XVI International Botanical Congess
Occurrence of a wide variety of alkaloids has been reported for the largest convolvulaceous genus Ipomoea (650 species). The first pyrrolizidine alkaloids (PA) were isolated from I. hederifolia, belonging to the subg. Quamoclit, sect. Mina. In our study we report the occurrence of a unique type of PA in five species of this section. We suppose that this occurrence might be a chemosystematic marker of this taxon since we could not detect such compounds in numerous species of this genus outside the sect. Mina or of other convolvulaceous genera.