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Provide the molecular formula for the IUPAC named substance 2-bromo-N-[4-chloro-3-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-3-yl)phenyl]benzenesulfonamide .
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C19H18BrClN4O2S
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