Preparation of Optically Active Succinic Acid Derivatives. I. Optical Resolution of 2-Benzyl-3-(cis-hexahydroisoindolin-2-ylcarbonyl)propionic Acid.
作者:Toshiaki YAMAGUCHI、Takashi YANAGI、Hiroshi HOKARI、Yuko MUKAIYAMA、Tetsuhide KAMIJO、Iwao YAMAMOTO
DOI:10.1248/cpb.45.1518
日期:——
(+)-Monocalcium bis[(2S)-2-benzyl-3-(cis-hexahydroisoindolin-2-ylcarbonyl)propionate] dihydrate (KAD-1229, 1) is an optically active succinic acid calcium salt derivative with potent hypoglycemic effect. We investigated two optical resolution methods. 2-Benzyl-3-(cis-hexahydroisoindolin-2-ylcarbonyl)propionic acid 6 was esterified with (S)-N-benzyl mandelamide and the resulting diastereomeric esters were separated by column chromatography on silica gel to give 7 and 8 in 39.1% and 45.3% yields, respectively. The diastereomer 7 was hydrolyzed to give the optically active acid (-)-6. The absolute configuration of (-)-6 was established as S by comparison with an authentic sample. The alternative method was resolution using an optically active amine. Treatment of a solution of the racemic acid 6 with 0.65 eq of (R)-1-(1-naphthyl)ethylamine in ethanol gave the salt in 23.2% yield with an optical purity of 96.8% ee.
(+)-双[(2S)-2-苄基-3-(顺式六氢异吲哚啉-2-基羰基)丙酸]单钙盐二水合物(KAD-1229,1)是一种光学活性琥珀酸钙盐衍生物,具有强效降血糖作用。我们研究了两种光学解析方法。2-Benzyl-3-(cis-hexahydroisoindolin-2-ylcarbonyl)propionic acid 6 与 (S)-N-benzyl mandelamide 发生酯化反应,得到的非对映异构酯经硅胶柱层析分离,得到 7 和 8,产率分别为 39.1%和 45.3%。非对映异构体 7 经水解后得到光学活性酸 (-)-6。通过与真实样品对比,确定 (-)-6 的绝对构型为 S。另一种方法是使用光学活性胺进行解析。用 0.65 eq (R)-1-(1-萘基)乙胺在乙醇中处理外消旋酸 6 的溶液,得到的盐的产率为 23.2%,光学纯度为 96.8%ee。