You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance N-naphthalen-1-yl-5,5-diphenyl-N-(4-phenylphenyl)spiro[benzo[b][1]benzosiline-10,9'-xanthene]-3'-amine .
user
C59H41NOSi
assistant