Piquindone

Piquindone (Ro 22-1319) is an atypical antipsychotic with a tricyclic structure that was developed in the 1980s but was never marketed. It acts as a selective D₂ receptor antagonist, though based on its effects profile its selectivity may be considered controversial. Unlike most other D₂ receptor ligands, piquindone displays Na-dependent binding, a property it shares with tropapride, zetidoline, and metoclopramide.