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 3-(6-bromo-1,3,4,5-tetrahydropyrido[4,3-b]indole-2-carbonyl)-N-propan-2-ylbenzenesulfonamide is given. What is its corresponding molecular formula?
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C21H22BrN3O3S
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