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What is the molecular formula of the molecule [(2S,3aS,6aS)-1-methyl-5-(5-methylpyrimidin-2-yl)-2,3,3a,4,6,6a-hexahydropyrrolo[2,3-c]pyrrol-2-yl]-(4-methylpiperazin-1-yl)methanone ?
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C18H28N6O
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