SUBSTITUTED PURINE NUCLEOSIDES, PHOSPHOROAMIDATE AND PHOSPHORODIAMIDATE DERIVATIVES FOR TREATMENT OF VIRAL INFECTIONS

摘要

This invention is directed to phosphoroamidate and phosphorodiamidate derivatives including the compounds of formula (I) having the structure wherein U, V, W, Z, R1, X1, X2, and Y are defined herein. These compounds and pharmaceutical compositions containing these compounds are useful in the treatment of viral infections in mammals infected by a virus in the Flaviviridae family of viruses, in particular hepatitis C virus (HCV). The compounds of this invention may be prepared by various methods known in the art of organic chemistry in general and nucleoside and nucleotide analog synthesis in particular.