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 7-bromo-2-[4-methoxy-3-(4-methylpiperazin-1-yl)phenyl]sulfonyl-3,4-dihydro-1H-isoquinoline is given. What is its corresponding molecular formula?
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C21H26BrN3O3S
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