Figure 3.

Noncovalent complex formed between PF‐00835231 and the 3CL protease of SARS‐CoV‐2. a) Binding pose of the inhibitor in the active site of the protease, showing the location of the catalytic dyad and the oxyanion hole. Note that the carbonyl oxygen is accommodated in the oxyanion hole. b) Fraction of hydrogen bond contacts between residues of PF‐00835231 and a peptide substrate ^[3] and those of the protease. A hydrogen bond contact is counted when the donor–acceptor distance is <3.8 Å and the hydrogen bond angle is >120°. c) Pair distribution functions between the Cys145‐Sγ atom and the carbonyl carbon atom of the substrate (in blue) and to the Nϵ atom of His41 (in red).