You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [1,3-diacetyloxy-9,10-dihydroxy-7,8-dimethyl-7-(3-methylidenepent-4-enyl)-1,3,5,6,6a,8,9,10-octahydrobenzo[d][2]benzofuran-5-yl] butanoate into its molecular formula.
user
C28H40O9
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