The reaction of sugar 1 with silylated 5-alkoxymethyluracils 2a-c afforded
3a-c. Compounds 5a-c, 6a,b, 7a-c and 8c were prepared. Treatment of 4a,b wi
th tris (1H-1,2,4-triazole-1-yl) phosphine oxide ana subsequent reaction wi
th ammonia in dioxane, then with sodium methoxide yielded 9a,b.