Disclosed are compounds comprising an azasugar attached to a heterocyclic base, including pharmaceutically acceptable salts thereof, suitable for use in inhibiting viral RNA polymerase activity or viral replication, and treating viral infections. The compounds are characterized, in part, by favorable pharmacokinetics for the active pharmaceutical ingredient, particularly in conjunction with enteral administration, including, in particular, oral administration. Also disclosed are pharmaceutical compositions comprising one or more compounds mentioned above, or pharmaceutically acceptable salts thereof, as well as methods for preparing same. Also provided are methods for inhibiting viral RNA polymerase activity, viral replication, and treating viral infections.