sentences:  It is the predominant alkaloid in "Lupinus mutabilis", and is thought to chelate the bivalent cations calcium and magnesium.It is not FDA approved for human use as an antiarrhythmic agent, and it is not included in the Vaughan Williams classification of antiarrhythmic drugs.It is also used as a chiral ligand in organic chemistry, especially in syntheses involving organolithium reagents.