Structure-based exploration and exploitation of the S 4 subsite of norovirus 3CL protease in the design of potent and permeable inhibitors

Eur J Med Chem. 2017 Jan 27;126:502-516. doi: 10.1016/j.ejmech.2016.11.027. Epub 2016 Nov 14.


Human noroviruses are the primary cause of epidemic and sporadic acute gastroenteritis. The worldwide high morbidity and mortality associated with norovirus infections, particularly among the elderly, immunocompromised patients and children, constitute a serious public health concern. There are currently no approved human vaccines or norovirus-specific small-molecule therapeutics or prophylactics. Norovirus 3CL protease has recently emerged as a potential therapeutic target for the development of anti-norovirus agents. We hypothesized that the S4 subsite of the enzyme may provide an effective means of designing potent and cell permeable inhibitors of the enzyme. We report herein the structure-guided exploration and exploitation of the S4 subsite of norovirus 3CL protease in the design and synthesis of effective inhibitors of the protease.

Keywords: 3CL protease; Norovirus; Optimization; S4 subsite.

MeSH terms

  • Cell Line
  • Drug Design*
  • Humans
  • Models, Molecular
  • Norovirus / drug effects
  • Norovirus / enzymology*
  • Norovirus / physiology
  • Peptide Hydrolases / chemistry*
  • Peptide Hydrolases / metabolism*
  • Permeability
  • Protease Inhibitors / chemistry*
  • Protease Inhibitors / metabolism
  • Protease Inhibitors / pharmacology*
  • Protease Inhibitors / toxicity
  • Protein Conformation
  • Structure-Activity Relationship
  • Virus Replication / drug effects


  • Protease Inhibitors
  • Peptide Hydrolases