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 [2-(3,4-dichloroanilino)-2-oxoethyl] (3R)-1-[(2-methylbenzoyl)amino]-5-oxopyrrolidine-3-carboxylate into molecular formula.
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C21H19Cl2N3O5
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