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system
Provide the molecular formula for the IUPAC named substance 7',19'-dihydroxyspiro[2-benzofuran-3,13'-2-oxapentacyclo[12.8.0.03,12.04,9.017,22]docosa-1(14),3(12),4(9),5,10,15,17(22),20-octaene]-1-one .
user
C28H20O5
assistant