New Depsides From Erioderma Lichens

Abstract

A chemosyndrome of para- depsides based on methyl 4-O-demethylbarbatate (3) has been detected in Erioderma lichens and the structures of the metabolites have been established by unambiguous syntheses. New depsides include methyl 5-chloro-4-O-demethylbarbatate (4), methyl eriodermate (5), methyl 2'-0-methyleriodermate (6), methyl 2-O-methyleriodermate (7), methyl 4-O-methyleriodermate (8) and methyl 2,2'-di-O-methyleriodermate (9).