CSP 2503

CSP-2503 is a potent and selective 5-HT_1A receptor agonist, 5-HT_2A receptor antagonist, and 5-HT₃ receptor antagonist of the phenylpiperazine class. First synthesized in 2003, it was designed based on computational models and QSAR studies. In rat studies, CSP-2503 has demonstrated anxiolytic effects, and thus has been suggested as a treatment for anxiety in humans with a multimodal mechanism of action.