Abstract
Our studies implied the golden compounds may be more effective against COVID 19 as they synergy inhibit SARS COV 2 replication and down regulation inflammation cytokine level. Our crystal structure studies firstly revealed Au (I) ions, derived from auranofin (AF) or gold cluster (GA), covalently bind sulfur atom of Cys145 and Cys156 of Mpro of SARS COV 2. The auranofin or gold cluster well inhibit Mpro activity in vitro. Auranofin or gold cluster could well suppress inflammation cytokine level of IL 6, IL 1β, TNF α via down regulation NF κB activation in macrophage. The cell viability and rat toxicity studies show gold cluster is more safety when compared FDA approved auranofin. The rat pharmacokinetic studies of gold cluster revealed its good bioavailability.