1,5-苯并硫氮杂-β-内酰胺衍生物的不对称合成及晶体结构

Asymmetric Synthesis and Crystal Structure of β-Lactam Derivatives of 1,5-Benzothiazepines

用 ( -) -4 R-苯基唑烷酮为手性诱导试剂 ,N-端保护的 N-乙酰氯与 1 ,5 -苯并硫氮杂反应合成了 5个具有光学活性的 1 ,5 -苯并硫氮杂 -β-内酰胺衍生物 ,并通过 1 H NMR,MS,IR,[α]2 0D 和元素分析对此类化合物进行了表征 ,用 X射线衍射法确定了产物 b的立体结构 .晶体 X射线衍射分析结果表明 ,化合物 b属单斜晶系 ,P2 1 2 1 2 1 空间群 ,晶胞参数 :Mr=5 5 3.0 5 ,a=1 .2 2 93( 2 ) nm,b=2 .6 0 2 6 ( 5 ) nm,c=1 .0 1 4 6 ( 2 ) nm,β=90°,V=3.2 4 6 1 nm3 ,Z=4 ,Dc=1 .31 2 g/ cm3 ,F ( 0 0 0 ) =1 34 4 ,R1 =0 .0 5 84 ,w R2 =0 .1 1 4 0 .该化合物分子中七元杂环为类椅式构象 。

Five optially active β lactam derivatives of 1,5 benzothiazepine have been synthesized by the reaction of 1,5 benzothiazepines with N protected glycine chloride using chiral oxazolidone as the chiral auxiliary and characterized by elementary analysis , IR, 1H NMR, MS and 20 D. The crystal structure of compound Ⅱb was determined by single crystal X ray diffraction. Crystal data: M r=5 53.05, monoclinic with P 2 12 12 1 space group, a = 1.229 3(2) nm, b = 2.602 6(5) nm, c = 1.014 6(2) nm, β =90°, V = 3.246 1(10) nm 3, F (000)= 1 344, Z =4, D c= 1.312 g/cm 3, R = 0.058 4, wR = 0.114 0. The structure analysis reveals that the conformation of sever membered ring is chair like, the substituents at C8 and C9 in β lactam ring are located on the same side.