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system
What is the molecular formula of the molecule [(3aR,6aS)-3a-(hydroxymethyl)-3,4,6,6a-tetrahydro-1H-furo[3,4-c]pyrrol-5-yl]-(4-methyl-2-pyridin-3-ylpyrimidin-5-yl)methanone ?
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C18H20N4O3
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