An orally bioavailable oxime ether capsid binder with potent activity against human rhinovirus.

A series of capsid-binding compounds was screened against human rhinovirus (HRV) using a CPE based assay. The ethyl oxime ether 14 was found to have outstanding anti-HRV activity (median IC(50) 4.75 ng/mL), and unlike the equivalent ethyl ester compound 3 (Pirodavir), it has good oral bioavailability, making it a promising development candidate. Compound 14 illustrates that an oxime ether group can act as a metabolically stable bioisostere for an ester functionality.