苯并-12-冠-4 、
1,3,4,6-tetrakis(hydroxymethyl)tetrahydro-3a,6a-diphenylimidazo<4,5-d>imidazole-2,5(1H,3H)-dione 在
polyphosphoric acid 作用下,
反应 0.5h,
以36%的产率得到28b,28c-diphenyl-2,3,5,6,8,9,12,14,17,18,20,21,23,24,27,28b,28c,29-octadecahydro-1,4,7,10,16,19,22,25-octaoxa-12a,13a,27a,28a-tetraazacyclododeca[1',2':4,5]benzo[1,2-f]cyclododeca[1'',2'':4',5']benzo[1',2':5,6]azuleno[2,1,8-ija]azulene-13,28-dione