MW Irradiation in Thioglycoside Synthesis
2781
anal. calcd. for C19H22N2O11S: C, 46.91; H, 4.56; N, 5.76. Found: C, 46.85; H,
4.63; N, 5.76.
(5-Nitropyrid-2-yl) 2-acetamido-30,40,60-tri-O-acetyl-20-deoxy-10-thio-b-
D-glucopyanoside (21). The crude product was recrystallized from
methanol to give 21 as pale yellow crystals, mp 225–2278C; 1H NMR
(CDCl3, 500 MHz) d: 1.91 (s, 3 H, NHAc), 2.03, 2.04, 2.05 (3 s, 9 H,
0
0
0
0
0
00
3 ꢀ OAc), 3.87 (4dd, 1 H, J5 ,4 ¼ 9.9 Hz, J5 ,6 ¼ 1.8 Hz, J5 ,6 ¼ 4.6 Hz,
H-50), 4.09 (dd, 1H, J6 ,5 ¼ 1.8 Hz, J6 ,6 ¼ 13.0 Hz, H-60), 4.26 (dd, 1 H,
0
0
0
00
J6 ,5 ¼ 4.6 Hz, J6 ,6 ¼ 13.0 Hz, H-600), 4.43 (q, 1 H, J2 ,1 ¼ 9.9 Hz,
00
0
00
0
0
0
J2 ,3 ¼ 9.9 Hz, H-20), 5.12 (dd, 1 H, J4 ,3 ¼ 9.9 Hz, J4 ,5 ¼ 9.2 Hz, H-40),
0
0
0
0
0
0
5.24 (t, 1 H, J3 ,4 ¼ 9.9 Hz, J3 ,2 ¼ 9.9 Hz, H-30), 5.85 (d,
1
H,
0
0
0
0
J1 ,2 ¼ 11.4 Hz, H-10), 6.03 (d, 1 H, J2 ,NH ¼ 9.2 Hz, NH), 7.32 (d, 1 H
J3,4 ¼ 9.2 Hz, H-3), 8.27 (dd, 1 H, J4,3 ¼ 9.2 Hz, J4,6 ¼ 3.1 Hz, H-4), 9.20
(d, 1 H, J6,5 ¼ 2.3 Hz, H-6); 13C NMR (CDCl3) d: 20.7, 20.8, 20.9 (CH3CO),
23.4 (NHAc), 52.4 (C-20), 62.0 (C-60), 68.0 (C-40), 73.9 (C-30), 76.4 (C-50),
82.5 (C-10), 122.5 (C-3), 131.2 (C-4), 141.9 (C-2), 144.9 (C-6), 164.6 (C-5),
169.3, 170.4, 170.7, 171.3 (4 ꢀ CH3CO); anal. calcd. for C19H23N3O11S: C,
47.01; H, 4.78; N, 8.66; S, 6.61. Found: C, 46.95; H, 4.76; N, 8.66; S, 6.73.
0
0
0
(3-Methylquinoxalin-2-yl) 20,30,40,60-tetra-O-acetyl-10-thio-b-D-glucopyr-
anoside (22). The crude product was stirred with water, filtered, and recrystal-
lized from methanol to give 22 as yellow crystals, mp 173–1758C; 1H NMR
(CDCl3, 500 MHz) d: 1.9, 2.03, 2.05, 2.09 (4 s, 12 H, 4 ꢀ OAc), 2.65 (s, 3 H,
CH3), 4.06 (dddd, 1 H, J5 ,4 ¼ 9.9 Hz, J5 ,6 ¼ 2.3 Hz, J5 ,6 ¼ 4.6 Hz,H-50),
0
0
0
0
0
00
4.13 (dd, 1 H, J6 ,5 ¼ 2.3 Hz, J6 ,6 ¼ 12.3 Hz, H-60), 4.24 (dd, 1 H,
0
0
0
00
J6 ,5 ¼ 4.6 Hz, J6 ,6 ¼ 12.3 Hz, H-600), 5.20 (dd, 1 H, J4 ,3 ¼ 9.2 Hz,
00
0
00
0
0
0
J4 ,5 ¼ 9.9 Hz, H-40), 5.38 (dd, 1 H, J2 ,1 ¼ 10.7 Hz, J2 ,3 ¼ 9.2 Hz, H-20),
0
0
0
0
0
0
5.46 (t, 1 H, J3 ,2 ¼ J3 ,4 ¼ 9.2 Hz, H-30), 6.10 (d, 1 H, J1 ,2 ¼ 10.7 Hz,
H-10), 7.63–7.69 (m, 2 H, H-6, H-7), 7.9 (dd, 1 H, J5,7 ¼ 1.5 Hz,
J5,6 ¼ 9.2 Hz, H-5), 7.97 (dd, 1 H, J6,8 ¼ 1.5 Hz, J7,8 ¼ 8.5 Hz, H-8); anal.
calcd. for C23H26N2O9S: C, 54.54; H, 5.17; N, 5.53; S, 6.33. Found: C,
54.00; H, 5.19; N, 5.41; S, 7.00.
0
0
0
0
0
0
(3-Methylquinoxalin-2-yl) 20-acetamido-30,40,60-tri-O-acetyl-20-deoxy-10-
thio-b-D-glucopyranside (23). The product obtained was recrystallized
1
from ether to give 23 as yellow crystals, mp 212–2148C; H NMR (CDCl3,
500 MHz) d: 1.88 (s, 3 H, NHAc), 1.94, 2.07, 2.09 (3 s, 9 H, 3 ꢀ OAc),
2.69 (s, 3 H, CH3), 3.95–3.97 (m, 1 H, H-50), 4.12 (dd, 1 H, J6 ,5 ¼ 2.3 Hz,
0
0
J6 ,6 ¼ 12.2 Hz, H-60), 4.22 (dd, 1 H, J6 ,5 ¼ 5.3 Hz, J6 ,6 ¼ 12.2 Hz,
0
00
00
0
00
0
H-600), 4.59 (dd, 1 H, J2 ,NH ¼ 9.9 Hz, J2 ,3 ¼ 9.9 Hz, H-20), 5.22 (dd, 1 H,
0
0
0
J4 ,3 ¼ 9.2 Hz, J4 ,5 ¼ 9.9 Hz, H-40), 5.29 (dd, 1 H, J3 ,2 ¼ 9.9 Hz,
0
0
0
0
0
0
J3 ,4 ¼ 9.2 Hz, H-30), 5.87 (d, 1 H, J2 ,NH ¼ 9.9 Hz, NH), 5.97 (d, 1 H,
0
0
0
J1 ,2 ¼ 10.7 Hz, H-10), 7.63–7.69 (m, 2 H, H-6, H-7), 7.89 (dd, 1 H,
0
0
J5,7 ¼ 1.5 Hz, J5,6 ¼ 8.4 Hz, H-5), 7.97 (dd,
1
H, J6,8 ¼ 1.5 Hz,