Inhibitors of HCV NS5A

A pharmaceutical composition comprising a compound of formula IIIe and one or more pharmaceutically acceptable excipients or vehicles,

• wherein the compound of formula IIIe has the structure:
• or a pharmaceutically acceptable salt thereof, wherein:
• X and X′ are each —CH2—;
• Xb and Xc are each —C—;
• each Ra is hydrogen;
• each r is 3;
• Z and Z′ are each independently —U—(CR42)t—NR5—U—O—R8, wherein,
• each U is independently selected from the group consisting of —C(O)—, —C(S)— and —S(O)2—,
• each R4 and R5 is independently selected from the group consisting of hydrogen, C1 to
• C8 alkyl, C1 to C8 heteroalkyl, cycloalkyl, heterocycle, aryl, heteroaryl and aralkyl,
• R8 is hydrogen or C1 to C8 alkyl, and
• t is independently 0, 1, 2, 3, or 4.