You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[1-[[2-(dimethylamino)pyrimidin-5-yl]methyl]-6,6-dioxo-2,3,4a,5,7,7a-hexahydrothieno[3,4-b]pyrazin-4-yl]-2-methylpropan-1-one by IUPAC nomenclature, provide its molecular formula.
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C17H27N5O3S
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