27556-19-0 Spiro(2,5-methano-7H-oxireno(3,4)cyclopent(1,2-d)oxepin-7,2'-oxiran)-3(2ah)-one, 1a-beta,1b,5a,6,6a,7a-beta-hexahydro-1b-alpha,6-beta-dihydroxy-8a-isopropenyl-6a-alpha-methyl-, monoacetate Tutin monoacetate