Lupinine (Lup)

Lupinine is a bitter tasting quinolizidine alkaloid present in Lupinus species (lupins), plants of the family Fabaceae.The characteristically bitter taste of lupin beans, attributable to the alkaloids which they contain,[1] renders them unsuitable for human and animal consumption. However, because lupin beans have potential nutritional value due to their high protein content, efforts have been made to reduce their alkaloid content, as well as to develop "sweet" varieties of Lupinus. One of the earliest isolations of lupinine, from Lupinus palmeri collected in Utah, USA, is that reported by Couch, who was able to obtain crystalline lupinine without the use of chromatographic techniques. There are numerous syntheses of lupinine in the literature. A recent synthesis, notable because it describes the preparation of all four stereoisomers of lupinine, and containing many references to earlier work in this field, was published by Ma and Ni.