Hepatitis C virus NS3-4A serine protease inhibitors: SAR of P2′ moiety with improved potency

Abstract We have discovered that introduction of appropriate amino acid derivatives at P 2 ′ position improved the binding potency of P 3 -capped α-ketoamide inhibitors of HCV NS3 serine protease. X-ray crystal structure of one of the inhibitors ( 43 ) bound to the protease revealed the importance of the P 2 ′ moiety.