3,3'''',6,6''''-Tetra-tert-butyl-6',6'''-bis(3,6-di-tert-butyl-9H-carbazol-9-yl)-9''-(4-(3,3'',6,6''-tetra-tert-butyl-9'H-[9,3':6',9''-tercarbazol]-9'-yl)phenyl)-9''H-9,3':9',3'':6'',9''':3''',9''''-quinquecarbazole