Synthesis and Biological Evaluation of Novel Tetrahydro-1,2,4-triazines Incorporating Triazene and Tetraazene Moieties

Diazotization of the hydrazone (2), derived from 6-Acetyl-2,4-diphenyl-tetrahydro-1,2,4-triazine (1), gave the corresponding 1-chlorotriaz-2-enylidene derivative 3. Coupling of 3 with resorcinol and 2-naphthol afforded the triazenes 4 and 5. The synthesis of tetrahydro-1,2,4-triazine incorporating triazene and piperidine or piperazine moieties has been achieved by coupling of 3 with the respective amine. Coupling of 3 with aromatic amines and polyhydroxy amines gave the corresponding tetraazenes. Whereas, coupling with the hydrazone 2 afforded pentaazene. In addition, the coupling of aryl diazonium salts with the hydrazone 2 was investigated.