The present invention discloses the structure, preparation methods and uses of a series of novel polyheterocyclic based compounds (Ia-Ib and IIa-IIb) that are highly effective for inhibiting hepatitis C virus (HCV):where the structural variables are defined herein. The present invention is also provides a method of treating HCV infection by the polyheterocyclic based HCV inhibitory compounds, compositions and therapeutic methods.
