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What is the molecular formula of the compound with this IUPAC name 6-[2-chloro-4-(6-methylpyrazin-2-yl)phenyl]-2-(ethylamino)-8-[2-(3-oxopiperazin-1-yl)ethyl]pyrido[2,3-d]pyrimidin-7-one ?
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C26H27ClN8O2
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