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What is the molecular formula of the compound with this IUPAC name 1-[(3R)-3-[4-amino-3-[(E)-2-(2-chlorophenyl)ethenyl]pyrazolo[3,4-d]pyrimidin-1-yl]piperidin-1-yl]prop-2-en-1-one ?
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C21H21ClN6O
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