The synthesis of 2, 3, 5, 6-tetrahydro-1H, 4H, 11cH-3a, 6a, 11b-triazabenz [de] anthracene (5) is described. X-ray crystal structure deteminations on hexahydro-1H, 4H, 7H, 9bH-3a, 6a, 9a-triazaphenalene (1) and its benzoanalogue (5) show them to adopt differing conformations; the reasons for this are discussed.