摘要
在甲醇钠碱性条件下,以芦竹碱和N-乙酰氨基丙二酸二乙酯为原料进行缩合反应,缩合产物在4%的氢氧化钠水溶液中选择性水解脱羧得到N-乙酰-DL-色氨酸,然后在10%氢氧化钠水溶液中水解得到DL-色氨酸。DL-色氨酸用D-酒石酸拆分,并在苯甲醛催化下实现不对称转化,得到D-色氨酸D-酒石酸盐,最后用三乙胺中和得到目标产物D-色氨酸。确定了缩合和拆分步骤的适宜工艺条件。缩合步骤:甲醇钠摩尔量为芦竹碱的20%,n(芦竹碱)∶(N-乙酰氨基丙二酸二乙酯)=1∶1.2;拆分步骤:乙酸为溶剂,70℃反应,苯甲醛摩尔量为DL-色氨酸的10%,n(DL-色氨酸)∶n(D-酒石酸)=1∶2。
Gramine reacted with diethyl acetamldomalonate in the presence of sodium methoxide, the intermediate was selectively hydrolyzed in 4% aqueous solution of sodium hydroxide to give N-acetyl-DL- tryptophane, then DL-tryptophane was obtained through hydrolyzation using 10% aqueous solution of sodium hydroxide. The resolution was carried out with D-tartaric acid to give D- tryptophane D- tartaric acid salt, and benzaldehyde was used as catalyst to make asymmetric transformation. At last the salt was neutralized with triethylamine to give D-tryptophane. The optimum reaction conditions for condensation and resolving reaction were studied. For condensation reaction the molar ratio of sodium methoxide and gramine was 20%, and gramine : diethyl acetamidomalonate= 1 : 1.2 (tool) ; For resolving reaction acetic acid was used as solvent, 70℃ ,the molar ratio of benzaldehyde and DL-tryptophan was 10%, and DL- tryptophane : D-tartaric acid= 1 : 2(mol).
出处
《化学世界》
CAS
CSCD
北大核心
2012年第6期368-371,共4页
Chemical World
关键词
芦竹碱
D-色氨酸
D-酒石酸
不对称转化
gramine
D- tryptophane
D- tartaric acid
asymmetric transformation