甲基环戊烯醇酮-β-D-吡喃葡糖苷的合成及其热裂解

Synthesis and Pyrolysis of Methylcyclopentenolone-β-D-glucopyranoside

以D-葡萄糖为原料,分别合成了2,3,4,6-四-O-乙酰基-α-D-溴代吡喃葡糖苷(2,溴代葡萄糖法)和2,3,4,6-四-O-乙酰基-α-D-葡萄糖基三氯乙酰亚胺酯(4,三氯乙腈法),2和4再分别与甲基环戊烯醇酮(MCP)进行偶联反应,然后脱乙酰基制备了结构不同的MCP-β-D-葡糖苷[3-甲基-1-氧代环戊-2-烯基-β-D-吡喃葡糖苷(1)和5-甲基-1-氧代环戊-2-烯基-β-D-吡喃葡糖苷(1′)];用1H NMR和HRMS技术对中间体和产物的结构进行了表征;并研究了糖苷1和1′的热裂解。结果表明:1两种合成方法所得到的产物都是目标产物,溴代葡萄糖法优于三氯乙腈法;2溴代葡萄糖法的最佳反应条件为甲基环戊烯醇酮与化合物2的摩尔比为1∶1.2,温度35℃,反应时间5 h,目标产物的产率82.0%,反应总产率59.6%;3卷烟燃吸过程中,糖苷1和1′热裂解为甲基环戊烯醇酮后,其在主流烟气中的转移率分别为16.13%和16.40%。

Taking D-glucose as material, 2,3,4,6-Tetra-O-acetyl-α-D-glucopyranosyl bromide （Compound 2） and 2,3,4,6-Tetra-O-acetyl-α-D-glucopyranosyI trichloroacetimidate （Compound 4＇） were synthesized by c^-D-acetobromoglucose method （Method A） and trichloroacetonitrile method （Method B）, respectively. Compounds 2 and 4＇ were coupled with methylcyclopentenolone （MCP）, then deacetylated to form MCP-/3-D-glucopyranosides [3-methyl-l-oxocyclopenta-2-en-2-yl-/3-D-glucopyranoside （Compound 1） and 5-methyl-l-oxocyclopenta-2-en-2-yl-/3-D-glucopyranoside （Compound 1＇ ）, respectively. The molecular structures of intermediates and final products were characterized by ~H NMR and HRMS. The thermal pyrolysis of glucosides 1 and 1＇ was also studied, and the results indicated that： 1） The compounds synthesized by the two methods were target products, Method A was better than Method B. 2） The optimal conditions of Method A were the molar ratio of MCP to compound 2 1：1.2 and reacting at 35 ℃ for 5 hours, the yield of target product reached 82.0% and the total yield of reaction was 59.6%. 3） Glucosides 1 and 1＇ were added into cigarettes separately, the glucosides pyrolyzed into MCP during smoking, and their transfer rates to mainstream cigarette smoke were 16.13% and 16.40%, respectively.