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-methyl-5-[2-[5-methyl-2-(4-methylphenyl)-1,3-thiazol-4-yl]ethylsulfamoyl]benzoic acid by IUPAC nomenclature, provide its molecular formula.
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C21H22N2O4S2
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