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What is the molecular formula of the molecule identified by (11Z,14Z,17Z,20Z,23Z)-N-[1-[5-[3,4-dihydroxy-6-(hydroxymethyl)-5-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyoxan-2-yl]oxy-3,4-dihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy-3-hydroxynonan-2-yl]hexacosa-11,14,17,20,23-pentaenamide ?
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C53H91NO18
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