The absolute configuration of (+)-α-methylserine ((+)-IX) obtained from natural source, has been elucidated to be S-configuration by the chemical correlation with (+)-isovaline ((+)-VII), at the same time the absolute configuration of (+)-2-amino-2-methyl-3-butenoic acid ((+)-XI) has also been proved to be S-series. Chemical schemes employed were shown in Charts 1 and 2. Optically active hydantoins (V and VIII) used in the correlation were prepared by the direct resolution of racemic hydantoins with brucine. Preliminary examinations using racemic compounds were also reported.
通过与(+)-异戊
氨酸((+)-VII)的
化学关联,从天然来源获得的(+)-α-甲基
丝氨酸((+)-IX)的绝对构型被阐明为 S 构型,同时(+)-
2-氨基-2-甲基-3-丁烯酸((+)-XI)的绝对构型也被证明为 S 系列。采用的
化学方案如图 1 和图 2 所示。相关研究中使用的光学活性海因(V 和 VIII)是通过外消旋海因与
丁二酸的直接分解制备的。还报告了使用外消旋化合物进行的初步研究。