You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 2,4-diphenyl-6-spiro[benzo[b]fluorene-11,9'-thioxanthene]-3'-yl-1,3,5-triazine is given. What is its corresponding molecular formula?
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C44H27N3S
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