Discovery of Ketone-Based Covalent Inhibitors of Coronavirus 3CL Proteases for the Potential Therapeutic Treatment of COVID-19.
Hoffman RL,Kania RS,Brothers MA,Davies JF,Ferre RA,Gajiwala KS,He M,Hogan RJ,Kozminski K,Li LY,Lockner JW,Lou J,Marra MT,Mitchell LJ,Murray BW,Nieman JA,Noell S,Planken SP,Rowe T,Ryan K,Smith GJ,Solowiej JE,Steppan CM,Taggart B
The novel coronavirus disease COVID-19 that emerged in 2019 is caused by the virus SARS CoV-2 and named for its close genetic similarity to SARS CoV-1 that caused severe acute respiratory syndrome (SARS) in 2002. Both SARS coronavirus genomes encode two overlapping large polyproteins, which are cleaved at specific sites by a 3C-like cysteine protease (3CL) in a post-translational processing step that is critical for coronavirus replication. The 3CL sequences for CoV-1 and CoV-2 viruses are 100% identical in the catalytic domain that carries out protein cleavage. A research effort that focused on the discovery of reversible and irreversible ketone-based inhibitors of SARS CoV-1 3CL employing ligand-protease structures solved by X-ray crystallography led to the identification of 3 and 4. Preclinical experiments reveal 4 (PF-00835231) as a potent inhibitor of CoV-2 3CL with suitable pharmaceutical properties to warrant further development as an intravenous treatment for COVID-19.