You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 1'-[(3R)-3-(5-methylfuran-2-yl)butyl]spiro[1,4-dihydroquinoxaline-3,4'-piperidine]-2-one into molecular formula.
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C21H27N3O2
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