129.17, 129.14, 128.94 (each Ar-CH), 128.89, 128.64 (each Ar-C), 91.97 (C-1), 72.25 (C-5),
71.90 (C-3), 69.55 (C-4), 62.67 (C-6), 52.75 (C-2); HRMS (ESI): [M+H]
+ calcd. for
C34H30ClNO9, 596.1914; found 596.1909. Anal. Calcd for C34H30ClNO9: C, 64.61; H, 4.78; N,
2.22. Found: C, 64.84; H, 4.87; N, 2.33.
2-Acetylamino-1,3,4,6-tetra-O-benzoyl-2-deoxy-β-D-glucopyranose (5). Triethylamine
(3.15 mL, 22.6 mmol) was added at 0 °C to a solution of 4 (6.13 g, 9.7 mmol) in CH2Cl2 (80
mL) and the mixture was stirred until a clear solution was obtained. Acetyl chloride (0.80 mL,
11.2 mmol) was added with cooling (tap water), the mixture was allowed to warm to room
temperature and stirred for 16 h. The mixture was washed with water and brine, concentrated,
and chromatography (6:4 petroleum ether–EtOAc,) gave a colorless foam (4.9 g, 80%); [α]D =
-25.6 (c 2, CHCl3), (lit
8
[α]D
24 -19.3 (c 2, CHCl3);
1 H-NMR (500 MHz, CDCl3): δ 8.10 (m, J
= 7.7, 2H, Ar-H), 8.03 (m, J = 7.7, 2H, Ar-H), 7.96 (m, J = 7.7, 2H, Ar-H), 7.88 (m, J = 7.7,
2H, Ar-H), 7.58 (m, J = 7.5, 1H, Ar-H), 7.56 – 7.49 (m, 2H, Ar-H), 7.49 – 7.44 (m, 2H, Ar-H),
7.45 – 7.35 (m, 5H, Ar-H), 7.35 – 7.30 (m, 2H, Ar-H), 6.09 (d, J = 8.7, 1H, H-1), 5.84 (d, J =
9.6, 1H, NH), 5.80 (t, J = 9.7, 1H, H-4), 5.66 (dd, J = 10.8, 9.4, 1H, H-3), 4.80 (ddd, J = 10.8,
9.4, 8.7, 1H, H-2), 4.63 (dd, J = 12.4, 2.8, 1H, H-6a), 4.48 (dd, J = 12.4, 4.6, 1H, H-6b), 4.29
(ddd, J = 9.8, 4.6, 2.9, 1H, H-5), 1.80 (s, 3H,NHAc);
13 C NMR (126 MHz, CDCl3): δ 170.14,
167.02, 166.11, 165.15, 164.97 (each C=O), 133.84, 133.71, 133.49, 133.09, 130.30, 129.95,
129.82, 129.73 ( each Ar-CH), 129.49, 128.68 (each Ar-C), 128.59, 128.57, 128.53 (each ArCH), 128.45 (Ar-C), 128.42, 128.33 (each Ar-CH), 93.59 (C-1), 73.16 (C-2), 73.10 (C-3),
68.71 (C-4), 62.65 (C-5), 53.29 (C-6), 23.19 (OAc); HRMS (ESI): [M+H]
+ calcd. for
C36H31NO10Na
+ 660.1840; found 660.1840; Anal. Calcd for C36H31NO10: C, 67.81; H, 4.90; N,
2.20. Found: C, 68.03; H, 5.07; N, 2.29.
71.90 (C-3), 69.55 (C-4), 62.67 (C-6), 52.75 (C-2); HRMS (ESI): [M+H]
+ calcd. for
C34H30ClNO9, 596.1914; found 596.1909. Anal. Calcd for C34H30ClNO9: C, 64.61; H, 4.78; N,
2.22. Found: C, 64.84; H, 4.87; N, 2.33.
2-Acetylamino-1,3,4,6-tetra-O-benzoyl-2-deoxy-β-D-glucopyranose (5). Triethylamine
(3.15 mL, 22.6 mmol) was added at 0 °C to a solution of 4 (6.13 g, 9.7 mmol) in CH2Cl2 (80
mL) and the mixture was stirred until a clear solution was obtained. Acetyl chloride (0.80 mL,
11.2 mmol) was added with cooling (tap water), the mixture was allowed to warm to room
temperature and stirred for 16 h. The mixture was washed with water and brine, concentrated,
and chromatography (6:4 petroleum ether–EtOAc,) gave a colorless foam (4.9 g, 80%); [α]D =
-25.6 (c 2, CHCl3), (lit
8
[α]D
24 -19.3 (c 2, CHCl3);
1 H-NMR (500 MHz, CDCl3): δ 8.10 (m, J
= 7.7, 2H, Ar-H), 8.03 (m, J = 7.7, 2H, Ar-H), 7.96 (m, J = 7.7, 2H, Ar-H), 7.88 (m, J = 7.7,
2H, Ar-H), 7.58 (m, J = 7.5, 1H, Ar-H), 7.56 – 7.49 (m, 2H, Ar-H), 7.49 – 7.44 (m, 2H, Ar-H),
7.45 – 7.35 (m, 5H, Ar-H), 7.35 – 7.30 (m, 2H, Ar-H), 6.09 (d, J = 8.7, 1H, H-1), 5.84 (d, J =
9.6, 1H, NH), 5.80 (t, J = 9.7, 1H, H-4), 5.66 (dd, J = 10.8, 9.4, 1H, H-3), 4.80 (ddd, J = 10.8,
9.4, 8.7, 1H, H-2), 4.63 (dd, J = 12.4, 2.8, 1H, H-6a), 4.48 (dd, J = 12.4, 4.6, 1H, H-6b), 4.29
(ddd, J = 9.8, 4.6, 2.9, 1H, H-5), 1.80 (s, 3H,NHAc);
13 C NMR (126 MHz, CDCl3): δ 170.14,
167.02, 166.11, 165.15, 164.97 (each C=O), 133.84, 133.71, 133.49, 133.09, 130.30, 129.95,
129.82, 129.73 ( each Ar-CH), 129.49, 128.68 (each Ar-C), 128.59, 128.57, 128.53 (each ArCH), 128.45 (Ar-C), 128.42, 128.33 (each Ar-CH), 93.59 (C-1), 73.16 (C-2), 73.10 (C-3),
68.71 (C-4), 62.65 (C-5), 53.29 (C-6), 23.19 (OAc); HRMS (ESI): [M+H]
+ calcd. for
C36H31NO10Na
+ 660.1840; found 660.1840; Anal. Calcd for C36H31NO10: C, 67.81; H, 4.90; N,
2.20. Found: C, 68.03; H, 5.07; N, 2.29.