Glycoconjugates preparation

Carboxymethyl glycoside lactones are easily prepared by diverse routes and react readily with nucleophilic species. Their reaction with amines, a simple addition which does not require any intermediate activation, is very general, and many examples of new pseudo-glycoconjugates prepared by this method are described. Moreover, 1,2-bisfunctionalized carbohydrate systems are efficiently constructed by reaction of the free OH on position 2 obtained after the opening of the lactone ring. Applications at the frontier of materials and biology have been envisaged and further studies in these fields will be reported in the near future. 

Oliver, C.M., Melton, L.D., and Stanley, R.A. (2006b). Functional properties of caseinate glycoconjugates prepared by controlled heating in the dry state. ]. Sci. Food Agric. 86, 732-740. 

Indeed, a variety of Lewis acids have been shown to effed glycosylation with hemiacetal donors. Ernst and coworkers have used 5mol% of [Rh(III)(MeCN)3 (triphos)] tris(triflate) with 4 A molecular sieves to prepare glycoconjugates 18 and 19 [26]. Mukaiyama s group has used trityl tetrakis(pentafluorophenyl)borate (3-5 mol%) with Drierite in the preparation of disaccharides 20 and 21 [27,28]. In the synthesis of 21, the a-seledivity was shown to arise from in situ anomerization of the (1-pyranoside over time. 

Dick Jr WE, Beurret M (1989) Glycoconjugates of bacterial carbohydrate antigens. In Cruse JM, Lewis Jr RE (eds) Contrib Microbiol Immunol. Karger, Basel, vol 10, p 48 Jennings HJ, Sood RK (1994) Synthetic giycoconjugates as human vaccines. In Lee YC, Lee RT (eds) Neoglycoconjugates preparation and applications. Academic Press, San Diego, p 325... 

Jennings HJ, Sood RK (1994) Synthetic glycoconjugates as human vaccines. In Lee YC, Lee RT (eds) Neoglycoconjugates preparation and applications. Academic Press, San Diego, p 325... 

J. E. Heidlas, K. W. Williams, and G. M. Whitesides, Nucleoside phosphate sugars Syntheses on practical scales for use as reagents in the enzymatic preparation of oligosaccharides and glycoconjugates, Acc. Chem. Res. 25 307 (1992). 

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