Abstract
3-Hydrazino-2,7,8,9-tetrahydro-1H-benzo [6',7']cyclohepta[1',2':4,5] pyrido[2,3-d] pyrimidin-1-one (5) was prepared in good yield by reaction of 3 or 4 with hydrazine hydrate under reflux. Reaction of compound 5 with different aldehydes in acetic acid gave the corresponding hydrazono derivatives 7. Cyclization of the latter compounds with bromine in acetic acid afforded a series of novel pentacyclic compounds namely,5,6,7,11-tetrahydro-15H-benzo[6 '',7 '']cyclohepta[1 '',2 '':4',5']pyrido[2', 3'-d][1,2,4] triazolo[4,3-alpha]pyrimidin-15-ones (11a-f). In addition, reaction of compound 5 with beta-diketones and alpha-diketone were investigated. The structures of the so formed compounds were confirmed by elemental and spectral analyses (H-1 NMR, C-13 NMR, IR and MS).