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-[5-(dibenzofuran-3-ylsulfamoyl)-1,3,4-thiadiazol-2-yl]benzamide is given. What is its corresponding molecular formula?
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C21H12Cl2N4O4S2
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