Fig. 4.

Reference ligands chlorprothixene (a) and olanzapine (b) docked into the orthosteric site of the dopamine D₂ receptor homology model. Key interactions of the protonatable nitrogen atom of the ligands with the conserved Asp 3.32 (presented as sticks) are shown as red dashed lines. Other important residues, Trp 6.48, Phe 6.51 and His 6.55 are also shown as sticks. TMs are colored in spectrum mode. Hydrogen atoms are not shown for clarity