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system
What is the molecular formula of the molecule (1S,5S,6R,13R)-7,7-dimethyl-8,12,20-trioxapentacyclo[11.8.0.02,11.04,9.014,19]henicosa-2,4(9),10,14(19),15,17-hexaene-5,6,17,18-tetrol ?
user
C20H20O7
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