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 ethyl 1-[(2S)-4-methoxy-1-(4-methoxy-2-nitroanilino)-1,4-dioxobutan-2-yl]piperidine-4-carboxylate into molecular formula.
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C20H27N3O8
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