Lupinine is a quinolizidine alkaloid present in the genus Lupinus (colloquially referred to as lupins) of the flowering plant family Fabaceae.

[1] The scientific literature contains many reports on the isolation and synthesis of this compound as well as a vast number of studies on its biosynthesis from its natural precursor, lysine.

[4][5] The characteristically bitter taste of lupin beans, which come from the seeds of Lupinus plants, is attributable to the quinolizidine alkaloids which they contain, rendering them unsuitable for human and animal consumption unless handled properly.

[11] The neurotoxicity of lupinine has been known within veterinary medical circles for some time due to the use of lupins as a forage feed for grazing livestock since it has high protein content.

[13] Lupinine, in comparison to other quinolizidine alkaloids commonly found in lupins, such as lupanine and sparteine, shows a lower toxicity.

[4] This leads to the formation of an enzyme-sorption complex with the anionic portion of the acetylcholinesterase located on the active site of lupinine, namely the amine.

The aldehyde is then spontaneously cyclized into two tautmers which couple through an aldol type mechanism in which the allylic amine attacks the iminium, forming a dissymmetric dimeric intermediate which is then hydrated.

One 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.

[21] First, they employed asymmetric addition of the starting materials using a Lewis acid, followed by treatment with a reducing agent and a base.

[13] Studies of its insecticide activity have shown it to be effective against culicine mosquito larvae which are vectors for viruses, filarial worms, and avian malaria.