Scaffold hopping yields novel furo[3,2-d]pyrimidine NNRTIs with optimized antiviral potency, enhanced selectivity, and reduced hERG liability

Considering the exceptional anti-HIV-1 potency of rilpivirine (RPV) against diverse mutant strains and its remarkable human ether-a-go-go related gene (hERG) potassium channel inhibition (IC 50 = 0.50 μmol/L) as well as low selectivity (SI = 3989), a series of novel furo-[3,2- d ]pyrimidine derivatives were rationally designed through a scaffold hopping strategy. Encouragingly, compound 10 revealed a striking reduction in hERG channel inhibition (IC 50 > 30 μmol/L) and significant increase in selectivity (SI = 161580). Notably, 10 exhibited excellent antiviral activity against various HIV-1 strains (EC 50 = 1.9−46.3 nmol/L). In particular, 10 displayed prominent inhibitory potency against Y188L (EC 50 = 15.5 nmol/L) and F227L+V106A strain (EC 50 = 8.7 nmol/L), which was superior to those of RPV (EC 50 (Y188L) = 79.4 nmol/L, EC 50 (F227L+V106A) = 81.6 nmol/L). Besides, no apparent cytotoxicity (CC 50 = 314.8 μmol/L) and negligible suppression of CYP isoenzymes were detected. Overall, these findings illustrated that 10 was a potentially promising NNRTI for HIV-1 therapy.