Disclosed herein are nucleoside phosphoramidates and their use as agents for treating viral diseases. These compounds are inhibitors of RNA-dependent 5 RNA viral replication and are useful as inhibitors of HCV NS5B polymerase, as inhibitors of HCV replication and for treatment of hepatitis C infection in mammals.本文所揭露的為核苷胺基磷酸酯以及它們作為治療病毒疾病之用途。這些組成物為RNA-依賴性5 RNA病毒複製的抑制劑,並且作為HCV NS5B聚合酶抑制劑、作為HCV複製之抑制劑與針對治療哺乳類動物之C型肝炎感染為有效的。