Fig. (5).

Model of chiral compound docking to FPR2. Geometry of the hydrophobic field surface of the pharmacophore model matches to the binding site geometry of FPR2. An FPR2 agonist can approach the FPR2 binding site from the top (“mouth”) of the cavity, shown by dashed yellow line around the agonist template (hydrophobic regions H₂ and H₃) and around the cavity mouth, which includes subpockets II and III. Field points are colored as follows: blue, electron-rich (negative): red, electron-deficient (positive): yellow, van der Waals attractive (steric). Hydrophobic region H₁ (usually associated with 4-nitrophenyl or 4-bromophenyl groups in FPR2 agonists) should properly fit into subpocket I of the FPR2 ligand-binding site. The cavity of the FPR2 binding site shows the position of side chain tails of compound 53 in subpockets II and III. Surface coloring was made according to electrostatic properties, whereby negatively and positively charged areas are shown in red and blue, respectively. It should be noted, that blue (positively charged) surface areas of the receptor correspond to blue field points obtained with positive probe atom and red (negatively charged) surface areas of the receptor correspond to red field points obtained with negative probe atom. Areas of subpockets are indicated with light-blue arrows. Numeration of subpockets and the hydrophobic surface of the FPR2 pharmacophore model are as reported in [80, 105].