You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 8-(3-phenylspiro[12H-indeno[1,2-a]carbazole-7,9'-fluorene]-3'-yl)spiro[11-thia-15-azaheptacyclo[14.11.0.02,14.04,12.05,10.017,25.018,23]heptacosa-1(16),2,4(12),5(10),8,13,17(25),18,20,22,26-undecaene-24,9'-fluorene] into molecular formula.
user
C74H44N2S
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