A General and Efficient Synthesis of Pyridin-2-yl <i>C</i>-Ribonucleosides Bearing Diverse Alkyl, Aryl, Amino, and Carbamoyl Groups in Position 6
作者:Martin Štefko、Lenka Slavětínská、Blanka Klepetářová、Michal Hocek
DOI:10.1021/jo902313g
日期:2010.1.15
good overall yield of 63%. This intermediate was then subjected to a series of palladium catalyzed cross-coupling reactions, aminations and aminocarbonylations to give a series of protected 1β-(6-alkyl-, 6-aryl-, 6-amino-, and 6-carbamoylpyridin-2-yl)-C-ribonucleosides. Deprotection of silylated nucleosides by Et3N·3HF gave a series of title free C-ribonucleosides (12 examples).
开发了一种高效,实用的方法制备6-取代的吡啶-2-基C-核糖核苷。一锅两步地将2-lithio-6-溴吡啶添加到TBS保护的核糖内酯中,然后乙酰化,得到1β-(6-溴吡啶-2-基)-1 - O-乙酰基2,3,5-三- ö - (叔丁基二甲基) - d -ribofuranose以高收率。用Et 3 SiH和BF 3 ·Et 2 O还原得到所需的TBS保护的6-溴吡啶C-核糖核苷作为纯β-端基异构体,总产率高达63%。然后对该中间体进行一系列钯催化的交叉偶联反应,胺化和氨基羰基化反应,得到一系列受保护的1β-(6-烷基-,6-芳基-,6-氨基-和6-氨基甲酰基吡啶-2-式)的C 1-核糖核苷。Et 3 N·3HF对甲硅烷基化的核苷进行脱保护得到了一系列无标题的C-核糖核苷(12个实例)。