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refluxed for 5 h. Reaction mass was filtered on Whatman filter
paper and the filtrate was concentrated. Crude mass thus obtained
was purified over silica gel CC in MeOH: CHCl3 (0e8%) to furnish
white solid 3 (m.p. 136e138 ꢂC, 24 mg). 1H NMR (300 MHz, CD3OD)
dH 3.48 (3H, m, H-20, 30, 40), 3.70 (3H, s, OCH3), 3.74 (1H, m, H-50),
4.44e4.55(2H, m, H-60), 4.67e4.76 (3H, m, H-10, 7), 6.47 (1H, dd,
J ¼ 2.9, 8.8 Hz, H-4), 6.89 (1H, d, J ¼ 2.8 Hz, H-6), 7.07 (1H, d,
J ¼ 8.8 Hz, H-3), 7.49 (2H, t, J ¼ 7.7 Hz, H-300), 7.63 (1H, t, J ¼ 7.3 Hz,
H-400), 8.04 (2H, d, J ¼ 7.1 Hz, H-200); 13C NMR (75 MHz, CD3OD) dC
56.0 (OCH3), 60.8 (C-7), 65.3 (C-60), 72.0 (C-40), 75.0 (C-20), 75.6 (C-
50), 78.0 (C-30), 104.2 (C-10), 114.0 (C-4), 115.0 (C-6), 119.2 (C-3),
129.6 (C-300), 130.6 (C-200), 131.3 (C-100), 134.0 (C-1), 134.3 (C-40þ0),
150.5 (C-2), 156.8 (C-5), 167.7 (C-700); ESIMS m/z 443 [MþNa] ;
Anal. Calcd for C21H24O9: C, 59.99; H, 5.75; Found: C, 59.64; H, 5.68.
CD3OD) dC 14.4 (OCH2CH3), 18.8 (OCH(CH3)CO), 60.7 (C-7), 62.3
(OCH2CH3), 65.3 (C-60), 72.0 (C-40), 74.3 (OCH(CH3)CO), 75.0 (C-20),
75.6 (C-50), 78.0 (C-30), 104.1 (C-10), 114.1 (C-4), 115.4 (C-6), 119.0 (C-
3), 129.7 (C-300), 130.6 (C-200), 131.3 (C-100), 134.1 (C-1), 134.4 (C-400),
151.2 (C-2), 154.6 (C-5), 166.9 (C-700), 171.1 (OCH(CH3)CO); ESIMS m/
z 529 [MþNa]þ; Anal. Calcd for C25H30O11: C, 59.28; H, 5.97; Found:
C, 59.18; H, 5.92.
4.2.4.3. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-(2-tert-butoxy-2-
oxoethoxy)benzyl alcohol (7). Gum; yield 0.37 equiv; 1H NMR
(300 MHz, CD3OD) dH 1.47 (9H, s, 3CH3), 3.49 (3H, m, H-20, 30, 40),
3.73 (1H, m, H-50), 4.46 (2H, s, OCH2CO), 4.54e4.76 (5H, m, H-10, 60,
7), 6.49 (1H, dd, J ¼ 2.8, 8.8 Hz, H-4), 6.91 (1H, d, J ¼ 2.7 Hz, H-6),
7.08 (1H, d, J ¼ 8.8 Hz, H-3), 7.51 (2H, m, H-300), 7.64 (1H, m, H-400),
8.05 (2H, d, J ¼ 7.8 Hz, H-200); ESIMS m/z 543 [MþNa]þ; Anal. Calcd
for C26H32O11: C, 59.99; H, 6.20; Found: C, 60.97; H, 6.88.
4.2.3. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-ethoxybenzyl alcohol
(4)
A mixture of 1 (30 mg, 0.07 mmol), (C2H5)2SO4 (0.014 mL,
0.11 mmol) and anhyd. K2CO3 (20 mg, 0.14 mmol) in dry CH3CN
(10 mL) was refluxed for 16 h. On completion of the reaction, same
procedure followed as done for 3, to furnish white solid 4 (8 mg;
m.p. 132e134 ꢂC). 1H NMR (300 MHz, CD3OD) dH 1.34 (3H, t,
J ¼ 6.9 Hz, CH3), 3.49 (3H, m, H-20, 30, 40), 3.72 (1H, m, H-50), 3.91
(2H, q, J ¼ 6.9 Hz, OCH2CH3), 4.44e4.76 (5H, m, H-10, 60, 7), 6.47(1H,
dd, J ¼ 2.8, 8.8 Hz, H-4), 6.88 (1H, d, J ¼ 2.5 Hz, H-6), 7.06 (1H, d,
J ¼ 8.8 Hz, H-3), 7.49 (2H, t, J ¼ 7.7 Hz, H-300), 7.63 (1H, t, J ¼ 7.3 Hz,
H-400), 8.04 (2H, d, J ¼ 7.1 Hz, H-200); ESIMS m/z 457 [MþNa]þ; Anal.
Calcd for C22H26O9: C, 60.82; H, 6.03; Found: C, 60.52; H, 6.12.
4.2.4.4. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-(2-oxo-2-
phenylethoxy)benzyl alcohol (8). White solid; yield 0.68 equiv; m.p.
138e140 ꢂC; 1H NMR (300 MHz, DMSO-d6 þ D2O) dH 3.28 (3H, m,
H-20, 30, 40), 3.73 (1H, m, H-50), 4.27e4.60 (4H, m, H-60, 7), 4.69 (1H,
d, J ¼ 6.7 Hz, H-10), 5.40 (2H, s, OCH2COPh), 6.35 (1H, dd, J ¼ 2.8,
8.8 Hz, H-4), 6.92 (2H, m, H-3, 6), 7.45 (3H, m, Phenyl), 7.58 (2H, t,
J ¼ 7.6 Hz, H-300), 7.71(1H, t, J ¼ 7.2 Hz, H-400), 7.94 (2H, d, J ¼ 6.2 Hz,
Phenyl), 7.99 (2H, d, J ¼ 7.6 Hz, H-200); ESIMS m/z 542 [MþNH4]þ;
Anal. Calcd for C28H28O10: C, 64.12; H, 5.38; Found: C, 63.78; H, 5.12.
