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What is the molecular formula of the molecule 11-(9,9'-spirobi[fluorene]-4'-yl)-1-azapentacyclo[11.7.1.03,8.09,21.014,19]henicosa-3,5,7,9,11,13(21),14,16,18-nonaene-2,20-dione ?
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C45H25NO2
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