2‘-<i>C</i>-Branched Ribonucleosides. 2. Synthesis of 2‘-<i>C</i>-<i>β</i>-Trifluoromethyl Pyrimidine Ribonucleosides<sup>1</sup>
作者:Nan-Sheng Li、Xiao-Qing Tang、Joseph A. Piccirilli
DOI:10.1021/ol0155687
日期:2001.4.1
[structure: see text]. The first synthesis of 2'-C-beta-trifluoromethyl pyrimidine ribonucleosides is described. 1,2,3,5-Tetra-O-benzoyl-2-C-beta-trifluoromethyl-alpha-D-ribofuranose (3) is prepared from 1,3,5-tri-O-benzoyl-alpha-D-ribofuranose (1) in three steps and converted to 3,5-di-O-benzoyl-2-C-beta-trifluoromethyl-alpha-D-1-ribofuranosyl bromide (5). The 1-bromo derivative (5) is found to be
[结构:见文字]。描述了2'-C-β-三氟甲基嘧啶核糖核苷的首次合成。1,2,3,5-四-O-苯甲酰基-2-C-β-三氟甲基-α-D-呋喃核糖(3)由1,3,5-三-O-苯甲酰基-α-D-核呋喃糖制备(1)分三步,转化为3,5-二-O-苯甲酰基-2-C-β-三氟甲基-α-D-1-呋喃呋喃糖基溴化物(5)。发现1-溴衍生物(5)是用于合成核糖核苷的有力的反应中间体。在HgO / HgBr2存在下,甲硅烷基化的嘧啶与(5)的反应仅产生β-端基异构体(6-8)。用甲醇中的氨将(6-8)脱保护,得到2'-C-β-三氟甲基核苷(9-11)。