Antiviral activity of selected biguanide derivatives

Biguanide and twenty N1-substituted biguanide derivatives were examined for in vitro antiviral activity against polio 1, vaccinia and influenza A viruses. Only the alkyl-derivatives with 4 carbon atoms in the alkyl chain were active against polio virus; on vaccinia and influenza viruses both short and long chain alkyl-derivatives are effective, and activity increases as the length of the alkyl chain grows from 1 to 4 carbon atoms. These results agree with the ones of previous investigations on the antitumoral activity of the same compounds. Among the aryl-derivatives, benzyl-biguanide is effective on both vaccinia and influenza viruses, while phenyl-biguanide is not. Adding a methyl group, their activity is not modified. Diaryl-derivatives are active only on vaccinia virus; cycloaliphatic-derivatives are completely inactive. © 1974 The Italian Pharmacological Society.