[摘要]：The stereoselective redn. of hexopyranos-5'-yl radicals in a-D-Hexp-(1?)-D-Hexp disaccharide models is described. These radicals are generated from a 6-O-yl radical located in the other monosaccharic unit through a 1,8-hydrogen atom transfer. The reaction, which is strongly influenced by steric and stereoelectronic effects, permits in some cases the transformation of a-D-Hexp-(1?)-D-Hexp into b-L-Hexp-(1?)-D-Hexp disaccharides in a single step with high diastereoselectivity.
