Abstract
Various conjugated compounds containing a coumarin moiety and a heterocyclic nucleus were synthesized. Their activity against hepatitis C virus was tested on subgenomic replicon replication in Huh 5-2 cells. Some heterobicycle–coumarin conjugates with the ‒S‒CH2‒ linker were found to possess appealing antiviral activities. The sulfur atom in these conjugated compounds was found to be an essential element to their antiviral activity.