You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [1'-[(2-methylpropan-2-yl)oxycarbonyl]-4-oxospiro[3H-chromene-2,3'-pyrrolidine]-6-yl]oxidanium by IUPAC nomenclature, provide its molecular formula.
user
C17H22NO5+
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