You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-(furan-2-yl)-8-[[4-(3-methoxyphenyl)piperazin-1-yl]methyl]-[1,2,4]triazolo[1,5-c]pyrimidin-5-amine by IUPAC nomenclature, provide its molecular formula.
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C21H23N7O2
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