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What is the molecular formula of the compound with this IUPAC name methyl 12-methyl-17-oxo-4-prop-1-en-2-yl-11,16,18,19-tetraoxapentacyclo[12.2.2.16,9.01,15.010,12]nonadeca-6,8-diene-7-carboxylate ?
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C21H24O7
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