Potent muscarinic DREADD agonist (pEC50 values are 8.91, 8.48 and 7.77 for hM1Dq, hM3Dq and hM4Di in vitro, respectively). Exhibits > 10-fold higher affinity for hM1Dq and hM4Di compared to wild type receptors. Also displays little to no activity at wild type M3 receptors. Activates neurons expressing hM3Dq DREADDS and inhibits activity in neurons expressing hM4Di in vivo. Displays excellent brain permeability. Water soluble salt also available, DREADD agonist 21 hydrochloride (Cat. No. 6422). Purity 98%. MW (observed): 278.35