New vernolepin derivatives from Vernonia glabra and glaucolides from Vernonia scorpioides

Abstract The aerial parts of VERNONIA GLABRA afforded in addition to vernolepin, vernodalin and vernomenin, four further sesquiterpene lactones derived from vernolepin (1), two germacranolides and together with vernodalol the corresponding lactone 9. From VERNONIA SCORPIOIDES two further glaucolides (14) and (15) were isolated. The structure of the tiglate (16) is revised. The structure were elucidated by spectroscopic methods.