Nucleosides. Part LXI. A Simple Procedure for the Monomethylation of Protected and Unprotected Ribonucleosides in the 2?-O- and 3?-O-Position Using Diazomethane and the Catalyst Stannous Chloride
作者:Hagen Cramer、Wolfgang Pfleiderer
DOI:10.1002/hlca.19960790808
日期:1996.12.11
Intensive studies on the diazomethane methylation of the common ribonucleosides uridine, cytidine, adenosine, and guanosine and its derivatives were performed to obtain preferentially the 2′-O-methyl isomers. Methylation of 5′-O-(monomethoxytrityl)-N2-(4-nitrophenyl)ethoxycarbonyl-O6-[2-(4-nitrophenyl)ethyl]-guanosine (1) with diazomethane resulted in an almost quantitative yield of the 2′- and 3′-O-methyl
对常见核糖核苷尿苷,胞苷,腺苷和鸟苷及其衍生物的重氮甲烷甲基化进行了深入研究,以优先获得2'- O-甲基异构体。5'- O-(单甲氧基三苯甲基)-N 2-(4-硝基苯基)乙氧基羰基-O 6- [2-(4-硝基苯基)乙基]-鸟苷(1)的甲基化与重氮甲烷反应,几乎可以定量地得到2可以通过简单的硅胶快速色谱法(方案1)分离的′-和3′- O-甲基异构体。用重氮甲烷甲基化腺苷,胞苷和尿苷,同时保护和不保护5'- O-通过单-或二甲氧基三苯甲基基团的位置-和腺苷和胞苷的苷元部分被2-(4-硝基苯基)乙氧羰基(npeoc)基团(方案2-4)。尝试尽可能多地增加2'- O-甲基异构体的形成是基于各种溶剂,温度,催化剂和甲基化反应过程中催化剂的浓度。