Norbadione A is a pigment found in the bay bolete mushroom (Boletus badius).

[1] The molecule has also been reported as a potassium salt from the mushrooms Pisolithus tinctorius (horse dung fungus)[2] and Chalciporus piperatus.

It selectively complexes caesium cations (Cs+),[5] with an efficiency comparable to that of some calixarenes or crown ethers.

[7] A diverse array of synthetic derivatives of norbadione A has been created to explore the effect of structure on antioxidant properties and cytotoxicity.

There is a pH-dependent Z to E isomer switch that occurs in both pulvinate moieties,[10] which yields four stereoisomeric forms (E/E, E/Z, Z/Z, Z/E).