愈创木酚-β-D-葡萄糖苷的合成及加香应用研究

Synthesis of guaiacol-β-D-glucopyranoside and its flavoring application

摘要:

为了提高愈创木酚的稳定性，以乙酰溴-α-D-葡萄糖（Ⅱ）为糖基供体和愈创木酚（I）进行反应，分别尝试银盐法、相转移催化法和离子液体法制备愈创木酚-2, 3, 4, 6-四-O-乙酰基-β-D-葡萄糖苷（Ⅲ），糖苷（Ⅲ）脱乙酰基得到目标产物愈创木酚-β-D-葡萄糖苷（Ⅳ）。中间体及产物结构经1HNMR、13CNMR、IR和HRMS确证。考察了糖苷Ⅳ的热稳定性和加香效果。结果表明：三种方法均可得到糖苷（Ⅲ），离子液体法优于相转移催化法及银盐法。离子液体法的反应条件为：1-丁基-3-甲基咪唑四氟硼酸盐（[bmim]BF4）为催化剂，无水K2CO3为缚酸剂，二氯甲烷为溶剂，n（愈创木酚）: n（乙酰溴-α-D-葡萄糖）=1.0 : 1.0，室温反应 4 h，糖苷Ⅲ的收率为 52.6%。糖苷Ⅲ在甲醇钠/甲醇体系中脱去乙酰基，得到目标糖苷Ⅳ。热重-差示扫描量热（TG-DSC）研究表明糖苷Ⅳ在228℃以下具有较好的热稳定性。将糖苷Ⅳ添加于卷烟中能够改善香气品质。

Abstract:

In order to improve the stability of guaiacol, a glycosylation reaction between 2, 3, 4, 6-tetra-O-acetyl-α-D-glucopyranosyl bromide (Ⅱ) and guaiacol(Ⅰ) led to guaiacol-2,3,4,6-tetra-O-acetyl-β-D-glucoside (Ⅲ) by silver salt method, phase transfer catalysis and ionic liquid method, respectively. Finally, guaiacol-β-D-glucoside (Ⅳ) was obtained by deacetylation of glucoside III. The structures of the intermediates and products were confirmed by 1HNMR, 13CNMR, IR and HRMS. The thermal stability of the target product (Ⅳ) was studied by thermogravimetric analysis and differential scanning calorimetry (TG-DSC). The flavoring effect of glycoside IV was investigated by sensory evaluation. The results show that glucoside Ⅲ synthesized by three above-mentioned methods was target product, ionic liquid method is better than phase transfer catalysis and silver salt method. The reaction conditions of ionic liquid method were as follows: 1-butyl-3-methylimidazole tetrafluoroborate ([bmim] BF4) as catalyst, anhydrous potassium carbonate as acid binding agent, dichloromethane as solvent, n (guaiacol) : n (bromotetraacetylglucose) = 1.0 :1.0, reaction at room temperature for 4 hours, and the yield of compound III was 52.6%. Compound III was deacetylated in sodium methoxide/methanol system to obtain the target product glycoside (Ⅳ). TG-DSC study showed that guaiacol- β- D-glucoside has good thermal stability below 228 ℃. Adding glycoside Ⅳ to cigarettes can improve the aroma quality.