| abstract |
The present invention provides a compound of formula I: n n n n n n n n n n or a pharmaceutically acceptable salt thereof, wherein R 1 is defined herein, which is a 2′-branched nucleoside useful for the treatment or prevention of viral infections, particularly dengue virus, yellow fever virus, West Nile virus, Japanese encephalitis virus, tick-borne encephalitis virus, Kunjin virus, Murray Valley encephalitis, St Louis encephalitis, Omsk hemorrhagic fever virus, bovine viral diarrhea virus, Zika virus and Hepatitis C virus. |