New Hopane Triterpenoids From Lichens in the Family Physiaceae

Abstract

Three new hopane triterpenes have been isolated from lichens of the family Physciaceae. Two of the triterpenes, 22-hydroxyhopan-6-one (2) and 6 α-acetoxyhopan-22-ol (1b), have been characterized previously but their natural occurrence is reported for the first time, while a new triterpene acid [ aipolic acid (1c)], was isolated and characterized as the corresponding methyl ester. One- and two-dimensional ¹H-¹H and ¹³C^-lH correlated n.m.r. studies have revealed methyl aipolate to be methyl 6#945;-acetoxy-22-hydroxyhopan-25-oate (1d).