Neue sesquiterpenlactone und andere inhaltsstoffe aus vertretern der Eupatorium-gruppe

The investigation of twelve further species of the Eupatorium complex affords four new germacrolides and seven guaianolides together with new thymol and p-hydroxyacetophenone derivatives. The structures of these compounds have been elucidated by spectroscopic methods. Chemotaxonomic aspects of these findings are briefly discussed.     

Neue eremophilan-derivate aus Lopholaena-arten

The genus Lopholaena contains several eremophilane derivatives. The structures of four new furanoeremophilanes and one eremophilone derivative were elucidated using spectroscopic methods. The chemical relationship of Lopholaena to other genera is discussed.     

Neue labdan-derivate aus Chrysothamnus nauseusus

The South American Chrysothamnus species afforded in addition to known compounds six new labdanetype acids, a bisabolene and a germacrene derivative as well as a new flavanone. The structures were elucidated by spectroscopic methods.     

Neue germacren-derivate aus Senecio-arten

From the succulent Senecio species, S. cylindricus, eight new germacrene derivatives were isolated, while S. erosus afforded two new furanoeremophilones. Six further species only contain known compounds. The chemotaxonomic importance of these findings are briefly discussed.     

Neue diterpene aus Gnaphalium-arten

The investigation of Gnaphalium undulatum afforded two new labdane derivatives, one having a new carbon skeleton, and a new flavonol. Furthermore, an unknown diterpene lactose is present; its structure, however, could not be elucidated. The only American species investigated contains the trans-isomer of the precursor of the acetylenic chloroenol ether, which is widespread in Gnaphalium and in related genera. The chemotaxonomic situation is discussed briefly.     

Neue cadinan-derivate aus Heterotheca subaxillaris

The investigation of some Heterotheca species afforded three new cadinane angelicates, in addition to several known compounds. The structures are elucidated by spectroscopic methods. The chemotaxonomic situation is discussed briefly.