You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (5S)-6-(4-methoxybenzoyl)-7-(4-nitrophenyl)spiro[1,2,3,6,7,8-hexahydropyrrolizine-5,3'-1H-indole]-2'-one into its molecular formula.
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C28H25N3O5
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