Discovery of nitropyridine derivatives as potent HIV-1 non-nucleoside reverse transcriptase inhibitors via a structure-based core refining approach

Abstract

As a continuation of our efforts to discover and develop back-up analogs of DAPYs, novel substituted nitropyridine derivatives were designed via a structure-based core refining approach, synthesized and evaluated for their in vitro HIV-1 activity in MT-4 cells. Preliminary biological evaluation indicated that most of the compounds exhibited marked inhibitory activity against wild-type HIV-1 IIIB. Most notably, the compound 7b was identified as the most promising candidate in inhibiting HIV-1 replication with an EC50 value of 0.056 μM and a selective index (SI) of 1251, which were much better than those of NVP (EC₅₀ = 0.23 μM) and DLV (EC₅₀ = 0.51 μM). Some other compounds, 7k, 7c, 7j and 7e, were also endowed with a favorable anti-HIV-1 potency (EC₅₀ = 0.034, 0.11, 0.11 and 0.16 μM, respectively). Some antivirally active compounds also showed moderate inhibitory activity against RT. Preliminary structure-activity relationships (SARs) and molecular modeling of these new analogs provide valuable avenues for future molecular optimization.

Keywords: Bioactivity; Drug design; HIV-1; NNRTIs; Organic synthesis; Pyridine; Reverse transcriptase.