Asymmetric Synthesis of OrthogonallyProtected (2<i>S</i>,4<i>R</i>)-and (2<i>S</i>,4<i>S</i>)-4-Hydroxyornithine
作者:Jieping Zhu、Renaud Lépine、Anny-Claude Carbonnelle
DOI:10.1055/s-2003-40840
日期:——
Synthesis of orthogonally protected (2S, 4R)- and (2S, 4S)-4-hydroxyornithine was reported featuring an asymmetric alkylation of N-(diphenylmethylene)glycine tert-butyl ester (6) by (5S)-N-benzyloxycarbonyl-5-iodomethyl oxazolidine (7). Double stereoselection was examined using chiral ammonium salts as phase transfer catalysts and a substrate-directed chiral induction is documented.
(2S, 4R)- 和 (2S, 4S)-4-hydroxyornithine 的正交保护(2S, 4R)- 和 (2S, 4S)-4-hydroxyornithine 的合成方法是 (5S)-N-苄氧羰基-5-碘甲基噁唑烷 (7) 对 N-(二苯亚甲基)甘氨酸叔丁酯 (6) 进行不对称烷基化。使用手性铵盐作为相转移催化剂对双立体选择进行了研究,并记录了底物导向的手性诱导。