0-Glycosyl imidates synthesis

Mahlin, J.A., Jung, K.H., and Schmidt, R.R., Glycosyl imidates, synthesis of flavone C-glycosides vitexin, isovitexin and isoembigenin, Liebigs Ann. Chem., 3, 461, 1995. 

Glycoside Synthesis from 1-Oxygen-Substituted Glycosyl Imidates 143... 

This review covers the recent advances in the use of O-glycosyl imidates in oligosaccharide and glycoconjugate synthesis, with emphasis on literature published between 1999 and 2006. However, because of the large volume of work in this area, only the most representative applications will be presented. One can refer to the similar preceding review [381] published in 2000 and another quite comprehensive review [375] on trichloroacetimidate method published in 1994 for earlier application of glycosyl trichloroacetimidates. Trifluoroacetimidate method will be discussed separately in this review in the light of its less popularity in carbohydrate chemistry. 

Glycoside Synthesis from 7-Oxygen-Substituted Glycosyl Imidates 145... 

Glycoside Synthesis from i-Oxygen-Substituted Glycosyl Imidates 175... 

Scheme 18 Synthesis of the Core 1 (T-Antigen) Structure Using the Glycosyl Imidate[2781...

R. R. Schmidt and J. Michel, Facile synthesis of a- and [3-f7-glycosyl imidates preparation of glycosides and disaccharides, Angew. Chem. Int. Ed. Engl. 79 731 (1980). 

The coupling protocols described in the two previous examples can be combined to allow for the synthesis of branched carbohydrates.19 The automated solid-phase synthesis of a tetrasaccharide is illustrated in Scheme 4. Both glycosyl phosphate and glycosyl imidate building blocks were used along with acetate and levulinate esters as temporary protecting groups. 

SCHEME 6.28 Mong s stereoselective one-pot synthesis using DMF as the novel additive to facilitate the 1,2-as-glycoside formation, (a) The glycosyl imidates formed with DMF. (b) The one-pot synthesis of trisaccharide 142. 

Schmidt, R R, Michel, J, Roos, M, Glycosyl imidates. 12. Direct synthesis of O-a- and 0- 3-glycosyl imidates, Liebigs Ann. Chem., 12, 1343-1357, 1984. 

Bommer, R, Kinzy, W, Schmidt, R R, Glycosyl imidates. 49. Synthesis of the octasaccharide moiety of the dimeric Le antigen, Liebigs Ann. Chem., 425-433, 1991. 

Schmidt, R R, Effenberger, G, O-Glycosyl imidates. 29. Reaction of O-(glucopyranosyl) imidates with electron-rich heterocycles. Synthesis of C-glucosides, Liebigs Ann. Chem., 29, 825-831, 1987. 

J. Lassaletta and R. R. Schmidt, Glycosyl imidates. Part 75. Synthesis of the hexasaccharide moiety of globo H (human breast cancer) antigen, Liebigs Ann., (1996) 1417-1423. 

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