You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (3S)-N-[3-(4-methoxyphenyl)propyl]-5-oxo-1-(pyridin-3-ylmethyl)pyrrolidine-3-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C21H25N3O3
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