PROBLEM TO BE SOLVED: To provide an HCV (hepatitis C virus) polymerase inhibiting compound and a composition including a therapeutically effective amount of the compound.SOLUTION: This invention relates to the compound having formula (I). This invention also relates to methods for inhibiting HCV polymerase, inhibiting HCV viral replication, and treating or preventing HCV infection. Processes for making the compounds and the synthetic intermediates employed in the processes, are also provided.COPYRIGHT: (C)2011,JPO&INPIT【課題】HCV(C型肝炎ウイルス)ポリメラーゼ阻害性化合物および治療上有効量の該化合物を含む組成物の提供。【解決手段】下記式(I)を有する化合物。C型肝炎ウィルス(HCV)ポリメラーゼの阻害方法、HCVウィルス複製の阻害方法、ならびにHCV感染の治療または予防方法。前記化合物の製造方法ならびにそれらの方法で用いられる合成中間体。【選択図】なし