Antifungal activities of hop bitter resins and related compounds.

Humulone, lupulone and related compounds were found to have antifungal activities. The activities of these compounds were tested to determine their structure-activity relationships. As a result, it was found that the six-membered compounds had antifungal activities against Trichophyton spp., whereas, the flve-membered compounds were inactive. Among the compounds tested, 3-isopentenylphlorisovalerophenone 12 showed the highest activity, being almost the same as griseofulvin against Trichophyton spp. 12 also had potent activity against Candida, Fusarium, Mucor and Staphylococcus spp. It is suggested that the activity of 12 was significantly affected by the structue of its acyl group.