CCF0058981 (CCF981) is a 3-chlorophenyl analogue which is a noncovalent SARS-CoV-2 3CL pro (SC2) inhibitor with an IC 50 of 68 nM. CCF0058981 inhibits SC1 (SARS-CoV-1 3CL pro ) with an IC 50 of 19 nM. CCF0058981 has antiviral efficacy and has the potential for COVID-19 research .
CCF0058981 (CCF981) exhibits cytopathic effect (CPE) inhibition (EC 50 =497 nM) and plaque reduction (EC 50 =558 nM) in vitro viral replication . CCF0058981 has the 50% cytotoxic concentration (CC 50 ) in the CPE antiviral assay of >50 μM . CCF0058981 has a T 1/2 of 21.1 min, a CL lnt of 141 mL/min kg in Human liver microsomes .