-tolylsulfonyl-2-enopyranoside ( 6 ) with nucleophiles (methoxide, nitromethane, 2,4-pentanedione, and ammonia) afforded the β- d - gluco adducts with high stereoselectivity. However, similar treatment of the phenyl analog 11 with sodium borodeuteride, nitromethane, methoxide, and lithium hydroxide led mainly to an S n 2′ process to give 1-enitol derivatives having the arabino configuration. Conversely, treatment of
摘要2-(甲基)2-C-对
甲苯磺酰基-2-烯
吡喃糖苷(6)与亲核试剂(
甲醇,
硝基甲烷,
2,4-戊二酮和
氨)反应,可得到立体选择性高的β-d-
葡萄糖加合物。然而,用
硼氢化氘化
钠,
硝基甲烷,
甲醇盐和
氢氧化锂对苯基类似物11进行类似处理,主要导致了S n 2'过程,从而得到具有
阿拉伯糖构型的1-烯醇衍
生物。相反,在
吡啶中用
羧酸处理11得到具有
核糖构型的1-烯醇衍
生物作为主要产物。