Gravar-mail: 2,15-Dioxa-7,18,19,20,23-penta­aza­hepta­cyclo­[21.6.1.1(17,20).0(1,8).0(3,7).0(9,14).0(24,29)]hentriaconta-9,11,13,17(31),18,24,26,28-octaen-30-one