4-Thio substituted coumarin derivatives, 4,5-dithio substituted coumarin
derivatives, and coumarin dimers are provided, as well as processes for
their preparation. The invention also provides a method and composition
for the treatment of hepatitis C virus (HCV) by adiministering 4-thio
substituted coumarin derivatives, 4,5-dithio substituted coumarin
derivatives, and coumarin dimers.