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system
What is the molecular formula of the molecule (2S,3S,4R,5S,6S)-2-[5,7-dihydroxy-2-(3,4,5-trihydroxyphenyl)chromenylium-3-yl]oxy-6-(hydroxymethyl)oxane-3,4,5-triol ?
user
C21H21O12+
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