Guaianolide sesquiterpene lactones from Cichorium intybus (Asteraceae)

Abstract

Ten guaianolides, including three previously unreported natural products, were isolated from the aerial parts of Cichorium intybus (Asteraceae), more commonly known as chicory. Two of the new compounds (8 and 9) were analogues of lactupicrin and 11 beta ,13-dihydrolactupicrin, respectively, with the C-15 oxidized to the aldehyde state. The third new natural product, which we have called intybulide A (10), is an isomer of lactucin with the lactone closed to the C-8 oxygen rather than the C-6.