Background: Influenza is a disease of significant morbidity and mortality, the number of anti-influenza drugs is small; many of them stimulate the appearance of resistant strains. In this work, we demonstrate activity of some usnic acid (UA) derivatives against influenza virus in vitro and in vivo.
Methods: Organic synthesis was used to prepare compounds. Antiviral activity of the compounds in vitro was evaluated by their ability to decrease the virus titer on Madin-Darby Canine Kidney cells. In vivo activity was evaluated by decrease of mortality and index of protection.
Results: Compounds were tested against a broad spectrum of influenza virus strains and showed activity against all used strains. One compound, [5] (valine enamine of UA), also significantly reduced lethality of infected animals and does not give rise to the appearance of resistant strains. Additional studies showed that hepatotoxicity of compound [5] is reduced comparatively to UA.
Conclusion: Our results suggest that valine enamine of UA could be a potential candidate for the development of a new anti-influenza therapy.
Keywords: Compounds; influenza; inhibitors; orthomyxoviridae; respiratory infections.
© The Author(s) 2016.