L-薄荷基-β-D-葡萄糖苷的合成

Synthesis of L-Menthyl β-D-Glucoside

为了提高L-薄荷醇的热稳定性,考察了合成L-薄荷基-β-D-葡萄糖苷的几种偶联方法及其相关保护与脱保护反应,探讨了D-葡萄糖五乙酸酯与L-薄荷醇的偶联反应条件,并对合成产物的熔点、比旋光度、NMR、MS和TG进行了分析。结果表明:①以葡萄糖和L-薄荷醇为原料,通过乙酰化、偶联、脱保护三步反应可合成L-薄荷基-β-D-葡萄糖苷;②合成产物为目标产物;③偶联反应的适宜条件:溶剂CH2C l2,n(D-葡萄糖五乙酸酯)∶n(L-薄荷醇)∶n(BF3.Et2O)=1∶3∶5,反应温度25℃,反应时间10 h,合成产率40%;④合成产物L-薄荷基-β-D-葡萄糖苷的热稳定性高。

In order to improve the thermal stability of L-menthol,several coupling methods and their related protection and deprotection reactions for L-menthyl β-Dglucoside synthesizing were investigated,the coupling reaction conditions of β-D-glucose pentaacetate with L-menthol were discussed,and the melting point,optical rotation,NMR,MS and TG of the synthesized product were analyzed.The results showed that： 1） it is feasible to synthesize L-menthyl β-D-glucoside from glucose and L-menthol through three-step reaction of acetylation,coupling, and deprotection;2） the synthesized product is the target product;3） the optimized condition of coupling reaction was solvent CH2Cl2,n（β-D-glucose pentaacetate）：n（L-menthol）：n（BF3·Et2O）=1∶3∶5,reaction temperature 25 ℃,and reaction time 10 hours,at which the yield reached 40%;4） the synthesized product,L-menthyl β-D-glucoside,featured high thermal stability.