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 2,4-dichloro-N-(3-cyano-4,5,6,7-tetrahydro-1-benzothiophen-2-yl)-5-(4-oxopiperidin-1-yl)sulfonylbenzamide is given. What is its corresponding molecular formula?
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C21H19Cl2N3O4S2
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