Reaction Steps
1,2,3,4,6-Pentakis(3,4,5-tris(benzyloxy)benzoyl)-β-D-glucopyranoside (7.0 g, 3.1 mmol) was dissolved in a mixture of 200 mL of dry THF and 100 mL of dry MeOH and cooled to 0° C. Ammonia gas was bubbled through the solution for 10 min. The reaction was stirred at 0° C. for 30 min and then allowed to warm to rt and stirred for a further period of 2.5 h. Removal of the solvents followed by flash column chromatography eluting with 10%, 25% and then 50%, EtOAc in hexanes furnished 4.16 g (73%) of 2,3,4,6-tetrakis(3,4,5-tris(benzyloxy)benzoyl)-D-glucopyranose as a white solid froth (mixture of α,β anomers). A portion of this product (30 mg) was further purified by preparative TLC using 10% EtOAc in benzene. IR (CH2Cl2) 3483, 1725 cm−1; 1H NMR (CDCl3, 300 MHz) δ 7.42-6.64 (m, 68H), 6.23, (t, J=9.9 Hz, 1H), 5.79 (d, J=3.7 Hz, 1H), 5.70 (t, J=9.9 Hz, 1H), 5.75-4.65 (m, 27H), 4.29 (dd, J=4.3 Hz, 12.1 Hz, 1H), 3.40 (bs, 1H); 13C NMR (CDCl3, 90 MHz) δ 166.7, 165.7, 165.4, 165.1, 152.54, 152.50, 152.4, 143.1, 142.9, 142.8, 142.7, 142.6, 137.4, 137.35, 137.3, 136.6, 136.45, 136.4, 136.33, 136.3, 128.5, 128.4, 128.33, 128.2, 128.1, 128.07, 128.05, 128.0, 127.94, 127.9, 127.86, 127.8, 127.78, 127.56, 127.51, 127.4, 127.3, 124.6, 124.1, 123.9, 109.4, 109.3, 109.1, 90.4, 75.1, 75.0, 72.8, 71.2, 71.1, 70.9, 70.0, 67.6, 63.1; MS (+FAB) 1869 (MH+, 0.5). Anal. Calcd for C118H100O22 C, 75.80; H, 5.35; Found: C, 76.13: H, 5.45.
