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 (3aS,6R,11aS,11bR)-6-(3-ethoxy-4-hydroxyphenyl)-9-methyl-2-(3-nitrophenyl)-3a,4,6,11,11a,11b-hexahydronaphtho[6,7-e]isoindole-1,3,7,10-tetrone into molecular formula.
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C31H26N2O8
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