You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2R)-1-[2-oxo-2-[[(3S)-1-phenylpyrrolidin-3-yl]methylamino]ethyl]pyrrolidine-2-carboxylic acid into its molecular formula.
user
C18H25N3O3
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