You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2,6-bis[2,7-bis(3,5-dimethylphenyl)carbazol-9-yl]-3-[2-isocyano-6-(trifluoromethyl)phenyl]benzonitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C71H53F3N4
assistant