Fig. 4.

The docking conformation and 3D interactions of N3 inhibitor inside the active centre of 3CLpro. (A) Docking conformation of 3CLpro and N3 inhibitor revealed the conformation of ligand (Purple) docked into the active site was almost identical to the original ligand (Green), suggesting the reliability of this docking program. (B) 3D interactions of N3 inhibitor inside the binding pocket of 3CLpro revealed binding energy of −8.5 Kcal/mol, 5 H-bonds (yellow dotted line) and 1 salt bridge(purple dotted line). 3CLpro: 3C-like protease. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)