(9,9'-Bi-4H-naphtho(2,3-b)pyran)-4,4'-dione,2,2',3,3'-tetrahydro-5,5',6,6',8,8'-hexahydroxy-2,2',3,3'-tetramethyl
(9,9'-bi-4h-naphtho(2,3-b)pyran)-4,4'-dione,2,2',3,3'-tetrahydro-5,5',6,6',8,8'-hexahydroxy-2,2',3,3'-tetramethyl