You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [2-(2-ethylanilino)-2-oxoethyl] (3R)-1-[(3,4-dichlorobenzoyl)amino]-5-oxopyrrolidine-3-carboxylate into its molecular formula.
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C22H21Cl2N3O5
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