SARS-CoV-2 Mpro-IN-4 is a dual Inhibitor of Main Protease ( M Pro ) and Cathepsin L ( CatL ), with IC 50 s of 900 nM and 60 nM respectively. SARS-CoV-2 Mpro-IN-4 has antiviral activity against SARS-CoV2. SARS-CoV-2 Mpro-IN-4 blocks SARS-CoV2 replication in hACE2 expressing A549 cells with IC 50 value of 8.2 nM.