Enantio- and diastereoisomers of 2,4-dimethoxy-5-(2,3-dideoxy-5-O-tritylribofuranosyl)pyrimidine. 2',3'-Dideoxy pyrimidine C-nucleosides by palladium-mediated glycal-aglycon coupling
作者:Han Cheng Zhang、G. Doyle Daves
DOI:10.1021/jo00061a034
日期:1993.4
Newly available enantiomeric 2,3-dideoxy glycals, (5S)- and (5R)-4,5-dihydro-5-[(triphenylmethoxy)-methyl] furans and 2,4-dimethoxy-5-iodopyrimidine undergo palladium-mediated coupling by two different, complementary procedures to form enantiomeric pairs of (2',3'-dideoxy-2',3'-didehydrofuranosyl)- and (2',3'-dideoxy-3',4'-didehydrofuranosyl)pyrimidine C-nucleosides. Stereoselective reductions of the carbohydrate unsaturations produce all four enantio- and diastereoisomers of 2,4-dimethoxy-5-(2,3-dideoxy-5-O-tritylribofuranosyl)pyrimidine. The facile two-step syntheses of 2',3'-deoxy C-nucleosides which involves preparation of a D-series C-nucleoside from an L-series glycal (and vice versa) represents a new strategy for C-nucleoside synthesis.