abstract |
The present invention relates to 2'-substituted nucleoside derivatives of formula (i): and pharmaceutically acceptable salts thereof, wherein a, b, x, r1, r2 and r3 are as defined herein. The present invention further provides compositions comprising at least one 2'-substituted nucleoside derivative, and methods of using the 2'-substituted nucleoside derivatives for treating or preventing vhc infection in a patient. |