10.1021/ml4004843
The research aimed to explore how modifying the chemical structure of certain compounds could enhance their binding affinity for 5-HT1A receptors, which are important in the central nervous system and targeted by various drugs. 4-Phenyl-1,2,3,6-tetrahydropyridine (THP) is a key chemical structure that was explored for its potential to enhance binding affinity to 5-HT1A receptors compared to its corresponding 4-phenylpiperazine analogues. The study hypothesized that the higher affinity of THP analogues could be attributed to an electrostatic interaction between the distal phenyl ring of the molecule and a phenylalanine residue (Phe 6.52) in the 5-HT1A receptor binding pocket. This interaction is believed to be stabilized by an edge-to-face CH-p interaction, where the phenyl ring of the THP compound and the phenyl ring of the Phe 6.52 residue are almost coplanar. The results showed that the presence of electron-donating groups, particularly two methyl groups in positions 3 and 5, significantly increased the affinity for 5-HT1A receptors. The study concluded that the THP structure, when appropriately substituted, can enhance the CH-p interaction and improve receptor binding, providing valuable insights for the design of high-affinity 5-HT1A ligands.