You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [2-(ethoxycarbonylamino)-2-oxoethyl] (5S)-5-ethyl-4,5,6,7-tetrahydro-1-benzothiophene-2-carboxylate by IUPAC nomenclature, provide its molecular formula.
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C16H21NO5S
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