the residue was directly subjected to silica column chromatography
and eluted with MeOH/CHCl3 = 0.5 : 9.5 to yield 10a (0.52 g, 62%)
as a white solid; Rf 0.5 (MeOH:CHCl3 = 1 : 9); mp = 192 ◦C; [a]D20
-10.2 (c 3.6, CH3OH); 1H NMR (500 MHz, CD3OD) d 7.63–7.21
(m, 10H, C6H5), 5.59 (s, 1H, CHPh), 4.64 (d, J = 9.8, 1H, H-1),
4.59 (d, J = 7.8, 1H, H-1¢), 4.32 (ddd, J = 10.3, 6.4, 3.2, 1H, H-6),
3.94 (dd, J = 12.3, 2.4, 1H, H-6¢), 3.88 (dd, J = 12.3, 4.2 Hz, 1H,
H-6¢), 3.83–3.77 (m, 1H, H-6), 3.70–3.44 (m, 6H, H-3, H-3¢, H-4,
H-4¢, H-5, H-5¢), 3.38–3.28 (m, 2H, H-2, H-2¢); 13C NMR (125
MHz, CD3OD) d 139.1, 134.9, 133.0, 129.9, 129.1, 128.5, 127.6
(2 ¥ C6H5), 105.1 (CHPh), 102.9 (C1¢), 89.1 (C-1), 82.0, 80.5,
80.3, 77.7, 75.8, 74.5, 73.6, 67.8 (C2, C2¢, C3, C3¢, C4, C4¢, C5,
C5¢), 69.5, 61.9 (C6, C6¢). HRMS-ES [M+Na]+: found 545.1463,
calculated 545.1560.
3H, COCH3), 1.96 (s, 3H, COCH3), 1.95 (s, 3H, COCH3), 1.90 (s,
3H, COCH3); 13C NMR (125 MHz, CDCl3) d 170.1, 169.4, 169.4,
169.3 (COCH3), 145.5, 136.6, 133.4, 132.9, 131.1, 130.2, 129.2,
128.9, 128.5, 128.3, 128.1, 126.1 (2 ¥ C6H5), 101.6 (CHPh), 101.1
(C1¢), 85.2 (C1), 77.9, 76.1, 75.6, 73.8, 72.5, 71.8, 69.8, 66.2 (C2,
C2¢, C3, C3¢, C4, C4¢, C5, C5¢), 68.4, 66.8 (C6, C6¢), 21.6, 20.9,
20.7 (s), 20.6 (CH3OPh, COCH3). HRMS-ES: found 844.6915,
calculated 844.6978
1-Thiophenyl-3,6-anhydro-4-O-(4¢,6¢-O-benzylidiene-b-D-
glucopyranosyl)-b-D-glucopyranoside (11a)
Compound 11 (150 mg, 0.22 mmol) was dissolved in DMF (10 mL)
and to it was added potassium-t-butoxide (37 mg, 0.33 mmol) at
rt. After stirring for 2 h the reaction was quenched with saturated
NH4Cl solution (10 mL). DMF was then removed under vacuo,
and the residue was extracted with water (30 mL) and CHCl3 (2
¥ 30 mL) and the organic phase was concentrated in vacuo the
residue was loaded directly on silica. Elution with EtOAc/PE =
5 : 5 gave compound 11a (100 mg, 90%) as a sticky solid. Rf 0.5
(EtOAc); [a]2D0 -88.0 (c 2.17, CHCl3); 1H NMR (500 MHz, CDCl3)
d 7.47–7.14 (m, 10H, 2 ¥ C6H5), 5.49 (d, J = 2.0, 1H, H-1), 5.44 (s,
1H, CHPh), 4.79 (d, J = 10.4, 1H, H6), 4.55 (d, J = 7.7, 1H, H-1¢),
4.42 (t, J = 2.8, 1H, H-4), 4.34 (dd, J = 5.4, 2.8, 1H, H-5), 4.26
(dt, J = 7.8, 3.0, 2H, H-6¢, H-4¢), 3.97 (bd, 1H, H-2), 3.84–3.75
(m, 2H, H-3, H-6), 3.75–3.65 (m, J = 13.1, 9.6, 2H, H-3¢, H-6¢),
3.50–3.35 (m, 2H, H-2¢, H-5¢); 13C NMR (125 MHz, CDCl3) d
136.7, 135.1, 131.2, 129.4, 129.0, 128.4, 127.3, 126.3 (Ar-C), 102.2
(CHPh), 102.0 (C1¢), 87.5 (C-1), 87.5, 80.2, 74.6, 74.3, 73.1, 72.9,
72.8, 66.9 (C2, C2¢, C3, C3¢, C4, C4¢, C5, C5¢), 69.8, 68.4 (C6,
C6b¢). HRMS-ES [M+Na]+: found 527.1337, calculated 527.1454.
