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system
Name the molecular formula for the molecule established as 1,6,9,17,19-pentahydroxy-5,13-bis(4-hydroxyphenyl)-4,12,14-trioxapentacyclo[11.8.0.02,11.03,8.015,20]henicosa-2(11),3(8),5,9,15,17,19-heptaene-7,21-dione using the IUPAC nomenclature.
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C30H18O12
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