Antiviral action of derivatives of omega-aminoacetophenone.

Numerous structural analogues of 3-amino-4-hydroxy-omega-methylaminoacetophenone were tested for their effect on the multiplication of influenza virus (FM(1) strain) in embryonated eggs, infected via the allantoic cavity. Antiviral activity was found in omega-aminoacetophenones containing an amino and hydroxyl group in the aromatic nucleus in the ortho or para positions to each other. The most powerful antiviral activity was found in the series of omega-alkylamino-5-amino-2:4-dihydroxyacetophenones. Derivatives of acetophenone with other substituents in the aromatic nucleus or in the aliphatic chain were without activity. In vitro, several analogues inactive in the egg test, as well as those which were active, exerted a virucidal and to a lesser extent a haemagglutinin-destroying action. Antiviral action in the allantoic test could not be prevented or inhibited by simultaneous administration of reducing substances, or of some amino-acids or vitamins. No inhibition of virus multiplication occurred in embryonated eggs infected via the yolk sac, or in mice infected intranasally with FM(1) virus. The activity in the allantoic test could be explained by the virucidal action of the compounds on the virus present in the allantoic fluid. No satisfactory interpretation of the empirical relationship between chemical structure and antiviral activity could be found.