You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-phenyl-4-(4-phenylphenyl)-6-(6'-pyridin-4-ylspiro[fluorene-9,9'-xanthene]-3'-yl)-1,3,5-triazine into molecular formula.
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C51H32N4O
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