Provided herein are compounds, compositions and methods for the treatment of liver cancer such as hepatocellular carcinoma, cholangiocarcinoma, or biliary tract cancer. In certain embodiments, compounds and compositions of nucleoside derivatives are disclosed, which can be administered either alone or in combination with other anti-cancer agents. In certain embodiments, the compounds are nucleoside analogs of Formula I: (I); or a pharmaceutically acceptable salt thereof, wherein Base, Z1, Z2, Z3, Z4, V, W, X, Ar, R1 and R2 are as described herein.