New Carbocyclic Amino Acid Derivatives Inhibit Infection Caused by Highly Pathogenic Influenza A Virus Strain (H5N1).

New amino acid derivatives with carbocycles of adamantine and quinaldic acid were synthesized and their in vitro antiviral activity against influenza A/H5N1 virus was evaluated. Experiments on cultured embryonic porcine kidney epithelial cells showed that amino acid derivatives suppressed viral replication. Tret-butyloxycarbonyl-DL-methionylsulfonyl-1-adamantayl ethylamine and benzyloxycarbonyl-L-trypthophanyl-1-adamantayl ethylamine compounds demonstrated high activity in all in vitro experiments. Moreover, some compounds showed virucidal activity against influenza A/H5N1 virus.