You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[(E)-2-naphthalen-2-yl-3-(9,9'-spirobi[fluorene]-2-yl)prop-1-enyl]-9-phenylcarbazole is the IUPAC name of a molecule. Please give its molecular formula.
user
C56H37N
assistant