You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[2-(9,9-dimethylfluoren-2-yl)phenyl]-7-[7-(9,9-dimethyl-7-phenylfluoren-2-yl)-9,9-dimethylfluoren-2-yl]-9,9-dimethylfluorene;2-[3-(9,9-dimethylfluoren-2-yl)phenyl]-7-[7-(9,9-dimethyl-7-phenylfluoren-2-yl)-9,9-dimethylfluoren-2-yl]-9,9-dimethylfluorene;2-[7-(9,9-dimethyl-7-phenylfluoren-2-yl)-9,9-dimethylfluoren-2-yl]-9,9-dimethyl-7-(2-phenylphenyl)fluorene;2-[7-(9,9-dimethyl-7-phenylfluoren-2-yl)-9,9-dimethylfluoren-2-yl]-9,9-dimethyl-7-(3-phenylphenyl)fluorene;2-[7-(9,9-dimethyl-7-phenylfluoren-2-yl)-9,9-dimethylfluoren-2-yl]-9,9-dimethyl-7-[3-phenyl-5-(4-phenylphenyl)phenyl]fluorene is the IUPAC name of a molecule. Please give its molecular formula.
user
C345H274
assistant