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Under IUPAC nomenclature, a molecule named 2-[4-(1,3-benzothiazole-2-carbonyl)-5-bromo-7-fluoro-2,3-dihydro-1H-pyrrolo[1,2-a]indol-3-yl]acetic acid is given. What is its corresponding molecular formula?
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C21H14BrFN2O3S
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