A Synthesis of the Lichen Dibenzofuran Pannaric Acid 6-Methyl Ester

Abstract

A total synthesis of pannaric acid 6-methyl ester (3,9-dihydroxy-6-methoxycarbonyl-1,7-dimethyldibenzofuran-2-carboxylic acid) (2) has been achieved by a biomimetic -type approach with palladium(II) acetate in the key cyclization step. This acid (2) was shown to be identical with the major metabolite of the lichen Leproloma vouauxii.