Mpro is a homodimeric cysteine protease. The SARS‐CoV‐1 Mpro consists of three domains: I (residues 8–101), and II (residues 102–184), which are β‐barrel domains that shape the chymotrypsin‐like structure, while domain III (residues 201–306) is made up by α‐helices. 124  The CoV Mpro active site uses a catalytic dyad (Cys145‐His41), in which cysteine acts as the nucleophile in the proteolysis while histidine behaves as general acid‐base. The peptide substrate or inhibitor binds in a cleft between domains I and II. 125