Floramultine is an isoquinoline alkaloid that has been found in C. speciosum.1 It inhibits butyrylcholinesterase (BChE) and acetylcholinesterase (AChE; Kis = 23.44 and 151.3 µM, respectively).
1.Basova, N.E., Rozengart, E.V., and Suvorov, A.A.Cholinergic activity of isoquinoline alkaloids from the showy autumn crocus (Colchicum speciosum Stev.)Dokl. Biochem. Biophys.40627-31(2006)