Design, Synthesis, and Docking Studies of Thioimidazolyl Diketoacid Derivatives Targeting HIV-1 Integrase

Background: Integrase enzyme is a validated drug target to discover novel structures as anti-HIV-1 agents. Objective: This study aimed at developing a novel series of thioimidazolyl diketoacid derivatives characterizing various substituents at N-1 and 2-thio positions of the central ring as HIV-1integrase inhibitors. Methods: In this study, eighteen novel thioimidazolyl DKA derivatives were synthesized in a fivestep parallel procedure and tested in vitro for the inhibition of both IN ST reaction and the singlecycle HIV-1 replication in HeLa cell culture. Results: The obtained molecules were evaluated using the enzyme assay, displaying promising integrase inhibitory activity with IC50 values ranging from 0.9 to 7.7 mM. The synthesized compounds were also tested for antiviral activity and cytotoxicity using HeLa cells infected by the single-cycle replicable HIV-1 NL4-3. Conclusion: The most potent compound was found to be 18i with EC50 = 19 μM, IC50 = 0.9 μM, and SI = 10.5. Docking studies indicated that the binding mode of the active molecule is well aligned with the known HIV-1integrase inhibitor.