Molecules 2009, 14
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8.09 (m, 4H, Ph);13C-NMR δ (ppm) (CDCl3): 20.5 (CH3CO), 20.7 (CH3CO), 20.8 (CH3CO), 20.9
(CH3CO), 51.9 (OCH3), 61.4 (C-sugar), 67.4 (C-sugar), 69.8 (C-sugar), 70.0 (C-sugar), 90.4(C-1),
124.6 (Ph), 128.7 (Ph), 130.8 (Ph), 132.0 (Ph), 134.0 (Ph), 145.9 (Ph), 166.5 (C=O), 168.7 (CH3CO),
169.9 (CH3CO), 170.7 (CH3CO), 172.4 (CH3CO); ESI-TOF-MS: [M+Na]+ m/z 519.1.
3.2.4. Synthesis and Spectral Data of 4a-c
The appropriate compound 3a-c (2.0 g, 7.4 mmol) was dissolved in THF (50 mL) and acetic acid
(5 mL). Under stirring, zinc power (1.3 g, 20 mmol) was added slowly. The mixture was then refluxed
for 2 h, cooled to room temperature, and filtered through a short column of silica gel. The eluent was
evaporated to dryness under vacuum. The residue was dissolved in ethyl acetate and washed
sequentially with saturated sodium hydrogen carbonate solution, saturated brine and water. The
organic layer was dried over anhydrous Na2SO4 and evaporated under reduced pressure to afford the
compounds 4a-c as yellow solids.
Methyl-6-(o-amino)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-glucopyranoside (4a). Yield: 88.0%;
mp: 108-110 ºC; []D +98o (c 1.01, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.01 (s, 3H, Ac), 2.07 (s, 3H,
Ac), 2.09 (s, 3H, Ac), 3.43 (s, 3H, OCH3), 3.61 (m, 1H, H-6), 3.79 (m, 1H, H-5), 4.04 (m, 1H, H-6),
4.83 (dd, 1H, J1,2 3.6 Hz, J2,3 9.6 Hz, H-2), 4.93 (m, 2H, H-1, 3), 5.50 (t, 1H, J 9.6 Hz, H-3), 5.48 (t,
13
1H, J 9.9 Hz, H-4), 6.45 (t, 1H, H-NH), 6.45-7.36 (m, 4H, Ph); C-NMR δ (ppm) (CDCl3): 20.7
(CH3CO), 22.6 (CH3CO), 38.9 (C-6), 55.4 (OCH3), 67.7 (C-5), 69.7 (C-3), 69.9 (C-2), 70.9 (C-4), 96.6
(C-1), 112.2 (Ph), 114.1 (Ph), 127.4 (Ph), 132.9 (Ph), 148.8 (Ph), 169.7 (C=O), 170.0 (CH3CO), 170.1
(CH3CO), 170.2 (CH3CO); ESI-TOF-MS: [M+1]+ m/z 439.1; [M+Na]+ m/z 461.1.
Methyl-6-(o-amino)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-galactopyranoside (4b). Yield: 78.0%;
1
mp: 78-80 ºC; []D +28o (c 1.01, CHCl3); H-NMR δ (ppm) (CDCl3): 2.00 (s, 3H, Ac), 2.10 (s, 3H,
Ac), 2.20 (s, 3H, Ac), 3.39 (s, 3H, OCH3), 3.44 (t, 1H, J 6.6 Hz, H-5), 3.60 (dd, 1H, J5,6e 6.9 Hz, J6a,6e
13.5 Hz, H-6e), 4.15 (dd, 1H, J5,6a 6.9 Hz, J6a, 6e 13.5 Hz, H-6a), 5.00 (d, 1H, J1, 2 3.6 Hz, H-1), 5.18
(dd, 1H, J1,2 3.6 Hz, J2,3 10.8 Hz, H-2), 5.37 (dd, 1H, J3,4 3.3 Hz, J2,3 10.8 Hz, H-3), 5.45 (d, 1H, J 3.3
13
Hz, H-4), 6.49 (t, 1H, J 6.3 Hz, H-NH), 6.63-7.33 (m, 4H, Ph); C-NMR δ (ppm) (CDCl3): 20.6
(CH3CO),20.7 (CH3CO), 20.8 (CH3CO), 38.8 (C-6), 55.0 (OCH3), 66.7 (C-5), 67.5 (C-3), 68.3 (C-2),
69.4 (C-4), 97.2 (C-1), 115.2 (Ph), 116.7 (Ph), 117.4 (Ph), 127.0 (Ph), 132.5 (Ph), 148.9 (Ph), 169.2
(C=O), 169.8 (CH3CO) , 170.5 (CH3CO), 171.0 (CH3CO); ESI-TOF-MS: [M+1]+ m/z 439.1; [M+Na]+
m/z 461.1.
Methyl-6-(o-amino)benzamidyl-6-deoxy-2,3,4-tri-O-acetyl-α-D-mannopyranoside (4c). Yield: 77.6%;
mp: 150-154 ºC; []D +40o (c 1.10, CHCl3); 1H-NMR δ (ppm) (CDCl3): 2.00 (s, 3H, Ac), 2.10 (s, 3H,
Ac), 2.12 (s, 3H, Ac), 3.37 (s, 3H, OCH3), 3.40 (m, 1H, H-6e), 3.85-3.98 (m, 2H, H-5, 6a), 4.70 (s, 1H,
H-1), 5.19-5.25 (m, 2H, H-2, 4), 5.36 (dd, 1H, J3,2 3.3 Hz, J3,4 10.8 Hz, H-3), 6.56 (t, 1H, J 5.4 Hz, H-
13
NH), 6.63-7.37 (m, 4H, Ph); C-NMR δ (ppm) (CDCl3): 20.7 (CH3CO), 20.8 (CH3CO), 39.3 (C-6),
55.3 (OCH3), 67.1 (C-4), 68.8 (C-5), 68.9 (C-3), 69.6 (C-2), 98.4 (C-1), 115.8 (Ph), 116.5 (Ph), 117.3
(Ph), 126.9 (Ph), 132.4 (Ph), 148.8 (Ph), 169.2(C=O), 169.9 (CH3CO), 170.0 (CH3CO), 170.3
(CH3CO); ESI-TOF-MS: [M+1]+ m/z 439.1; [M+Na]+ m/z 461.1.