Design, synthesis and evaluation of novel phenyl propionamide derivatives as non-nucleoside hepatitis B virus inhibitors.

As an ongoing search for potent non-nucleoside anti-HBV agents with novel structures, we described a series of phenyl propionamide derivatives (3a-b, 4a-e, 7a-g, 8a-h and 9a-b) by pharmacophore fusion strategy in the present work. All the compounds exhibited an anti-HBV activity to some extent. Among them, compounds 8d and 9b displayed most potent anti-HBV activity with IC values on HBV DNA replication of 0.46 and 0.14 μM, respectively. And the selective index values of 8d and 9b were more than 217.39 and 153.14, suggesting that 8d and 9b exhibited favorable safety profiles. Interestingly, 8d and 9b possessed significantly antiviral activities against lamivudine and entecavir resistant HBV mutants with IC values of 0.77 and 0.32 μM. Notably, preliminary anti-HBV action mechanism studies showed that 8d could inhibit intracellular HBV pgRNA and RT activity of the HBV polymerase. Molecular docking studies suggested that compound 8d could fit into the dimer-dimer interface of HBV core protein by hydrophobic interaction. In addition, in silico prediction of physicochemical properties showed that 8d conformed well to the Lipinski's rule of five, suggesting its potential for use as a drug like molecule. Taken together, 8d possessed significantly anti-HBV activity, low toxicity, diverse anti-HBV mechanism and favorable physicochemical properties, and warranted further investigation as a promising non-nucleoside anti-HBV candidate.