You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[4-[2-[4-[di(phenanthren-9-yl)amino]phenyl]ethenyl]phenyl]-N-phenanthren-9-ylphenanthren-9-amine into molecular formula.
user
C70H46N2
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