You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (3,4-dichlorophenyl)-(6,6-dioxo-2,3,4a,5,7,7a-hexahydrothieno[3,4-b][1,4]oxazin-4-yl)methanone into its molecular formula.
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C13H13Cl2NO4S
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