5,5',7,7'-tetramethyl-20-oxa-7,7'-diazaspiro[heptacyclo[13.6.1.1~5,9~.0~1,12~.0~4,11~.0~14,16~.0~16,21~]tricosane-19,12'-hexacyclo[9.6.2.0~1,8~.0~5,17~.0~9,14~.0~14,18~]nonadecane]-4(11),12-diene (non-preferred name)