Human immunodeficiency virus type 1 (HIV-1) Rev protein facilitates the export of viral RNA from nucleus to cytoplasm, which is a key step in HIV-1 pathogenesis and transmission. In this study, we have screened a commercial library and identified the hit compound 1 bearing a benzenesulfonamide quinoline scaffold that inhibited Rev activity and HIV-1 infectivity. Compounds bearing this scaffold were synthesized and their SAR was studied. We identified compound 20 with low toxicity and potent activity to inhibit HIV-1 replication by affecting Rev function.

•A class of benzimidazole derivatives was explored as potential anti-HIV-1 replication agents.•Compound 14 and 26 inhibit the HIV-1 replication with an IC50 value of 2.30 nM and 60.52 nM.•Compound 14 and 26 protect APOBEC3G from degradation by HIV-1 vif protein in 293T cells.•Compound 14 and 26 show low toxicity in the acute toxicity assay.Human APOBEC3G (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G, A3G) is a potent restriction factor against human immunodeficiency virus type 1 (HIV-1) by inducing hypermutation of G to A in viral genome after its incorporation into virions. HIV-1 Vif (Virion Infectivity Factor) counteracts A3G by inducing ubiquitination and proteasomal degradation of A3G protein. Vif-A3G axis therefore is a promising therapeutic target of HIV-1. Here we report the screening, synthesis and SAR studies of benzimidazole derivatives as potent inhibitors against HIV-1 replication via protecting A3G protein. Based on the steep SAR of the benzimidazole scaffold, we identified compound 14 and 26 which provided the best potency, with IC50 values of 3.45 nM and 58.03 nM respectively in the anti-HIV-1 replication assay in H9 cells. Compound 14 and 26 also afforded protective effects on A3G protein level. Both compounds have been proved to be safe in acute toxicological studies. Taken together, we suggest that these two benzimidazole derivatives can be further developed as a new category of anti-HIV-1 leads.

Although combined antiretroviral therapy (cART) successfully decreases plasma viremia to undetectable levels, the complete eradication of human immunodeficiency virus type 1 (HIV-1) remains impractical because of the existence of a viral reservoir, mainly in resting memory CD4+ T cells. Various cytokines, protein kinase C activators, and histone deacetylase inhibitors (HDACi) have been used as latency-reversing agents (LRAs), but their unacceptable side effects or low efficiencies limit their clinical use. Here, by a mutation accumulation strategy, we generated an attenuated HIV-1 Tat protein named Tat-R5M4, which has significantly reduced cytotoxicity and immunogenicity, yet retaining potent transactivation and membrane-penetration activity. Combined with HDACi, Tat-R5M4 activates highly genetically diverse and replication-competent viruses from resting CD4+ T lymphocytes isolated from HIV-1-infected individuals receiving suppressive cART. Thus, Tat-R5M4 has promising potential as a safe, efficient, and specific LRA in HIV-1 treatment.

Human immunodeficiency virus type 1 (HIV-1) Rev protein facilitates the export of viral RNA from nucleus to cytoplasm, which is a key step in HIV-1 pathogenesis and transmission. In this study, we have screened a commercial library and identified the hit compound 1 bearing a benzenesulfonamide quinoline scaffold that inhibited Rev activity and HIV-1 infectivity. Compounds bearing this scaffold were synthesized and their SAR was studied. We identified compound 20 with low toxicity and potent activity to inhibit HIV-1 replication by affecting Rev function.