You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 2-(furan-2-yl)-6-[(6-pyrrolidin-1-ylpyridin-3-yl)methyl]-7,8-dihydro-5H-pyrido[4,3-d]pyrimidine into its molecular formula.
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C21H23N5O
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