What is "amavadin"

n. (context chemistry English) A complex anion, containing vanadium, found in some species of ''Amanita'' mushrooms

Amavadin is a vanadium-containing anion found in three species of poisonous Amanita mushrooms: A. muscaria, A. regalis, and A. velatipes. Amavadin was first isolated and identified in 1972 by Kneifel and Bayer. This anion, which appears as a blue solution, is an eight-coordinate vanadium complex. A Ca cation is often used to crystallize amavadin to obtain a good quality X-ray diffraction. Oxidized amavadin can be isolated as its PPh salt. The oxidized form contains vanadium(V), which can be used to obtain an NMR spectrum.