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以新手性拆分试剂Ｒ（－）四氢噻唑－２－硫酮－４－羧酸［简称Ｒ（－）ＴＴＣＡ］对Ｄ，Ｌ－氨基酸酯进行手性拆分，分别得到（Ｒ）ＴＴＣＡ氨基酸酯盐１ａ＿１ｆ（［α］２０Ｄ＝－３０．４０°～－４２．７０°）及光学活性氨基酸酯２ａ＿２ｆ，其光学纯度为３５．４％～７５．８％．由１ａ＿１ｆ在碱存在下分解出２ａ＿２ｆ的对映体３ａ＿３ｆ，光学纯度为３９．５０％～６９．１０％．用半经验的量子化学ＰＭ３方法研究了氨基的碱性、中间产物铵盐生成热和稳定性．
Chiral resolution of the D, L-amino acid esters with the new chiral resolving reagent R (-) tetrahydrothiazole-2-thione-4-carboxylic acid [abbreviated as R (-) TTCA] gave (R) TTCA The amino acid ester salt 1a_1f ([α] 20D = -30.40 ° -42.70 °) and the optically active amino acid ester 2a_2f have an optical purity of 35.4% -75.8%. The enantiomer 3a_3f of 2a_2f was decomposed from 1a_1f in the presence of base, and the optical purity was 39.50% ~ 69.10%. A semi-empirical quantum chemical method PM3 was used to study the heat and stability of the basic and intermediate ammonium salts of amino groups.