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What is the molecular formula of the molecule identified by 3-[4-[3-[2-[(3',6'-dihydroxy-3-oxospiro[2-benzofuran-1,9'-xanthene]-5-yl)carbamothioylamino]ethoxy]propanoylsulfanyl]phenyl]propanoic acid ?
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C35H30N2O9S2
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