Abstracto
- The investigation of 17 Senecio species afforded in addition to 14 known pyrrolizidine alkaloids 20 new ones, including some compounds of a novel type with an additional lactone moiety. Furthermore seven known and 11 new furoeremophilanes, two known and a new eremophilone, a further shikimic acid derivative and an acetylenic compound, most likely formed by intramolecular Diels-Alder reaction were isolated. The structures were elucidated by spectroscopic methods, especially high field 1H and 13C NMR and NOE difference spectroscopy. The configuration of the seneremophilondiol esters has been corrected.