Sesquiterpene lactones from brazilian Tithonia diversifolia

Abstract Aerial parts of Tithonia diversifolia collected in Sao Paulo State afforded two new heliangolides in addition to the heliangolides tagitinin F and 1,2-epoxytagitinin C, one known guaianolide and the flavone hispidulin. Structures were established by spectroscopic studies. © 1997 Elsevier Science Ltd. All rights reserved