You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [(3S)-1-(benzenesulfonyl)piperidin-3-yl]-[(2S)-5-bromo-2-methyl-2,3-dihydroindol-1-yl]methanone into its molecular formula.
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C21H23BrN2O3S
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