Figure 4.

The binding mode of Compounds 2, 3, 4, 5, and 6 at the active site (amino acid residue SER280 in the Corey-Pauling-Koltun model, other amino acid residues in the line model and ligands in the stick model, among which Compound 2 is expressed in yellow; the receptor surface colored by the interpolated atomic charge—blue represents a positive value and red represents a negative value; the R1-position on ring A highlighted in a blue rectangle).