A Pyridazine Series of α2/α3 Subtype Selective GABA_AAgonists for the Treatment of Anxiety

The development of a series of GABA(A) alpha 2/alpha 3 subtype selective pyridazine based benzodiazepine site agonists as anxiolytic agents with reduced sedative/ataxic potential is described, including the discovery of 16, a remarkably alpha 3-selective compound ideal for in vivo study. These ligands are antagonists at the alpha 1 subtype, with good CNS penetration and receptor occupancy, and excellent oral bioavailability.