Synonyms: (9R)-2-Oxo-8,8-dimethyl-9,10-dihydro-2H,8H-benzo[1,2-b:3,4-b']dipyran-9α,10α-diol 9,10-bis[(Z)-2-methyl-2-butenoate];[(9R,10R)-9,10-Dihydro-8,8-dimethyl-2-oxo-2H,8H-benzo[1,2-b:3,4-b']dipyran-9,10-diyl]di[(Z)-2-methyl-2-butenoate];9,10-Dihydro-8,8-dimethyl-9α,10α-bis[(Z)-1-oxo-2-methyl-2-butenyloxy]-2H,8H-benzo[1,2-b:3,4-b']dipyran-2-one