You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 1-[1-(2-hydroxyethyl)-6,6-dioxo-2,3,4a,5,7,7a-hexahydrothieno[3,4-b]pyrazin-4-yl]-4-thiophen-2-ylbutan-1-one into molecular formula.
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C16H24N2O4S2
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