abstract |
This invention is directed to novel compounds of formula (I) having the structure (I) wherein U, V, W, Z, R 1 , X 1 , X 2 , and Y are defined herein. The compounds of formula (I) and pharmaceutical compositions containing these compounds are useful in the treatment of viral infections in mammals mediated, at least in part, by a virus in the Flaviviridae family of viruses, in particular hepatitis C virus (HCV). |