2,2'-(Piperazin-1,4-diyl)bis(6,7-dimethoxyquinazolin-4-amine); 2,2'-(1,4-Piperazinediyl)bis[6,7-dimethoxy-4-quinazolinamine];2-[4-(4-Amino-6,7-dimethoxyquinazolin-2-yl)piperazin-1-yl]-6,7-dimethoxyquinazolin-4-amine;