Application of intramolecular glycosidation to the stereocontrolled synthesis of disaccharides containing α-gluco and α-galacto linkages
作者:Mikael Bols
DOI:10.1039/c39930000791
日期:——
Disaccharides containing α-glucose and α-galactose linkages are stereospecifically synthesized from primary and secondary sugar hydroxy groups and a 2-hydroxythioglycoside via intramolecular glycosidation of a dimethylsilyl tethered intermediate.
Efficient stereocontrolled glycosidation of secondary sugar hydroxyls by silicon tethered intramolecular glycosidation
作者:Mikael Bols
DOI:10.1016/s0040-4020(01)80200-3
日期:1993.1
Dissaccharides containing 1.2-cis glycoside linkages were synthesized by an efficient stereocontrolled two step process involving a silicon tethering step, to a dimethylsilyl acetal followed by intramolecular glycosidation with N-iodosuccinimide in nitromethane.
The preparation and study of some novel glycosides of D-galactose
作者:Prabhakar A. Risbood、Lawrence A. Reed、Leon Goodman
DOI:10.1016/s0008-6215(00)85538-x
日期:1981.2
Abstract The tert -butyl- and the 2,2,2-trichloroethyl α- and β- D -galactopyranosides were prepared and both α- D -glycosides were selectively benzoylated to give the 2,3,6-tri- O -benzoyl- D -galactopyranosides. Cleaving of the glycosidic groups is described. The glycosides are useful intermediates for oligosaccharide synthesis where generation of a reducing sugar terminus under mild conditions is
gave alpha-chloride 15 as a major product. The glycosidation of sugar derivative 4 with sarsasapogenin 23 gave beta-glycoside 24 (29.1%) and alpha-glycoside 25 (46.9%), and that of 12 with 23 gave beta-glycoside 26 (24.0%) and alpha-glycoside 27 (40.8%). The improvement of the yields of beta-glycosides 24 and 26 (66.9 and 62.1% for 24 and 26, respectively) in the glycosidations were accomplished by the