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 3'-[(3-tert-butyl-1,2,4-oxadiazol-5-yl)methyl]spiro[1,3-dihydroindene-2,5'-imidazolidine]-2',4'-dione into molecular formula.
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C18H20N4O3
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