2-O-Methylobtusatic Acid, a New Depside from the Lichen Xanthoparmelia tusconensis

Abstract

The depside, 2-O-methylobtusatic acid [4-(2',4'-dimethoxy-3',6'-dimethylbenzoyloxy)-2-hydroxy-6-methylbenzoic acid] has been prepared by unambiguous synthesis and shown to co-occur with usnic acid and diffractaic acid in the lichen Xanthoparmelia tusconensis.