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What is the molecular formula of the molecule (2S,3S)-2-(3,4-dihydroxyphenyl)-3,5-dihydroxy-7-[(2S,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxy-2,3-dihydrochromen-4-one ?
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C21H22O11
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