C([O:4][C@H:5]1[C@H:18]([O:19]C(=O)C)[C@@H:17]([CH2:23][O:24]C(=O)C)[O:16][C@@H:7]([O:8][CH2:9][C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[C@@H:6]1[N:28]1[C:32](=[O:33])[C:31]2=[CH:34][CH:35]=[CH:36][CH:37]=[C:30]2[C:29]1=[O:38])(=O)C.C(OCC)(=O)C.C(O)C.CCCCCC>CO.C[O-].[Na+]>[C:29]1(=[O:38])[N:28]([C@@H:6]2[C@@H:5]([OH:4])[C@H:18]([OH:19])[C@@H:17]([CH2:23][OH:24])[O:16][C@@H:7]2[O:8][CH2:9][C:10]2[CH:11]=[CH:12][CH:13]=[CH:14][CH:15]=2)[C:32](=[O:33])[C:31]2=[CH:34][CH:35]=[CH:36][CH:37]=[C:30]12Benzyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranoside (3) (40.6 g, 84 mM) in 750 ml of dry methanol and 30 ml of 0.5M sodium methoxide was added to a 2 liter round bottomed flask equipped with magnetic stirring bar, saprum inlet and bent tube adapter and the contents stirred at room temperature for 18 hours. TLC indicated completion of the reaction. (The TLC solvent was 10:2:10 ethyl acetate: ethyl alcohol:hexane). To the mixture was added 15 g of Bio-Rad (Bio-Rad Laboratories, P.O. Box 708, 220Maple Ave., Rockville Center, N.Y. 11571) ion exchange resin AG-50W-X-8 (prewashed with H2O, methanol, and dried) and stirred for 5 minutes (pH should be ≤7.0). The mixture, after filtration followed by the removal of solvent, furnished benzyl 2-deoxy-2-phthalimido-α-D-glucopyranoside (1), 30 g (89.4% yield).
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