Abstract
The reaction of glycosyl isothiocyanate (1a) with thiourea in the presence of Mel-NEt3 gave a di-SMe compound (2a) and a mono-SMe compound (3a). Glycosyl isothiocyanates (1a, b, and c) reacted with amidino compounds (HN=CRNH3 ; R=H, Me, OMe, SMe, NH2) to afforded the corresponding glycosyl isothiobiurets (3a, c, and 6a, b), N-glycosyl-N'-amidino thioureides (4a, b, and 5a, b) or N-glycosyl-N'-guanidyl thioureides (7a and b) in good yields. Treatment of 3a, 6b, or 7a, b with HC (OEt)3 gave the corresponding s-triazine glycosides (8a, 9a, b, and 10b) in fair yields. On the other hand, similar treatment of 4a, b or 5a, b with HC (OEt)3 did not give s-triazine glycosides, but the starting material was recovered. N-Bromosuccinimide oxidation of 4a, b, 5a, b, 3a, c or 7a, b gave the corresponding 5-substituted-1, 2, 4-triazole-3-thiones (11a, b, 12a, b, or 14a, b) in excellent yields.
