Figure 2. Investigation on the binding pattern of 3CLpro and Indinavir. (A) The location of the binding pocket between 3CLpro and Indinavir. (B) The enlarged view of the binding pocket of 3CLpro and Indinavir. (C) The interaction 2D diagram between 3CLpro and Indinavir. The green rectangles represent VDW interaction. The pink rectangles represent charge and H-bond interactions. Here, the H-bond interactions with the main residues are indicated by the green dashed arrow pointing to the electron donor, and the H-bond interactions with the side chain residues are indicated by the blue dashed arrow pointing to the electron donor.