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Translate the chemical IUPAC name 4,11-dibromo-17,19-bis(9,9'-spirobi[fluorene]-2-yl)-18-thia-15,21-diazapentacyclo[12.7.0.02,7.08,13.016,20]henicosa-1(21),2(7),3,5,8(13),9,11,14,16,19-decaene into its molecular formula.
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C68H36Br2N2S
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