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What is the molecular formula of the molecule 2-(6',20'-dihydroxy-3-oxospiro[2-benzofuran-1,13'-2-oxapentacyclo[12.8.0.03,12.04,9.017,22]docosa-1(14),3(12),4(9),5,7,10,15,17(22),18,20-decaene]-5-yl)acetic acid ?
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C30H18O7
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