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What is the molecular formula of the compound with this IUPAC name (2R)-2-[[2-(7,7a-dihydro-4aH-pyrrolo[2,3-d]pyrimidin-5-yl)-5-fluoropyrimidin-4-yl]-methylamino]-3-methyl-N-(2,2,2-trifluoroethyl)butanamide ?
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C18H21F4N7O
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