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 [(5S,9S)-2-[(2-methylpyrimidin-5-yl)methyl]-2-azaspiro[4.4]nonan-9-yl]-(oxazinan-2-yl)methanone into molecular formula.
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C19H28N4O2
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