An erythrina alkaloid with formula C18H21NO3 isolated from several erythrina plant species. It is a competitive antagonist of nicotinic acetylcholine receptors and exhibits antiparasitic and insecticidal activities. ChEBI: Erysodine is an erythrina alkaloid with formula C18H21NO3 isolated from several erythrina plant species. It is a competitive antagonist of nicotinic acetylcholine receptors and exhibits antiparasitic and insecticidal activities. It has a role as a nicotinic antagonist, a phytogenic insecticide and an antiparasitic agent. It is an aromatic ether, an Erythrina alkaloid, an organic heterotetracyclic compound, a diether and a member of phenols.