Exploring Halogen Bonds in 5‑Hydroxytryptamine 2B Receptor–Ligand Interactions

Here, we predicted the potential halogen bonding interaction between compound 2 and the 5-hydroxytryptamine 2B (5-HT2B) receptor and systematically assessed this interaction via structure–activity relationship analysis and molecular dynamics simulations. A physics-based computational protocol was then developed to further explore the opportunity of “designing in” halogen bonding interactions in structure-based ligand design for the 5-HT2B receptor, which not only facilitated the identification of previously uncharacterized halogen bonds in known 5-HT2B ligands but also enabled the rational design of halogen bonding interactions for the optimization of 5-HT2B ligands. As a proof-of-concept, a series of halogen-substituted analogues of doxepin was synthesized and evaluated, which showed improved in vitro and in vivo potency.