Non-nucleoside reverse transcriptase inhibitors (NNRTIs) represent an indispensable part of anti-HIV-1 therapy. To discover novel HIV-1 NNRTIs with increased drug resistance profiles and improved pharmacokinetic (PK) properties, a series of novel diarylpyrimidine derivatives were generated via the cocrystal structure-based drug design strategy. Among them, 36a exhibited outstanding antiviral activity against HIV-1 IIIB and a panel of mutant strains (L100I, K103N, Y181C, Y188L, E138K, F227L + V106A, and RES056), with EC 50 ranging from 2.22 to 53.3 nM. Besides, 36a was identified with higher binding affinity (K D = 2.50 μM) and inhibitory activity (IC 50 = 0.03 μM) to HIV-1 RT. Molecular docking and molecular dynamics simulation were performed to rationalize the design and the improved drug resistance of these novel inhibitors. Additionally, 36a•HCl exhibited favorable PK (T 1/2 = 5.12 h, F = 12.1%) and safety properties (LD 50 > 2000 mg/kg). All these suggested that 36a•HCl may serve as a novel drug candidate anti-HIV-1 therapy.

This study presents proof of concept for designing a novel HIV-1 covalent inhibitor targeting the highly conserved Tyr318 in the HIV-1 non-nucleoside reverse transcriptase inhibitors binding pocket to improve the drug resistance profiles. The target inhibitor ZA-2 with a fluorosulfate warhead in the structure was found to be a potent inhibitor (EC50 = 11–246 nM) against HIV-1 IIIB and a panel of NNRTIs-resistant strains, being far superior to those of NVP and EFV. Moreover, ZA-2 was demonstrated with lower cytotoxicity (CC50 = 125 µM). In the reverse transcriptase inhibitory assay, ZA-2 exhibited an IC50 value of 0.057 µM with the ELISA method, and the MALDI-TOF MS data demonstrated the covalent binding mode of ZA-2 with the enzyme. Additionally, the molecular simulations have also demonstrated that compounds can form covalent binding to the Tyr318.