DREADD agonist 21 activates hM3Dq (EC50 = 1.7 nM), a designer receptor exclusively activated by designer drugs (DREADD) derived from the human muscarinic acetylcholine M3 receptor.1 It does not agonize the hM3 receptor and displays relatively weaker binding affinities for serotonin 5-HT2A, 5-HT2C, α1A-adrenergic, and histamine H1 receptors (Kis = 66, 170, 280, and 6 nM, respectively).1
1.Chen, X., Choo, H., Huang, X.P., et al.The first structure-activity relationship studies for designer receptors exclusively activated by designer drugsACS Chem. Neurosci.6(3)476-484(2015)