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 [6-[3-(2-methylpropyl)-1,2-oxazole-5-carbonyl]-3,6-diazabicyclo[3.2.2]nonan-3-yl]-pyridin-4-ylmethanone into molecular formula.
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C21H26N4O3
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