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Can you give the molecular formula of the molecule (1R,3R)-3-[[3-bromo-1-(4-oxopyrido[1,2-a]pyrimidin-7-yl)pyrazolo[3,4-d]pyrimidin-6-yl]amino]-N,1-dimethylcyclopentane-1-carboxamide ?
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C21H21BrN8O2
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