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 4-[[1-(3-chlorophenyl)-2,5-dioxopyrrolidin-3-yl]-[(4-sulfamoylphenyl)methyl]amino]-4-oxobutanoic acid is given. What is its corresponding molecular formula?
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C21H20ClN3O7S
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