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自木糖经过五步反应合成了2,3-内醚-5-去羟-β-D-核糖甲基甙(Ⅵ)。这五步反应是:D-木糖(Ⅰ)→D-木糖甲基呋喃甙(Ⅱ,α-和β-端基差向异构体混合物)→2,3,5-三-O-对甲苯磺酰基-β-D-木糖甲基呋喃甙(Ⅲ)→2,3-二-O-对甲苯磺酰基-5-去羟-5-碘代-β-D-木糖甲基呋喃甙(Ⅳ)→2,3-二-O-对甲苯磺酰基-5-去羟-β-D-木糖甲基甙(Ⅴ)→2,3-内醚-5-去羟-β-D-核糖甲基甙(Ⅵ)。总产率是18%。将已知的结晶的2-O-对甲苯磺酰基-β-D-木糖甲基呋喃甙(Ⅶ)进行对甲苯磺酰化,得到与上述完全相同的Ⅲ,这样就证明了Ⅲ的端基的构型。同时,也从β-D-木糖甲基吡喃甙(Ⅷ)制备了2,3,4-三-O-对甲苯磺酰基-β-D-木糖甲基吡喃甙(Ⅸ)。根据现有的知识肯定了合成的内醚糖的结构。
2,3-Endo-5-nor-β-D-ribose methyl glycoside (Ⅵ) was synthesized from xylose through five steps. The five-step reaction is: D-xylose (I) → D-xylose furanoside (II, mixture of α- and β-terminal epimers) → 2,3,5-tri-O- P-Toluenesulfonyl-β-D-xylose furanoside (Ⅲ) → 2,3-di-O-p-toluenesulfonyl-5-nor-5-iodo-β-D-xylosemethyl Furanoside (IV) → 2,3-di-O-p-toluenesulfonyl-5-nor-β-D-xylosidoside (Ⅴ) → 2,3-endo-5- -D-ribose methyl glycoside (Ⅵ). The total yield is 18%. The known crystalline 2-O-tosyl-β-D-xylose furanoside (VII) is tosylated to give exactly the same III as above, thus demonstrating that the end of III Configuration of the base. Meanwhile, 2,3,4-tri-O-p-toluenesulfonyl-β-D-xylose methylpyranoside (IX) was also prepared from β-D-xylose methylpyranoside (VIII). Based on current knowledge, the structure of the synthesized lactol was confirmed.