α-Chymotrypsin and<scp>l</scp>-acylase aided synthesis of 5-hydroxypipecolic acid via Jacobsen's hydrolytic kinetic resolution of epoxy amino acids
作者:Suvratha Krishnamurthy、Jalli Venkataprasad、Tarun Chand Vagvala、Tetsuji Moriguchi、Akihiko Tsuge
DOI:10.1039/c5ra09207h
日期:——
used to synthesize racemic 2-amino-5-hexenoic acid. These racemic 2-amino-5-hexenoic acid (homoallylyglycine) derivatives were efficiently resolved aided by α-chymotrypsin or L-acylase, giving rise to L- and D-enantiomers. These isolated enantiomerically pure amino acids with tert-butoxycarbonyl (Boc) protection were oxidised with 3-chloroperbenzoic acid. The oxidation gave rise to inseparable diastereomeric
丙二酸二乙酯衍生物用于合成外消旋的2-氨基-5-己酸。这些外消旋的2-氨基-5-己烯酸(homoallylyglycine)衍生物有效的解决由α胰凝乳蛋白酶或资助大号-acylase,产生大号-和d -对映体。将这些具有叔丁氧羰基(Boc)保护的对映体纯的氨基酸用3-氯过苯甲酸氧化。由于在C 5上新生成的手性中心,氧化产生了不可分割的非对映体环氧化物碳。通过将剩余的非对映异构体选择性转化为由Jacobsen水解动力学拆分(HKR)催化的二羟基化合物,可以分离出一种非对映异构体环氧化物。分离出的环氧化物被溴化锂区域选择性地攻击,得到邻卤代醇,而溴化物攻击末端的C 6碳。卤代醇的Boc脱保护通过游离胺攻击C 6碳而导致分子内环化,生成了5-羟基哌酸的单一异构体,在用Boc基团对胺进行重新保护后,毫不费力地回收了该异构体。同样,较早分离出的二羟基化合物在C 6处被碘转化为卤代醇。碳。通过用催化性Bu