Dc. Wei et al., CONDENSED AS-TRIAZINES - SYNTHESIS OF IMIDAZO[4,5-E]-AS-TRIAZINE 1-OXIDES (6-AZAPURINE 6-OXIDES) AS GUANINE AND HYPOXANTHINE ANALOGS, Heterocycles, 38(9), 1994, pp. 2009-2015
Imidazo[4,5-e]-as-triazine 1-oxides (6-azapurine 6-oxides), structural
ly related to guanine and hypoxanthine, have been prepared. Reaction o
f 5,6-diamino-3-methylsulfonyl-as-triazine 1-oxide(1) with hydrazine a
fforded 5,6-diamino-3-hydrazino-as-triazine 1-oxide(2) which was then
oxidized with mercuric oxide to give 5,6-diamino-as-triazinel-oxide(3)
. The 3-methylsulfonyl group of 1 was also replaced with liquid ammoni
a and methanolic ammonia respectively to give 3-amino (5) and 3-methox
y (6) derivatives. as-Triazine N-oxides were then cyclized with trieth
yl orthoformate (TEOF) to afford the title compounds.