To address drug resistance to influenza virus neuraminidase inhibitors (NAIs), a series of novel boron-containing N-substituted oseltamivir derivatives were designed and synthesized to target the 150-cavity of neuraminidase (NA). In NA inhibitory assays, it was found that most of the new compounds exhibited moderate inhibitory potency against the wild-type NAs. Among them, compound 2c bearing 4-(3-boronic acid benzyloxy)benzyl group displayed weaker or slightly improved activities against group-1 NAs (H1N1, H5N1, H5N8 and H5N1-H274Y) compared to that of oseltamivir carboxylate (OSC). Encouragingly, 2c showed 4.6 times greater activity than OSC toward H5N1-H274Y NA. Moreover, 2c exerted equivalent or more potent antiviral activities than OSC against H1N1, H5N1 and H5N8. Additionally, 2c demonstrated low cytotoxicity in vitro and no acute toxicity at the dose of 1000 mg/kg in mice. Molecular docking of 2c was employed to provide a possible explanation for the improved anti-H274Y NA activity, which may be due to the formation of key additional hydrogen bonds with surrounding amino acid residues, such as Arg152, Gln136 and Val149. Taken together, 2c appeared to be a promising lead compound for further optimization.
为了解决流感病毒神经氨酸酶抑制剂(NAIs)的耐药性问题,设计并合成了一系列新型含硼N-取代奥司他韦衍生物,以针对神经氨酸酶(NA)的150-腔。在NA抑制实验中发现,大多数新化合物对野生型NA表现出中等的抑制效力。其中,带有4-(3-硼酸苄氧基)苯基基团的2c化合物在对组1 NA(H1N1,H5N1,H5N8和H5N1-H274Y)的抑制活性方面显示出比奥司他韦羧酸盐(OSC)更弱或略有改善。令人鼓舞的是,2c对H5N1-H274Y NA的活性比OSC高出4.6倍。此外,2c对H1N1,H5N1和H5N8的抗病毒活性相当或更强于OSC。此外,2c在体外表现出低细胞毒性,在小鼠1000 mg / kg的剂量下没有急性毒性。采用2c的分子对接来解释其改善的抗H274Y NA活性的可能原因,这可能是由于与周围氨基酸残基(如Arg152,Gln136和Val149)形成关键的额外氢键。综上所述,2c似乎是进一步优化的有前途的先导化合物。