SARS-CoV-IN-6 (Compound 17) is an inhibitor of SARS-CoV-1 and SARS-CoV-2 RdRp , with an IC 50 value of 7.8 μM against SARS-CoV-2 RdRp. SARS-CoV-IN-6 reduces cytopathic effects in cells infected with SARS-CoV-1 and SARS-CoV-2 replicon-based single-round infectious particles (SRIPs), and inhibits SARS-CoV N protein expression, with EC 50 values of 0.12 µM for SARS-CoV-1 replicon-based SRIPs and 1.47 µM for SARS-CoV-2 replicon-based SRIPs.