Identification and pharmacological profile of SPP1, a potent, functionally selective and brain penetrant agonist at muscarinic M1 receptors.

We report the discovery of SPP1, a novel, functionally selective, brain penetrant partial orthosteric agonist at M1 receptors, identified by a novel receptor occupancy assay. SPP1 is amenable to in vitro and in vivo study and provides a valuable research tool to further probe the role of M1 receptors in physiology and disease.