Alkaloids of the genus Poecilanthe (Leguminosae: Papilionoideae)

Abstract The presence of alkaloids in the genus Poecilanthe is reported for the first time. Epilupinine, 4β-hydroxyepilupinine, dihydrolusitanine, dihydroammodendrine, lusitanine, N -methylcytisine, cytisine, lupanine, N -formylcytisine, anagyrine, baptifoline, camoensidine and four novel alkaloids were found as major alkaloids in leaves and seeds of the genus Poecilanthe . Tashiromine, acetylepilupinine, ammodendrine, α-isolupanine, 5,6-dehydrolupanine, aphyllidine, aphylline, thermopsine, epibaptifoline, rhombifoline, tinctorine, 11-allylcytisine, acetylbaptifoline and at least seven unknown compounds were found as minor alkaloids in the extracts studied. The co-occurence of different types of quinolizidine (bicyclic lupinine-type, lupanine-type, leontidine-type and α-pyridone-type) and bipiperidyl alkaloids appears to be a good chemotaxonomic marker for the genus. The presence of alkaloids in Poecilanthe suggests a relationship of this genus with the tribes Sophoreae or Brongniartieae rather than with the Dalbergieae. The alkaloidal data indicate that the genus can be divided into two phytochemical groups: one group of species accumulating mainly α-pyridone alkaloids and a second group accumulating bicyclic quinolizidine alkaloids, with α-pyridones being totally absent.