Anti-influenza activity of monoterpene-derived substituted hexahydro-2H-chromenes.

The antiviral activity of 4-hydroxy-hexahydro-2H-chromenes and 4-fluorine-hexahydro-2H-chromenes with an aromatic substituent, synthesized from monoterpene (-)-verbenone, was studied for the first time. Five of 11 (45 per cent) of 4-hydroxy-hexahydro-2H-chromene-type compounds have been found to exhibit antiviral activity against influenza A virus of subtype H1N1pdm09. Although a portion of active compounds among 4-fluorine-containing series was fewer, just compound 5i that contains a fluorine substituent exhibited more potent anti-influenza activity along with low cytotoxicity. Thus two new promising types of antiviral compounds were identified.