Triester of (2S,3R,4R,5S,6R)-6-(acetyloxymethyl)-3-(((E)-4-methoxybenzylidene)amino)tetrahydro-2H-pyran-2,4,5-triacetate (4.0 g, 8.6 mmol) was used as a raw material and dissolved in preheated acetone (36 mL). Subsequently, 5 M HCl (2 mL) was slowly added to the solution and precipitation was observed. After cooling the reaction mixture to room temperature, ether (36 mL) was added and stirred continuously for 2 hours. The precipitate was collected by filtration, washed with ether and dried under reduced pressure to afford 1,3,4,6-tetra-O-acetyl-2-amino-2-deoxy-D-glucopyranose hydrochloride (2.9 g, 79%) as a white solid. The melting point of the product is 205°C (literature value: 231-233°C, ignition [49], melting point 235°C); specific optical rotation [α] 20D +36.6 (c 1.0, MeOH), literature value [49] +32 (H2O); infrared (IR) spectra (νmax 2939 cm1 (broad peak, NH3Cl), 1751 cm1 (C=O); 1H-NMR (DMSO-d6, 300 MHz) δ 1.95 (6H, s, CH3CO), 2.00 (3H, s, CH3CO), 2.14 (3H, s, CH3CO), 3.52 (1H, t, J = 9.7 Hz, H-2), 3.98 (2H, m, H-6, H-5), 4.15 (1H, dd, J = 12.3, 4.1 Hz, H-6), 4.87 (1H, t, J = 9.8 Hz, H-4), 5.28 (1H, t, J = 9.8 Hz, H-3), 5.84 (1H, d, J = 8.8 Hz, H-1), 8.26 (3H, s, NH3Cl).
