Antifungal activity of sesquiterpene lactones

Forty-five sesquiterpene lactones were screened for their antifungal activities against Microsporum cookei, Trichophyton mentagrophytes and Fusarium sp. The screening tests showed that a majority of sesquiterpene examined possess at least weak antifungal activity, the eudesmanolides being the most active. The antifungal activity of sesquiterpene lactones cannot be explained by the presence or absence of two potential active sites (the exocyclic methylene and, in pseudoguaianolides, a β-unsubstituted cyclopentenonel) but other functions must play a role in enhancing or reducing this activity.