Pyrazinobenzodiazepines as Potent Nonpeptide Vasopressin Receptor Antagonists

We have identified a novel series of tricyclic pyrazinobenzodiazepines, represented by general structure 2, as potent vasopressin receptor antagonists. For example, 3 binds with high affinity to human V2 receptors and is very selective relative to V1a receptors. Compound (R)-(+)-3 exhibited pronounced aquaretic activity in rats and dogs on oral administration.