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system
Provide the molecular formula for the IUPAC named substance (15R,19R)-17-[4-(azepane-1-carbonyl)phenyl]-1,8-dibromo-17-azapentacyclo[6.6.5.02,7.09,14.015,19]nonadeca-2,4,6,9,11,13-hexaene-16,18-dione .
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C31H26Br2N2O3
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