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-(3,4-dihydro-2H-quinolin-1-ylsulfonyl)phenyl]-[(2R)-2-methylpiperazin-1-yl]methanone is given. What is its corresponding molecular formula?
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C21H25N3O3S
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