Syntheses of sulfur-containing nucleoside analogs

Reaction of glycosyl isothiocyanates (1a,b,c) with diazo compounds or chloroethylamine gave glycosylamino-1,2,3-thiadiazoles and glycosylimidazolidine-2-thiones. Similar reaction of 1a,b with ethanolamine afforded N-glycosyl-N'-hydroxyethylthioureides, followed by treatment of thionyl chloride to give glycosyliminothiazolidines. N-Glycosyl-N'-amidionthiocarboxamides were treated with thionyl chloride to give glycosyl s-triazin S-oxides. N-Glycosyl-N'-(6-amino-1,3-dimethyl-2,4-dioxopyrimidin-5-yl)thioureides were oxidized with NBS into pyrimidotriazine glycosides.