Synthesis and biological investigation of triazolopyridinone derivatives as potential multireceptor atypical antipsychotics.

A series of triazolopyridinone derivatives originating from the antidepressant trazodone was designed and pharmacologically evaluated. Most of the compounds with a multireceptor functional profile exhibited high potency at the D2, 5-HT1A, and 5-HT2A receptors. Compounds S1, S3, S9 and S12 were selected for further evaluation of druggable potential. Among these compounds, S1, as a D2 receptor partial agonist, demonstrated very potent inhibition of quipazine-induced head-twitch response, which validated its 5-HT2A receptor antagonistic efficacy in vivo. S1 also demonstrated a dose-dependent effect on PCP-induced hyperactivity when administered orally. Thus, S1 endowed with a triazolopyridinone scaffold represents a valuable lead for the development of novel atypical antipsychotics.