You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [(2R)-1-anilino-1-oxopropan-2-yl] (3R)-1-(3-methylsulfanylphenyl)-5-oxopyrrolidine-3-carboxylate into its molecular formula.
user
C21H22N2O4S
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