稀有糖L-半乳糖及其衍生物的合成研究

Study on the Synthesis of Uncommon Sugar of L-galactose and Its Derivatives

摘要: 目的制备L-半乳糖及其中间体D-半乳糖醛酸、L-半乳糖酸-1，4-内酯，并优化工艺。方法采用酶法水解果胶，制备D-半乳糖醛酸，并用正交试验设计法确立最佳酶水解工艺；D-半乳糖醛酸经还原、脱水转化为L-半乳糖酸-1，4-内酯，进一步还原合成L-半乳糖。结果酶水解最佳条件为50℃反应2 h，酶-果胶比为1.5：10。合成产物结构经¹H-NMR、¹³C-NMR表征。合成产率为31.4%。结论方法操作简便，步骤短，反应收率高，具有工业化生产前景。

Abstract: OBJECTIVE L-galactose and its intermediate D-galacturonic acid and L-galactonic acid-1,4-lactones were prepared and optimized. METHODS D-galacturonic acid was prepared by enzymatic hydrolysis of pectin, and the best enzymatic hydrolysis technology was established by orthogonal experimental design. L-galactonic acid-1,4-lactones was synthesized from D-galacturonic acid via reduction and dehydration, L-galactose was synthesized from L-galactonic acid-1,4-lactones via reduction. RESULTS The optimum conditions for enzymatic hydrolysis were as follow:hydrolysis temperature was 50℃, The reaction time was 2 h, the enzyme-pectin ratio was 1.5:10. The structure of products were characterized by ¹H-NMR and ¹³C-NMR. The yield was 31.4%. CONCLUSION The method is simple and convenient, with short steps and high yield. It can be applied to industrial production.