You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-(4-dibenzothiophen-4-ylphenyl)-N-spiro[fluorene-9,9'-thioxanthene]-3-ylspiro[fluorene-9,9'-xanthene]-3-amine by IUPAC nomenclature, provide its molecular formula.
user
C68H41NOS2
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