First total synthesis of cyrmenin B1.

A short and efficient synthesis of cyrmenin B(1), an antifungal metabolite of myxobacteria Cystobacter armeniaca and Archangium gephyra, is described. The crucial steps of the synthesis included the formation of the dehydroalanine moiety from the corresponding serine acetate and the formation of the beta-methoxyacrylate system via trimethylsilyldiazomethane methylation of the corresponding beta-hydroxy enamide.