Aldonhydroximo-lactones. Preparation and Determination of Configuration
作者:Dieter Beer、Andrea Vasella
DOI:10.1002/hlca.19850680821
日期:1985.12.18
D-galactose, D-mannose, 2-acetamido-2-deoxy-D-glucose, D-ribose, and D-arabinose oxime with MnO2, Hg(OAc)2, or O2 in the presence of Cu2Cl2/pyridine are described. An (E/Z)-pair of protected hydroximo-lactones 14 and 15 was obtained by oxidation of the diisopropylidene-D-mannose oxime 13 with MnO2. In CH2Cl2 solution, the minor (E)-isomer 15 was slowly transformed into the major (Z)-isomer 14. The structure
通过D-葡萄糖,纤维二糖,D-半乳糖,D-甘露糖,2-乙酰氨基-2-脱氧-D-葡萄糖,D的氧化,合成未保护的,(Z)构型的(Z)构型的六氢和五氢己酮内酯2a - 12a。描述了在Cu 2 Cl 2 /吡啶存在下具有MnO 2,Hg(OAc)2或O 2的R-核糖和D-阿拉伯糖肟。通过用MnO 2氧化二异亚丙基-D-甘露糖肟13,得到(E / Z)对保护的羟基内酯14和15。在CH 2 Cl 2中在溶液中,次要(E)异构体15慢慢转变成主要(Z)异构体14。2a–12a的结构分配基于IR和NMR数据,1和14的贝克曼重排以及7a和47的X射线结构分析。从选择性脱保护的羟基内酯2c,8c和9c制备氨基甲酸酯2d,2f,8d和9d。(E / Z)-氨基磷酸酯的混合物27 / 28,29 / 30和31/32是从bromonitroso醚得到的16,19,和17和磷酸钠(OET)2。溴亚硝基醚18和