Virus inhibition by some amino acid analogs

Several α-amino acid analogs were tested as inhibitors of the propagation of a number of viruses in the chick embryo. Glycyl-6-methyl- dl-tryptophan did not inhibit the growth of any of the viruses tested, α-Aminoisobutanesulfonic acid was found to be effective against two strains of infections, bronchitis virus as well as influenza A virus, no activity being demonstrated against Newcastle disease or vaccinia viruses. A comparative study of the inhibition of influenza A virus by α-amino-β-phenylethanesulfonic acid and two of its derivatives revealed that the formation of the glycine peptide derivative resulted in markedly decreased virus inhibitory activity, while a urea derivative was equally effective as a virus inhibitor.