Structure-based design of novel 2,4,5-trisubstituted pyrimidine derivatives as potent HIV-1 NNRTIs by exploiting the tolerant regions in NNTRIs binding pocket.

To promote the development of the new generation of HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs), a series of novel 2,4,5-trisubstituted pyrimidine derivatives targeting the "tolerant region I″ and "tolerant region II" of NNRTI binding pocket (NNIBP) were designed through multi-site binding strategy. Among them, 13a was demonstrated with an improved potency against wild-type (WT) and a panel of mutant HIV-1 strains with EC50 values ranging from 0.0062 to 0.25 μM, being superior to that of efavirenz (EFV, EC50 = 0.0080-0.37 μM). In addition, 13a was proved to have low cytotoxicity (CC50 = 160.7 μM) and high SI values (SI = 25254). Further HIV-1 RT inhibition assay demonstrated that 13a is a classical NNRTI with an IC50 value of 0.41 μM. Molecular docking and molecular dynamics simulations results illustrated its binding mode with HIV-1 RT. Overall, these enchanting results illuminated the potential of 13a as a promising lead for the development of the new generation HIV-1 NNRTIs drugs.