1-Thiophenyl-6-O-tosyl-4-O-(4¢,6¢-O-benzylidiene-b-D-
glucopyranosyl)-b-D-glucopyranoside (11)
1-Thiophenyl-4-O-(4¢,6¢-O-benzylidiene-b-D-glucopyrano-syl)-
b-D-gluco-pyranoside (10a, 0.25 g, 0.48 mmol) was dissolved in
pyridine (1 mL) at room temperature and then tosylchloride (0.13
g, 0.71 mmol) was added and the reaction mixture was stirred at
rt for 12 h. After completion of the reaction it was quenched with
NH4Cl, pyridine was then removed under vacuo and the reaction
mixture was extracted with water and EtOAc. The organic layer
was dried over Na2SO4 and concentrated in vacuo and the residue
was loaded on silica gel column and eluted with EtOAc/PE =
3 : 7 to yield compound 11 (0.24 g, 76%) as a sticky solid; Rf
1
0.7 (EtOAc); [a]2D0 -36.0 (c 0.2, CH3OH); H NMR (500 MHz,
CD3OD) d 7.55–7.26 (m, 15H, Ar-H), 5.58 (s, 1H, CHPh), 4.58–
4.49 (m, 2H), 4.38 (d, J = 7.9 Hz, 1H, H-1), 4.32 (dd, J = 10.8,
5.5 Hz, 1H), 4.27 (dd, J = 10.3, 4.9 Hz, 1H), 3.75 (t, J = 10.1 Hz,
1H), 3.70–3.63 (m, 1H), 3.59 (m, 2H), 3.55–3.40 (m, 4H), 3.22
(dd, J = 9.8, 8.5, 1H), 2.42 (s, 3H, C6H4OCH3); 13C NMR (125
MHz, CD3OD) d 146.5, 139.1, 134.4, 134.4, 133.5, 133.4, 131.2,
129.9, 129.8, 129.8, 129.2, 129.1, 128.6, 127.5 (Ar-C), 104.5 (C-1¢),
102.9 (CHPh), 88.6 (C-1), 81.9, 79.0, 77.3, 77.2, 75.3, 74.4, 73.2,
67.9 (C2, C2¢, C3, C3¢, C4, C4¢, C5, C5¢), 70.2, 69.4, (C6, C6¢),
21.6 (OCH3). HRMS-ES [M+Na]+: found 701.4867, calculated
701.4898.
