SYNTHESIS OF NOVEL SUBSTITUTED [1,2,4]TRIAZOLO[1,5-a]PYRIDINES AND THEIR RELATED PYRANO[2,3-d]IMIDAZOLE DERIVATIVS
Wahid M. Basyouni
Pesticide Chemistry Dept., National Research Center, Dokki, Cairo, Egypt
Synthesis of the diaminopyridine derivatives 3 and 4 from 2-cyanoacetohydrazide 1 was described. The [1,2,4]triazolo[1,5-a]pyridine derivatives 10, 11 and 13-15 were obtained by reaction of 3 with ethyl chloroformate/DMF reagent mixture, acetic anhydride, triethyl orthoformate, -orthoacetate or aromatic aldehydes. Deamination of 3 to the aminopyridine derivatives 17 was carried out. The triazolopyridine derivatives 11 were obtained also in one step synthesis from 2 and N′-acetyl-2-cyanoacetohydrazide 19. Condensation of the thiohydantion 20 with 2 gave pyrano[2,3-d]imidazoles 24.