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system
Provide the molecular formula for the IUPAC named substance (14Z,17R,18R)-18-[(2R)-4-(2,6-dihydroxyphenyl)-4-oxobutan-2-yl]-13,15-dihydroxy-14-(1-hydroxyethylidene)-17-methyl-8-oxapentacyclo[10.6.2.02,7.09,19.016,20]icosa-1,4,6,9,12,15,19-heptaene-3,11-dione .
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C32H26O9
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