The present invention is directed to compounds, compositions and methods for treating or preventing Flaviviridae family of viruses (including HCV, Yellow fever, Dengue, Chikungunya and West Nile virus), RSV and influenza infection and cancer in human subjects or other animal hosts. The compounds are as also pharmaceutically acceptable, salts, prodrugs, and other derivatives thereof as pharmaceutical compositions and methods for treatment or prevention of HCV infection.
