4,8,12,16,20-Pentaazatricosanedinitrile,8,16-bis[3-[bis(2-cyanoethyl)amino]propyl]-4,20-bis(2-cyanoethyl)-12-[2-(2,5-dihydro-2,5-dioxo-3,4-diphenyl-1H-pyrrol-1-yl)ethyl]-