You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (5S)-5-(3-oxo-3-spiro[4,5-dihydrothieno[2,3-c]pyran-7,4'-piperidine]-1'-ylpropyl)imidazolidine-2,4-dione into molecular formula.
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C17H21N3O4S
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