Asymmetric synthesis of unusual amino acids: Synthesis of optically pure isomers of N-indole- (2-mesitylenesulfonyl)-β-methyltryptophan
作者:Lakmal W. Boteju、Kirsten Wegner、Xinhua Qian、Victor J. Hruby
DOI:10.1016/s0040-4020(01)86957-x
日期:1994.2
We have developed methods for the synthesis of the four optically pure isomers of β-methyltryptophan with the 2-mesitylenesulfonyl indole protecting group for peptide synthesis. Starting from 3-indoleacrylic acid, the β-methyl function was generated by a chiral auxiliary-directed asymmetric conjugate 1,4-addition. Asymmetric bromination was achieved via a tandem addition of N-bromosuccinimide to the
我们已经开发了用于合成具有β-甲基色氨酸的四个光学纯的异构体的方法,所述异构体具有用于肽合成的2-亚甲基亚磺酰基吲哚保护基。由3-吲哚丙烯酸开始,通过手性辅助定向的不对称共轭物1,4-加成反应生成β-甲基官能团。通过将N-溴代琥珀酰亚胺串联添加到通过共轭物添加形成的烯醇化物中,实现了不对称溴化。叠氮化物置换溴化物,手性助剂水解然后还原,产生了两种赤型异构体。共轭加合物的手性酰亚胺烯酸酯叠氮化,手性助剂的水解和还原产生了高光学纯度的两种苏式异构体。