Benzofuran derivatives from enceliopsis argophylla

From the composite Enceliopsis argophylla several new benzofuran derivatives were isolated. The unusual structure of the skeleton comprises an isopropylidene group at C-2 and a keto function at C-3 of the furan ring. An organ specific analysis by HPLC showed the compounds being present in leaves, peduncles, bracts, ray and disc flowers. The absolute amounts, however, differed greatly being highest in leaves and bracts.