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What is the molecular formula of the compound with this IUPAC name methyl (2R,3R,4S,5R,6S)-4-(2,2-dimethoxyethyl)-5-ethenyl-2-methoxy-6-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyoxane-3-carboxylate ?
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C20H34O12
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