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Under IUPAC nomenclature, a molecule named 2-[1-methyl-4-[4-[7-(1-methylpyrazol-4-yl)imidazo[1,2-c]pyrimidin-5-yl]pyrazol-1-yl]piperidin-4-yl]acetonitrile is given. What is its corresponding molecular formula?
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C21H23N9
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