You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name methyl (3aS,8bS)-7-hydroxy-2-oxo-3a,8b-dihydro-3H-thieno[3,2-b][1]benzofuran-8-carboxylate into its molecular formula.
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C12H10O5S
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