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What is the molecular formula of the molecule identified by (E)-4-[(1S,12S,14S,15E,16R)-15-ethylidene-16-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy-3,17-diazapentacyclo[12.3.1.02,10.04,9.012,17]octadeca-2(10),4,6,8-tetraen-13-yl]but-3-en-2-one ?
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C28H34N2O7
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