1-Thiophenyl-2-O-acetyl-3,6-anhydro-4-O-(2¢,3¢-di-O-acetyl-4¢,6¢-
O-benzylidiene-b-D-glucopyranosyl)-b-D-glucopyranoside (13)
1-Thiophenyl-3,6-anhydro-4-O-(4¢,6¢-O-benzylidiene-b-D-gluco-
pyranosyl)-b-D-glucopyranoside (11a, 70 mg, 0.13 mmol) was
dissolved in pyridine (0.2 mL), Ac2O (0.07 mL, 0.69 mmol)
was then added and the reaction mixture was stirred at 25 ◦C
for 6 h. After completion of reaction the reaction mixture was
concentrated on vacuo and the residue was loaded directly on
silica. Elution with EtOAc/PE = 2.5 : 7.5 gave compound 13 (77
mg, 88%) as a semisolid. Rf 0.5 (EtOAc/PE = 5 : 5); [a]2D0 -9.25 (c
1-Thiophenyl-2,3-diacetyl-6-O-tosyl-4-O-(2¢,3¢di-O-acetyl-4¢,6¢-
O-benzylidiene-b-D-glucopyranosyl)-(1→4)-b-D-glucopyranoside
(12)
1
Compound 11 (202 mg, 0.29 mmol) was dissolved in pyridine
(0.5 mL), Ac2O (0.35 mL, 3.5 mmol) was then added, and the
reaction mixture was stirred at 25 ◦C for 6 h. After completion of
reaction, the reaction mixture was concentrated in vacuo to remove
Ac2O and pyridine The residue was loaded directly on silica and
elution with EtOAc/PE = 2.5 : 7.5 gave compound 12 (0.22 g,
88%) as a semisolid. Rf 0.5 (EtOAc/PE = 5 : 5); [a]2D0 -19.0 (c 1.6,
CHCl3); 1H NMR (500 MHz, CDCl3) d 8.16–7.08 (m, 15H), 5.38
(s, 1H, CHPh), 5.05 (t, J = 9.3, 2H, H-3, H-3¢), 4.78 (dd, J = 9.1,
7.9, 1H, H-2¢), 4.70 (t, J = 10.0 Hz, 1H, H-2), 4.52 (d, J = 10.1, 1H,
H-1), 4.34 (dd, J = 10.7, 1.9, 1H, H-6), 4.27 (d, J = 7.8, 1H, H-1¢),
4.24 (dd, J = 10.4, 5.0, 1H, H-6¢), 4.10 (dd, J = 10.7, 4.0, 1H, H-6),
3.70–3.50 (m, 3H, H-4, H-4¢, H-6¢), 3.50–3.44 (m, 1H, H-5), 3.26–
3.14 (td, J = 9.8, 5.0 Hz, 1H, H-5¢), 2.35 (s, 3H, CH3OPh), 1.99 (s,
6.2, CHCl3); H NMR (500 MHz, CDCl3) d 7.59–7.27 (m, 10H,
2 ¥ C6H5), 5.52 (s, 1H, CHPh), 5.36 (t, J = 9.5, 1H, H-3¢), 5.29
(d, J = 4.1, 1H, H-1), 5.09 (dd, J = 9.4, 7.9, 1H, H-2¢), 5.04 (dd,
J = 3.9, 2.5, 1H, H-2), 4.81 (d, J = 7.8, 1H, H-1¢), 4.47 (m, 2H,
H-5, H-6), 4.42–4.32 (m, 2H, H-3, H-6¢), 4.29 (dd, J = 5.5, 2.4,
1H, H-4), 3.88 (dd, J = 10.3, 2.6, 1H, H-6), 3.80 (t, J = 10.3, 1H,
H-6¢), 3.73 (t, J = 9.6, 1H, H-4¢), 3.57 (td, J = 9.7, 5.0, 1H, H-5¢),
2.12 (s, 3H, COCH3), 2.06 (s, 3H, COCH3), 1.91 (s, 3H, COCH3);
13C NMR (125 MHz, CDCl3) d 170.1, 169.9, 169.4 (COCH3),
136.6, 133.7, 132.4, 132.1, 129.2, 128.9, 128.3, 127.8, 126.1 (2 ¥
C6H5), 101.5 (CHPh), 99.6 (C1¢), 82.1 (C-1), 78.3, 74.8, 74.2, 72.4,
71.9, 71.7, 71.6, 66.6 (C2, C2¢, C3, C3¢, C4, C4¢, C5, C5¢), 71.0,
68.4, (C6, C6b¢), 20.9, 20.7, 20.4 (COCH3). HRMS-ES [M+Na]+:
found 653.1711, calculated 653.1771.
7532 | Org. Biomol. Chem., 2011, 9, 7525–7534
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