A series of new derivatives of 7,7'-(1,4-phenylene)bis [(5-substitutedphenyl-1,3,4-oxadiazol-2-yl)-amino(7,8dihydropyrazino[2,3-e][1,3]oxazepine-5,9-dione)] 3a-d and 7,7'-(1,4-phenylene)bis[(5-substitutedphenyl-1,3,4-oxadiazol-2yl)-amino(7,8-dihydro-5H-pyrazino[2,3-e][1,3]diazepine-5,9(6H)-dione)] 4a-d have been prepared by the cycloaddition reaction of 2,3-pyrazinedicarboxylic anhydride (and/or 2...