论文部分内容阅读
自2,3-内醚-α-和β-D-来苏糖甲基呋喃甙(Ⅳ,α和β)合成了2,3-内醚5-去羟-α-和β-D-来苏糖甲基甙(Ⅶ,α和β).合成的步骤为:2,3-内醚-α-和β-D-来苏糖甲基呋喃甙(Ⅳ,α和β)→2,3-内醚-5-O-对甲苯矿酰基-α-和β-D-来苏糖甲基呋喃甙(V,α和β)→2,3-内醚-5-碘代-5-去羟-α-和β-D-来苏糖甲基甙(Ⅵ,α和β)→2,3-内醚-5-去羟-α-和β-D-来苏糖甲基甙(Ⅶ,α和β).除了最后一对外,其余的中间物都是结晶的. 本工作得到了结晶的2-O-对甲苯矿酰基-3,5-异丙亚基-α-和β-D-木糖甲基呋喃甙(Ⅱ,α和β).水解后,α-端基差向异构体生成美丽的2-O-对甲苯矿酰基-α-D-木糖甲基呋喃甙(Ⅲα,R=Ts)晶体,可是在同样的处理下,β-端基差向异构体却只是糖浆状产物(Ⅲβ,R=Ts).
2,3-Endo-ether 5-nor-α-and β-D- were synthesized from 2,3-endo-α- and β-D-lyxitofuranoside (Ⅳ, α and β) (Ⅶ, α and β). The synthetic steps are: 2,3-Indole-α- and β-D-lyxose methylfuranoside (Ⅳ, α and β) → 2,3 -endol-5-O-p -toluomiyl-a- and β-D-lyxosemethylfuranoside (V, α and β) → 2,3-endo-5- Hydroxy-α- and β-D-lyximethylglycoside (Ⅵ, α and β) → 2,3-endo-ether-5-noroxymethyl- and β-D- , α, and β). The rest of the intermediate was crystallized except for the last pair. This work has resulted in the crystallization of 2-O-p-toluene-toluene acyl-3,5-isopropylidene-α- and β-D - xylose furanoside (II, alpha and beta). After hydrolysis, the a-terminal epimer produces the beautiful 2-O-p -toluene acyl-alpha-D-xylose furanoside III ?, R = Ts) crystals, but the? -terminal epimers were only syrupy products (III?, R = Ts) under the same treatment.