a number of 3-amino-1, 2, 4-triazin-5 (2h)- ones(1) were synthesized and condensed with a-haloketones to give 2,6-disubstituted imidazo [1, 2-b] [1, 2, 4]-triazin-3 (4h)-ones (2). these compounds were reacted further with a - haloketones to yield n-alkylated products (3).

interpret the detailed mechanisms of reactions of tautomeric heterocycles properly. The correct dominant tautomeric structure also makes it possible to interpret the biological activity and functions of potential tautomeric heterocycles.1 Many of these aza/deaza analogues of purine and their nuclosides have drawn considerable interest in biological activity. Compound 6-amino-1,2,4-triazolo[3,4-...

1-Allyl- (2) and 7-allyl-6-amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H)-one (3) were obtained via the 18-crown-6-ether catalyzed room temperature reaction of 6-amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H)-one (1) with potassium carbonate and allyl bromide in dry acetone. The structures of these two derivatives were verified by 2D-NMR measurements, including gHSQC and gHM...

Reductive ring contraction of 1,3-diphenyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yls (Blatter's radicals) using zinc powder (2 equiv.) in acetic acid heated to ca. 118 °C gives 1,2-diphenylbenzimidazoles in high yield. 1,3-Diphenylbenzo[e][1,2,4]triazin-7(1H)-one and the zwitterionic tetraphenylhexaazaanthracene (TPHA) also undergo reductive ring contractions to give 1,2-diphenylbenzimidaz-6-ol a...