M pro , the main protease of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is essential for the viral life cycle. Accordingly, several groups have performed in silico screens to identify M pro inhibitors that might be used to treat SARS-CoV-2 infections. We selected more than five hundred compounds from the top-ranking hits of two very large in silico screens for on-demand synthesis. We then examined whether these compounds could bind to M pro and inhibit its protease activity. Two interesting chemotypes were identified, which were further evaluated by characterizing an additional five hundred synthesis on-demand analogues. The compounds of the first chemotype denatured M pro and were considered not useful for further development. The compounds of the second chemotype bound to and enhanced the melting temperature of M pro . The most active compound from this chemotype inhibited M pro in vitro with an IC 50 value of 1 μM and suppressed replication of the SARS-CoV-2 virus in tissue culture cells. Its mode of binding to M pro was determined by X-ray crystallography, revealing that it is a non-covalent inhibitor. We propose that the inhibitors described here could form the basis for medicinal chemistry efforts that could lead to the development of clinically relevant inhibitors.
【저자키워드】 X-ray crystallography, Screening, Small molecules, 【초록키워드】 SARS-CoV-2, coronavirus, protease, in vitro, in silico, inhibitors, Replication, temperature, group, analogues, inhibitor, SARS-CoV-2 infections, binding, Protease activity, acute respiratory syndrome, tissue, Compound, M pro, effort, treat, viral life cycle, FIVE, selected, described, identify, performed, examined, culture cells, clinically, inhibit, evaluated, inhibited, was determined, these compound, suppressed, chemotype, denatured, the SARS-CoV-2 virus, 【제목키워드】 SARS-CoV-2, in silico, inhibitor, M pro,