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-[(2-ethoxy-5-methylphenyl)sulfonylamino]phenyl]-N-(1-hydroxy-2-methylpropan-2-yl)acetamide is given. What is its corresponding molecular formula?
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C21H28N2O5S
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