Inhibition of HCV Replicon Cell Growth by 2-Arylbenzofuran Derivatives Isolated from Mori Cortex Radicis

Abstract

Medicinal herbs are increasingly used in the search for safe and efficient drug candidates for hepatitis C virus infection. In this study, we have investigated the anti-HCV effect of compounds from Mori Cortex Radicis. During a screening for extracts with anti-HCV affinity from medicinal plants (173 species), the methanol extract of Mori Cortex Radicis was selected. Fractionation of the extract by monitoring antiviral activity with a replicon cell-based assay resulted in the isolation of five compounds, mulberroside C (1), moracin P (2), moracin O (3), moracin M (4) and mulberrofuran K (5) from the ethyl acetate-soluble fraction. Compounds 1 ∼ 4 showed significant inhibitory activities. Compounds 2 and 3 showed potent inhibitory activity (IC₅₀ 35.6 μM, 80.8 μM, respectively) in the replicon cell assay, which was confirmed by NS3 helicase inhibitory activity (IC₅₀ 42.9 μM, 27.0 μM, respectively).

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1 These authors coordinated equally with this paper