Figure 1.
Molecular structures of the NS3-4A serine protease inhibitors VX-950 (telaprevir) and SCH 503034 (boceprevir) as well as of the co-crystallized protease ligands CPX and SCH 446211. The P1 to P4 and P'1 to P'2 groups are numbered according to the nomenclature of Schechter and Berger [61]. Residues surrounding a cleavage site are designated from the amino- to carboxyl-terminus, that is, P4-P3-P2-P1 P'1-P'2-P'3-P'4, with the scissile bond between P1 and P'1. They are annotated only for SCH 446211.