Follow on-based optimization of the biphenyl-DAPYs as HIV-1 nonnucleoside reverse transcriptase inhibitors against the wild-type and mutant strains.

The present work follows our preliminary discovery of biphenyl diarylpyrimidines (DAPYs) as HIV-1 nonnucleoside reverse transcriptase inhibitors. Further structural optimization of biphenyl-DAPYs led to the identification of a new series of biphenyl-substituted thiophene[3,2-d]pyrimidine analogues by a scaffold-hopping strategy. Biological evaluation of this series showed that these compounds possessed up to single-digit nanomolar potency (EC50 = 7.8-526.2 nM) and prominently low toxicity (CC50 = 18.5-280.8 μM) against wild-type (WT) HIV-1-infected cells. Furthermore, the results also demonstrated that compounds 29-32 exhibited high, broad-spectrum antiviral effects against clinically observed HIV-1 mutants. Specifically, compound 30, which had the highest selectivity index (SI = 16094) and the best anti-reverse transcriptase ability (IC50 = 39 nM), displayed marked inhibitory activity (EC50 = 13.5, 9.4, 17.0, 52.0, and 58.2 nM) against WT, K103N, E138K, L100I, Y181C mutants and moderate activity against double mutants. This study provides important avenues for the further design of HIV-1 inhibitors.