Bridged C-disaccharides

R. R, Schmidt and R. Preuss, Synthesis of carbon bridged C-disaccharides, Tetrahedron Lea. 30 3409 (1989) B. Giese, M. Hoch, C. Lamberth, and R. R. Schmidt, Synthesis of methylene bridged C-disaccharides, Tetrahedron Lett. 29 1375 (1988). 

Preuss, R, Schmidt, R R, Synthesis of methylene bridged C-disaccharides, J. Carbohydr. Chem., 10, 887-900, 1991. 

O-acetyl-D-glucopyranosyl bromide. Subsequent 1,4-addition of this radical species yielded the desired methylene-bridged C-disaccharide with good stereoselectivity and a 45% yield for the overall sequence. 

Beginning with the use of acetylene anions, Armstrong, eta/.,18 prepared linear acetylene-bridged C-disaccharides. An example of the synthetic... 

The 1,3-dipolar cycloaddition of exocyclic methylenes with nitrile oxides has already been addressed in section 2.13.10 This work, shown in Scheme 8.4.2, is notable in that high stereoselectivity in the resulting isoxazoline can be obtained. This is presumably the consequence of the bulk of the nitrile oxide directing approach to the a face of the sugar methylene. Through the use of these reactions, C-disaccharides, bridged by isoxazoline rings have been made accessible. 

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