Discovery of novel piperidine-substituted indolylarylsulfones as potent HIV NNRTIs via structure-guided scaffold morphing and fragment rearrangement

To further explore the chemical space around the entrance channel of HIV-1 reverse transcriptase (RT), a series of novel indolylarylsulfones (IASs) bearing N-substituted piperidine at indole-2-carboxamide were identified as potent HIV NNRTIs by structure-guided scaffold morphing and fragment rearrangement. All the IASs exhibited moderate to excellent potency against wild-type HIV-1 with EC50 values ranging from 0.62 μM to 0.006 μM 8 (EC50 = 6 nM) and 18 (EC50 = 9 nM) were identified as the most potent compounds, which were more active than NVP and DLV, and reached the same order of EFV and ETV. Furthermore, most compounds maintained high activity agaist various single HIV-1 mutants (L100I, K103N, E138K, Y181C) as well as one double mutant (F227L/V106A) with EC50 values in low-micromolar to double-digit nanomolar concentration ranges. Especially, 8 displayed outstanding potency against L100I (EC50 = 17 nM with a 2.8-fold resistance ratio) and 18 was relatively more potent to E138K mutant (EC50 = 43 nM with a 4.7-fold resistance ratio). Preliminary SARs and molecular modeling studies were also discussed in detail, which may provide valuable insights for further optimization.