2,2',7,7'-tetraphenyl-9,9'-spirobi[fluorene]

N,N',N'',N'''-Tetra(1-naphthyl)-N,N',N'',N'''-tetraphenyl-9,9'-spirobi[fluorene]-2,2',7,7'-tetramine

2,2',7,7'-Tetramethoxy-9,9'-spirobi[fluorene]

2,2',7,7'-tetraiodo-9,9'-spirobi[fluorene]

2,2',7,7'-tetrabromo-9,9'-spirobi[fluorene]

2,2',7,7'-tetranitro-9,9'-spirobi[fluorene]

2,2',7,7'-Tetraformyl-9,9'-spirobifluorene