You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (3S)-5-methoxy-N-[(3-methoxyphenyl)methyl]-1-methyl-2-oxospiro[indole-3,3'-pyrrolidine]-1'-carboxamide into its molecular formula.
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C22H25N3O4
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