Regio- and Stereoselective Glycosylation: Synthesis of 5-Haloimidazole α-Ribonucleosides
作者:Tilak Chandra、Xiang Zou、Edward J. Valente、Kenneth L. Brown
DOI:10.1021/jo060087s
日期:2006.6.1
We describe the synthesis of novel 5-haloimidazole ribonucleosides as precursors of modified cobalamins. A regio- and stereoselectiveglycosylation of protected ribose with silylated 4(5)-haloimidazoles produces 5-haloimidazole ribonucleosides predominantly in the α-configuration (60−75%) without any 4-substituted imidazole ribonucleoside. The structure of the 5-fluoroimidazole ribonucleoside was confirmed