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What is the molecular formula of the molecule 4-(hydroxymethyl)-3'-propan-2-yl-1-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]peroxyspiro[4a,5,6,7a-tetrahydro-1H-cyclopenta[c]pyran-7,5'-furan]-2'-one ?
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C21H30O11
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