Chemotaxonomic value of pyrrolizidine alkaloids in southern Brazil Senecio (Senecioneae: Asteraceae)

Pyrrolizidine alkaloids (PAs) were characterized by GC-MS in inflorescences of 14 Senecio species (S. brasiliensis, S. conyzifolius, S. heterotrichius, S. oleosus, S. oxyphyllus, S. riograndensis, S. selloi, S. bonariensis, S. grossidens, S. icoglossus, S. juergensii, S. pulcher, S. ceratophylloides and S. crassiflorus) from southern Brazil, belonging to three taxonomic sections of the genus. The 1,2-saturated macrocycle diesters (such as platyphylline or rosmarinine), 1,2-saturated or unsaturated triangularine-like alkaloids such as senecioylplatinecine and senecioylretronecine were characteristic for the section Hualtatini. The section Corymbosi has, as characteristic PAs, 1,2-unsaturated 12-membered macrocyclic diesters (such as senecionine), while the section Suffrutecius is ambiguous in relation to the PA profile. The data indicate that the PA patterns are mostly in good agreement with morphological data for the sections Corymbosi and Hualtatini and that they can be useful chemotaxonomic markers at the infrageneric level. (C) 2003 Elsevier Science Ltd. All rights reserved.