[C:1]([O:4][C@H:5]1[C@@H:11]([O:12][C:13](=[O:15])[CH3:14])[C@H:10]([O:16][C:17](=[O:19])[CH3:18])[C@@H:9]([CH2:20][O:21][C:22](=[O:24])[CH3:23])[O:8][CH:6]1[OH:7])(=[O:3])[CH3:2].[OH-].[K+].[CH2:27]([O:34]CCBr)[C:28]1C=CC=CC=1.C1C=CC=CC=1>S([O-])(O)(=O)=O.C([N+](CCCC)(CCCC)CCCC)CCC.C(OCOCC)C>[C:1]([O:4][C@H:5]1[C@@H:11]([O:12][C:13](=[O:15])[CH3:14])[C@H:10]([O:16][C:17](=[O:19])[CH3:18])[C@@H:9]([CH2:20][O:21][C:22](=[O:24])[CH3:23])[O:8][CH:6]1[O:7][CH2:28][CH2:27][OH:34])(=[O:3])[CH3:2]A mixture that consists of 34.83 g (100 mmol) of 2,3,4,6-tetra-O-acetyl-mannopyranose, 1.7 g (5 mmol) of tetrabutylammonium hydrogen sulfate and 82.93 g (600 mmol) of fine-powder potassium hydroxide in 350 ml of diethoxymethane is cooled to 0° C. At 0° C., 32.26 g (150 mmol) of 2-benzyloxy-ethylbromide is added in drops over 30 minutes while being stirred vigorously. It is stirred for two hours at 0° C. 300 ml of benzene is added, solid is filtered out, and the filtrate is evaporated to the dry state in a vacuum. The residue is taken up in 500 ml of ethanol. 5 g of palladium (10%) on activated carbon is added thereto and hydrogenated until hydrogen absorption is completed. Then, catalyst is suctioned out, it is rewashed with a little ethanol and evaporated to the dry state in a vacuum. The residue is chromatographed on silica gel (mobile solvent: dichloromethane/nhexane/ethanol=20:8:2). The product-containing fractions are concentrated by evaporation.
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