You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 2-[(2S)-2',4-dioxo-3-phenylspiro[1,3-thiazolidine-2,3'-indole]-1'-yl]-N-(4-propan-2-ylphenyl)acetamide into molecular formula.
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C27H25N3O3S
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