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What is the molecular formula of the compound with this IUPAC name (3R,4R,6S)-5-phosphanyloxy-2-(phosphanyloxymethyl)-6-[(3S,4S,6S)-2-(phosphanyloxymethyl)-6-[(3S,4S)-2-(phosphanyloxymethyl)-4,5-diphosphoroso-6-prop-2-enoxyoxan-3-yl]oxy-4,5-diphosphorosooxan-3-yl]oxy-3-phosphorosooxan-4-ol ?
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C21H35O16P9
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