作者:Chamakura V. N. S. Varaprasad、Kanda S. Ramasamy、Zhi Hong
DOI:10.1002/jhet.5570430212
日期:2006.3
1,2,3,5-Tetra-O-acetyl-4-deoxy-4-(acetamido)-β-D-ribofuranose 5 was prepared from L-lyxose, which on condensation with silylated nucleoside bases gave the corresponding protected 4′-azanucleosides. The protecting groups were removed using methanolic ammonia to afford the N-acetyl-4′-azanucleosides, wherein the sugar ring oxygen is replaced with a substituted nitrogen atom, in good yields. Further,
由L-糖制备1,2,3,5-四-O-乙酰基-4-脱氧-4-(乙酰氨基)-β-D-呋喃核糖5,其在与甲硅烷基化的核苷碱基缩合后得到相应的被保护的4' -氮杂核苷。用甲醇氨除去保护基,得到N-乙酰基-4'-氮杂核苷,其中糖环氧被取代的氮原子取代,收率很高。此外,将1-(4-脱氧-4-乙酰胺基-β-D-呋喃呋喃糖基)胸腺嘧啶16转化为相应的2'-脱氧,2',3'-二脱氧衍生物。合成核苷的立体化学分配是基于NMR和X射线研究建立的。