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 (2S,4S)-1-[(2-chlorophenyl)methyl]-4-[(4-methoxyphenyl)methylamino]-N-[2-(4-nitrophenyl)ethyl]pyrrolidine-2-carboxamide into molecular formula.
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C28H31ClN4O4
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