Wasalexins A and B, new phytoalexins from wasabi: Isolation, synthesis, and antifungal activity

The chemical structure determination of two phytoalexins from wasabi (Wasabia japonica, syn. Eutrema wasabi), a plant resistant to virulent isolates of the blackleg fungus [Leptosphaeria maculans (Desm.) Ces. et de Not., asexual stage Phoma lingam (Tode ex Fr.) Desm.], as well as their synthesis and antifungal activity towards isolates of P. lingam and P. wasabiae is reported.