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-dibenzothiophen-3-yl-4-phenyl-6-(3-spiro[fluorene-9,9'-xanthene]-4'-ylphenyl)-1,3,5-triazine into molecular formula.
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C52H31N3OS
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