“…We investigated the antiviral activity of the isolated compound against SARS-CoV-2 together with other compounds isolated in our previous study [ 15 ] including four naphthopyrones, namely, flavasperone ( 1 ), rubrofusarin B ( 2 ), aurasperone A ( 3 ), fonsecinone A ( 4 ) and aspernigrin A alkaloid ( 5 ). Several in silico techniques, including molecular docking, molecular dynamics simulations (MDS), and end-state thermodynamics, are widely used as valuable tools for explaining the biological activities and the binding ability of the tested molecules to important therapeutic targets [ 16 , 17 , 18 ]. SARS-CoV-2 has two proteases, the main protease (M pro ), and the papain-like protease (PL pro ), which are essential for processing the viral non-functional proteins, and they are among the most important therapeutic targets used for the treatment of COVID-19 [ 19 , 20 , 21 ].…”