You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-O-methyl 4-O-[(2R,3R,4S,5S,6R)-3,4,5-tri(propanoyloxy)-6-(trityloxymethyl)oxan-2-yl] (E)-but-2-enedioate by IUPAC nomenclature, provide its molecular formula.
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C39H42O12
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