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What is the molecular formula of the molecule 14-ethylidene-4,15-bis[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy]-2,10,16,20-tetraoxatetracyclo[21.2.2.13,7.013,18]octacosa-1(25),3,5,7(28),17,23,26-heptaene-11,19-dione ?
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C38H46O18
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