You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 5-O-[3-[4-(2-butanoyloxyethyl)phenoxy]propyl] 3-O-methyl 2,6-dimethyl-4-(3-nitrophenyl)-3,4-dihydropyridine-3,5-dicarboxylate into molecular formula.
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C31H36N2O9
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