was higher and 21% could be isolated. Reaction of 3 with hot ethanolic hydrogen chloride afforded a good yield of ethyl 2-deoxy-2-[(2,2-diethoxycarbonylvinyl)amino]-α- d -glucopyranoside. On the other hand, attempted glycosidations of 2-deoxy-2-[(2,2-diacetylvinyl)amino]-α- d -glucopyranose under similar conditions were unsuccessful. The 2,2-diacylvinyl group could be removed selectively under non-acidic
摘要2-脱氧-2-[((2,2-二甲氧基羰基
乙烯基)
氨基]-(1)和2-脱氧-2-[(2,2-二乙氧基羰基
乙烯基)
氨基]-α-d-
吡喃
葡萄糖(3)的制备在通过Fischer方法制备糖苷时,将合适的3-烷氧基-2-烷氧基羰基
丙烯酸酯和2-
氨基-2-脱氧-d-
葡萄糖盐酸盐的几乎定量的收率用作N-保护的衍
生物。用沸腾的
氯化氢甲醇对1进行糖基化,得到甲基2-脱氧-2-[(2,2-二甲氧基羰基
乙烯基)
氨基]-α-(7α)和-β-d-
吡喃
葡萄糖苷(7β)的混合物,甲基2-脱氧-2-[((2,2-二甲氧基羰基
乙烯基)
氨基]-α-d-
葡糖呋喃糖苷(18);易于分离7α(55%的收率)。使用Amberlyst-15(H +)
树脂作为催化剂,
呋喃糖苷18的比例更高,可以分离出21%。3与热的
乙醇氯化氢反应,得到乙基2-脱氧-2-[(2,2-二乙氧基羰基
乙烯基)
氨基]-α-d-
吡喃
葡萄糖苷的良好产率。另一方面,