N-(3,3a,4,4a,5,5a,6,6a-Octahydro-1,3-dioxo-4,6- ethenocycloprop[f]isoindol-2-(1H)-yl)carboxamides: Identification of novel orthopoxvirus egress inhibitors.

A series of novel, potent orthopoxvirus egress inhibitors was identified during high-throughput screening of the ViroPharma small molecule collection. Using structure--activity relationship information inferred from early hits, several compounds were synthesized, and compound 14 was identified as a potent, orally bioavailable first-in-class inhibitor of orthopoxvirus egress from infected cells. Compound 14 has shown comparable efficaciousness in three murine orthopoxvirus models and has entered Phase I clinical trials.