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What is the molecular formula of the compound with this IUPAC name 4-N-(9,9-dimethyl-4b,8a-dihydrofluoren-2-yl)-4-N'-(9-iodo-9-methylfluoren-2-yl)-4-N,4-N'-bis(4-phenylphenyl)-9,9'-spirobi[fluorene]-4,4'-diamine ?
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C78H57IN2
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