^C: 2-(5-amino-benzo[h]quinolone)-3-(3-methyl-2-butenyl)-1,4-naphthoquinone, HSAd: 1-adamantanethiol, was synthesized and characterized. The interaction of complex 1 with cysteine (CysH) was experimentally and theoretically studied. Complex 1 was more active against MCF-7 and A549 cancer cell lines and less active in a healthy cell (non-tumorigenic cells, MRC-5) than cisplatin. The DNA binding and inhibition of thioredoxin reductase of complex 1 were studied and compared with the molecular docking results. The generation of reactive oxygen species (ROS) and apoptosis of this new complex were also investigated.