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 5-[4-ethoxy-5-(7-methyl-9,9-dioctylfluoren-2-yl)thiophen-2-yl]-8-(4-ethoxy-5-methylthiophen-2-yl)-2,3-diphenylquinoxaline into molecular formula.
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C63H70N2O2S2
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