(R)-四氢噻唑-2-硫酮-4-羧酸的合成及其晶体结构

Synthesis and Crystal Structure of (R)-Thiazolidine-2-thione-4-carb Acid

由L-半胱氨酸盐酸盐与二硫化碳在NaOH及CuSO4·H2O存在下反应得到（R）-四氢噻唑-2-疏酮-4－羧酸，[α]20D—87．5°，产率66％．用X射线衍射法测得其晶体结构，属正交晶系，Pz1z1z1空间群，晶体学参数：α＝0．5029（2）nm，b＝0．7749（5）nm，c＝1．6300（5）nm，V＝0．6350（5）nm3，Z＝4．用分子轨道（PM3）方法研究了该化合物的电子结构，得到其前线轨道性质．电荷和键序分布，并讨论了活性部位．

The title compound with [α]20D-87. 5°and yield 66% was prepared by the reaction of L-cysteine hydrochloride monohydrate and carbondisulfide in the presence of sodium hy-droxide and cupric sulfate hydrate. The crystal structure was determined by X-ray diffraction method. The crystal is orthorhombic system, space group Pz1z1z1, a=0.502 9(2) nm, b=0. 774 9(5) nm, c=1. 630 0(5) nm, V=0. 635 0(5) nm3, z=4. The electronic structure of the title compound was studied by molecular orbital PM3 method- The nature of the near frontier orbital and distribution of the calculated net charges and bond orders were obtained.The active site was described.