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What is the molecular formula of the molecule (3S,3aS,6S,6aR,9aR,9bS)-6-hydroxy-3-methyl-9-methylidene-6-[[(2R,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxymethyl]-3a,4,5,6a,7,8,9a,9b-octahydro-3H-azuleno[4,5-b]furan-2-one ?
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C21H32O9
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