You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (4R,7R)-6,8-dihydroxy-7,10a-dimethyl-2-oxo-4-propan-2-yl-4,4a,5,6,6a,8,9,10-octahydrobenzo[f]isochromene-7-carbaldehyde;ethane into molecular formula.
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C21H34O5
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