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system
For the molecule named 2-[5'-(4,6-diphenyl-1,3,5-triazin-2-yl)spiro[1-azapentacyclo[10.7.1.02,7.08,20.014,19]icosa-2,4,6,8(20),9,11,14,16,18-nonaene-13,9'-fluorene]-3'-yl]-4-(9-phenylcarbazol-3-yl)-[1]benzofuro[3,2-d]pyrimidine by IUPAC nomenclature, provide its molecular formula.
user
C74H43N7O
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