An efficient asymmetric synthesis of D-α-amino acid derivatives (VI) has been achieved by alkylation of the Schiff base (III), prepared from glycine tert-butyl ester and (1S, 2S, 5S)-2-hydroxypinan-3-one (II), followed by hydrolytic cleavage of the alkylated Schiff base (V). The chiral source (II) was also recovered in good yield, allowing the proliferation of the asymmetry according to the cycle of the amino acid asymmetric synthesis shown in Chart 1.
已通过对由
甘氨酸叔丁酯和(1S, 2S, 5S)-2-羟基
匹那酮(II)制备的希夫碱(III)进行烷基化,随后对烷基化希夫碱(V)进行
水解断裂,实现了高效的不对称合成 D-
α-氨基酸衍
生物(VI)。手性来源(II)也以良好的产率回收,从而促进了根据图1所示的
氨基酸不对称合成循环实现不对称的扩展。