Three New Aliphatic Acids from Lichens of Genus Parmelia (Subgenus Xanthoparmelia)

Abstract

The aliphatic acids, constipatic acid [2-(14'-hydroxypentadecyl)-4-methyl-5-oxo-2,5-dihydrofuran- 3-carboxylic acid], protoconstipatic acid [2-(14'-hydroxypentadecyl)-4-methylene-5-oxotetrahydro- furan-3-carboxylic acid] and dehydroconstipatic acid [4-methy1-5-oxo-2-(14'-oxopentadecy1)-2,5- dihydrofuran-3-carboxylic acid], have been identified as constituents of various Xanthoparmelia lichens from Australia.