【摘要】 本文研究了1-(2,3,4-三-O-苯甲酰-β-D-吡喃木糖基)-偕氨基肟与酸酐及酰氯的缩合反应,探讨了不同缩合剂、不同取代基对环合反应的影响,与酸酐反应可以一步完成,且收率较好;与酰氯反应分两步进行,第一步酰化,第二步脱水环合,芳环上取代基的电性效应,决定环合反应的难易,并证明了该环系的碳苷对酸、碱、热具有化学稳定性,本文合成了12个氧杂二唑类木糖碳苷及2个木糖基化的开环产物,通过光谱及元素分析,确定了它们的结构。更多还原

【Abstract】 Fourteen new derivatives of 3-β-D-xylopyranosyl 1,2,4-oxadiazole were synthesized via condensating protected β-D-xylopyranosyl amidoxime with anhydrides or various substituted benzoyl chlorides in good yields. The 1,2,4-oxadiazole ring was formed directly by condensation of xylopyranosyl amidoxime and various anhydrides, but if the condensation occured by using substituted benzoyl chloride instead of anhydride, the cyclization was completed by two steps. The mechanism was discussed, 3-β-.D-xylopyranosyl-1,2,4-oxadiazole is stable under the condition of 1 mol/L HC1, 1 mol/L NaOH or at high temperature.更多还原