2β-(2,6-dimethoxy-4-methylbenzoyl)-7-oxabicyclo<2.2.1>heptane-3β-carboxylic acid

6,8a-dibromo-5a,5,6,7,8,8a-hexahydro-1-hydroxy-8-methoxycarbonyl-3-methyl-7-oxoxanthone

8aβ-bromo-5a,5,6,7,8,8a-hexahydro-1,7α-dihydroxy-8α-methoxycarbonyl-3-methylxanthone

1-hydroxy-8aβ-bromo-3-methyl-8α-methoxycarbonyl-7-oxo-5a,5,6,7,8,8a-hexahydroxanthone