Discovery of potent, metabolically stable purine CRF-1 antagonists with differentiated binding kinetic profiles

Abstract

Optimisation of the potency of a bicyclic CRF antagonist whilst retaining metabolic stability is described. A core change and incorporation of metabolically stable lipophilic groups resulted in a further potency gain without increasing metabolic liability. Pharmacological investigation of binding kinetics led to the identification of compound 25, a sub-nanomolar CRF-1 antagonist with slow dissociation kinetics and an encouraging pharmacokinetic profile.