You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule [2,7-dihydroxy-3-(5-hydroxyhept-1-enyl)-6,6-dimethyl-2,4a,7,8-tetrahydro-1aH-oxireno[2,3-e]chromen-4-yl]methyl acetate into molecular formula.
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C21H32O7
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