and no attractive interaction occurs between the P4 and P5 subsites with the S4 and S5 pockets. Note that only these P1–P3subsites were considered for the relative interaction because the non-prime site are more important than the prime site for interacting with the NS2B/NS3pro, as discussed before. These theoretically derived results broadly agree with the reported experimental data [39] that the preference of each subsite for interacting with NS2B/NS3pro are R > K, R > T > Q/N/K, K > R > N and Nle > L > K for P1, P2, P3 and P4, respectively.