You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-[4-(2-dibenzothiophen-1-ylphenyl)phenyl]-N-(9,9-dimethylfluoren-2-yl)-3',7'-dimethylspiro[1-azapentacyclo[10.7.1.02,7.08,20.014,19]icosa-2,4,6,8,10,12(20),14,16,18-nonaene-13,9'-bicyclo[3.3.1]nonane]-9-amine by IUPAC nomenclature, provide its molecular formula.
user
C68H56N2S
assistant