You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 3-ethyl-2-oxo-N-[(1S)-1-pyridin-3-yl-2-thiophen-3-ylethyl]-1,3-benzoxazole-6-sulfonamide is given. What is its corresponding molecular formula?
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C20H19N3O4S2
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