Potent and selective vasopressin V1B antagonist (Ki values are 3.7 and 1.3 nM for native and recombinant rat V1b receptors, respectively). Displays >70-fold selectively for rat V1B over V1A, V2 oxytoxin and a range of other receptors and ion channels. Inhibits AVP-induced glucagon release in In-R1-G9 α-pancreatic cells in vitro. Inhibits stress-induced ACTH release and exhibits anxiolytic-like effects in anxiety models. Orally bioavailable. Purity 98%. MW (observed): 630.11