[aR,(-)]-5,5',6,6',8,8'-Hexahydroxy-2-hydroxymethyl-2'-methyl-9,9'-bi[4H-naphtho[2,3-b]pyran]-4,4'-dione

ChEBI: Ustilaginoidin B is a binaphthopyran resulting from the formal oxidative coupling at positions 9 of molecules of 5,6,8-trihydroxy-2-methyl-4H-benzo[g]chromen-4-one and 5,6,8-trihydroxy-2-(hydroxymethyl)-4H-benzo[g]chromen-4-one. It has a role as a mycotoxin. It is a benzochromenone, a binaphthopyran and a naphtho-gamma-pyrone.