The combined use of silanes (Et3SiH or PMHS) and I-2 as novel N-glycosidation reagents for the synthesis of bioactive oxathiolane nucleosides 3TC and FTC is reported. Both systems (working as anhydrous HI sources) were devised to act as substrate activators and N-glycosidation promoters. Excellent results in terms of chemical efficiency and stereoselectivity of the reactions were obtained; surprisingly, the nature of the protective group at the N4 position of (fluoro)cytosine additionally influenced the stereochemical reaction outcome.
Diastereoselective Synthesis of the Potent Antiviral Agent (-)-2'-Deoxy-3'-thiacytidine and Its Enantiomer
作者:Haolun Jin、M. Arshad Siddiqui、Colleen A. Evans、H. L. Allan Tse、Tarek S. Mansour、Michael D. Goodyear、Paul Ravenscroft、Christopher D. Beels