1
4
6
1
369, 1325, 1215, 1107, 1045, 939, 916, 866, 812, 748, 700, 634, 601, 570, 545, 495, 418,
1
05; H NMR (400 MHz, CDCl ): δ 9.24 (1H, s), 7.56 (1H, d, J = 7.8 Hz), 7.29-7.34 (5H, m),
3
.19 (1H, s), 5.66 (1H, d, J = 7.5 Hz), 5.43 (1H, d, J = 8.1 Hz), 5.17 (1H, s), 4.68 (2H, t, J =
2.0 Hz), 4.54 (1H, d, J = 11.3 Hz), 4.24 (1H, d, J = 7.8 Hz), 4.09 (1H, d, J = 9.6 Hz), 3.90
1
3
(
1H, s), 2.19 (3H, s), 2.08 (3H, s), 1.86 (3H, s); C NMR (100 MHz, CDCl ): δ 170.7, 169.8,
3
1
6
4
69.3, 162.9, 150.2, 140.1, 135.8, 129.0, 128.8, 128.6, 103.0, 88.8, 79.4, 79.3, 78.1, 71.6,
+
7.5, 62.6, 20.9, 20.8; HRMS (ESI): m/z calcd for C H N O [M+H] : 491.1660; found:
23
27
2
10
91.1671.
2
',5',6'-Tri-O-acetyl-3'-O-benzyl-β-D-glucofuranosyl thymine (14b)
It was obtained as white solid (1.02 g) in 89% yield. R = 0.24 (2% MeOH/chloroform);
f
2
4
-1
[
α]D = + 24.67 (c 0.1, MeOH); m/p: 118-120 °C; IR (KBr, cm ): 1741, 1691, 1460, 1371,
1
1
219, 1049, 746, 700, 592, 480; H NMR (400 MHz, CDCl ): δ 8.75 (1H, s), 7.30-7.36 (6H,
3
m), 6.24 (1H, d, J = 1.4 Hz), 5.47-5.51 (1H, m), 5.15 (1H, s), 4.71 (1H, d, J = 11.2 Hz), 4.66
(1H, dd, J = 12.5, 2.2 Hz), 4.55 (1H, d, J = 11.2 Hz), 4.23 (1H, dd, J = 9.2, 3.2 Hz), 4.10
(1H, dd, J = 12.5, 4.4 Hz), 3.91 (1H, d, J = 3.2 Hz), 2.19 (3H, s), 2.09 (3H, s), 1.94 (3H, s),
1
3
1
.68 (3H, s); C NMR (100 MHz, CDCl ): δ 170.7, 169.9, 169.4, 163.6, 150.4, 136.0, 135.9,
3
1
28.7, 128.6, 111.8, 88.4, 79.5, 79.0, 78.8, 71.8, 67.7, 62.7, 20.9, 20.9, 12.4; HRMS (ESI):
+
m/z calcd for C H N O [M+H] : 505.1817; found: 505.1831.
2
4
29
2
10
Synthesis of 3'-O-benzyl-β-D-glucofuranosyl pyrimidines nucleosides 15a-b.
To the stirred solution of compound 14a (1.2 g, 2.44 mmol) or 14b (1.2 g, 2.38 mmol ) in
methanol:water (9:1, 120 mL), K CO (1.01 g, 7.32 mmol for 14a) or (0.98 g, 7.14 mmol
2
3
for 14b) was added at 0 °C and the reaction mixture was kept under stirring at 25 °C for 1h.
On completion of the reaction, solvent was removed under reduced pressure. The residue thus
obtained was purified by column chromatography with a gradient solvent system of methanol
in chloroform to afford trihydroxy nucleosides 15a and 15b in quantitative yields.
3
'-O-Benzyl-β-
D-glucofuranosyl uracil (15a)
It was obtained as white solid (0.88 g) in 99% yield. R = 0.23 (10% MeOH/chloroform);
f
24
-1
[
α]D = + 45.13 (c 0.1, MeOH); m/p: 150-153 °C; IR (KBr, cm ): 3363, 3059, 2939, 1666,
1
1
462, 1394, 1261, 1207, 1070, 1043, 896, 813, 740, 698, 640, 572, 547; H NMR (400 MHz,
DMSO-d ): δ 11.30 (1H, s), 7.56 (1H, d, J = 8.1 Hz), 7.27-7.34 (5H, m), 5.87 (1H, d, J = 4.0
6
Hz), 5.67 (1H, s), 5.46 (1H, dd, J = 8.1, 2.2 Hz), 4.85 (1H, s), 4.60 (2H, q, J = 11.8 Hz), 4.52