CHEMOTYPES OF 2 PYRROLIZIDINE ALKALOID-CONTAINING SENECIO SPECIES

Evaluation of the pyrrolizidine alkaloids (PAs) of more than 100 populations of Senecio jacobaea and of ca 25 populations of S. erucifolius from different geographic locations revealed the existence of different chemotypes. Two chemotypes were established within each species. They are for S. jacobaea, (a) jacobine chemotype' with jacobine and its derivatives as major PAs, representing the well known 'classical' PA pattern of this species. (b) 'erucifoline chemotype', with erucifoline and O-acetylerucifoline as dominating PAs, and for S. erucifolius, (a) 'erucifoline chemotype', erucifoline and O-acetylerucifoline as major PAs. (b) 'cruciflorine chemotype', with eruciflorine (21-hydroxyintegerrimine) as dominating PA. Eruciflorine was identified as a novel PA. Its structure was elucidated by means of NMR and mass spectrometry. Individual populations representing the different chemotypes within the respective species are indistinguishable from their morphological characters.