4. 2. 4. 5. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-(2-(4-
methoxyphenyl)-2-oxoethoxy)benzyl alcohol (9). White solid; yield
0.57 equiv; m.p. 134e136 ꢂC; 1H NMR (300 MHz, DMSO-d6 þ D2O)
dH 3.30 (3H, m, H-20, 30, 40), 3.68 (1H, m, H-50), 3.84 (3H, s, OCH3),
4.27e4.59 (4H, m, H-60, 7), 4.68 (1H, d, J ¼ 6.7 Hz, H-10), 5.32 (2H, s,
OCH2COPh), 6.33(1H, dd, J ¼ 2.8, 8.8 Hz, H-4), 6.92 (2H, m, H-3, 6),
7.10 (2H, d, J ¼ 8.7 Hz, 4-methoxyphenyl), 7.46 (3H, m, H-300, 400),
7.94 (2H, d, J ¼ 7.2 Hz, 4-methoxyphenyl), 7.98 (2H, d, J ¼ 8.8 Hz, H-
200); ESIMS m/z 572 [MþNH4]þ; Anal. Calcd for C29H30O11: C, 62.81;
H, 5.45; Found: C, 62.68; H, 5.39.
4.2.4. General procedure for the synthesis of 5-ether derivatives
(5e15)
A mixture of 1 (1 equiv), respective 2-bromo compound
(1.5e2.0 equiv), and anhyd. K2CO3 (1.5e2.0 equiv) in dry CH3CN
(10 mL) were refluxed for 4e5 h, till the completion of the reaction
as monitored by TLC. The reaction mass was filtered on Whatman
filter paper and the filtrate was concentrated under vacuum to
dryness. The crude mass thus obtained was subjected to CC over
silica gel eluted with gradient of MeOH: CHCl3 (0e10%) to obtain
pure compounds in quantitative yields.
4.2.4.6. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-(2-oxo-2-p-tolyle-
thoxy)benzyl alcohol (10). White solid; yield 0.74 equiv; m.p.
136e138 ꢂC; 1H NMR (300 MHz, DMSO-d6 þ D2O) dH 2.38 (3H, s,
CH3), 3.28 (3H, m, H-20, 30, 40), 3.67 (1H, m, H-50), 4.27e4.58 (4H, m,
H-60, 7), 4.68 (1H, d, J ¼ 6.8 Hz, H-10), 5.34 (2H, s, OCH2COPh), 6.31
(1H, dd, J ¼ 2.8, 8.8 Hz, H-4), 6.91 (2H, m, H-3, 6), 7.39 (2H, d,
J ¼ 8.2 Hz, p-tolyl), 7.44 (3H, m, H-300, 400), 7.88 (2H, d, J ¼ 8.1 Hz, p-
tolyl), 7.93 (2H, d, J ¼ 7.7 Hz, H-200); ESIMS m/z 556 [MþNH4]þ; Anal.
Calcd for C29H30O10: C, 64.68; H, 5.61; Found: C, 64.55; H, 5.49.
4.2.4.1. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-(2-ethoxy-2-
oxoethoxy) benzyl alcohol (5). White solid; yield 0.52 equiv; m.p.
126e128 ꢂC; 1H NMR (300 MHz, CD3OD) dH 1.26 (3H, t, J ¼ 7.1 Hz,
OCH2CH3), 3.50 (3H, m, H-20, 30, 40), 3.73 (1H, m, H-50), 4.21 (2H, q,
J ¼ 7.1 Hz, OCH2CH3), 4.47 (2H, m, H-60), 4.57 (2H, s, OCH2CO),
4.67e4.75 (3H, m, H-10, 7), 6.50 (1H, dd, J ¼ 2.9, 8.8 Hz, H-4), 6.93
(1H, d, J ¼ 2.8 Hz, H-6), 7.07 (1H, d, J ¼ 8.9 Hz, H-3), 7.49 (2H, t,
J ¼ 7.7 Hz, H-300), 7.63 (1H, t, J ¼ 7.3 Hz, H-400), 8.04 (2H, d, J ¼ 7.1 Hz,
H-200); 13C NMR (75 MHz, CD3OD) dC 14.4 (OCH2CH3), 60.6 (C-7),
62.3 (OCH2CH3), 65.2 (C-60), 66.7 (OCH2CO), 71.9 (C-40), 75.0 (C-20),
75.5 (C-50), 77.9 (C-30), 103.9 (C-10), 114.8 (C-4), 115.8 (C-6), 118.9 (C-
3), 129.6 (C-300), 130.6 (C-200), 131.3 (C-100), 134.1 (C-1), 134.3 (C-400),
151.1 (C-2), 155.0 (C-5), 167.7 (C-700), 171.0 (OCH2CO); ESIMS m/z 510
[MþNH4]þ; Anal. Calcd for C24H28O11: C, 58.53; H, 5.73; Found: C,
58.48; H, 5.65.
4.2.4.7. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-(2-(4-chlorophenyl)-
2-oxoethoxy)benzyl alcohol (11). White solid; yield 0.54 equiv; m.p.
144e146 ꢂC; 1H NMR (300 MHz, DMSO-d6 þ D2O) dH 3.29 (3H, m,
H-20, 30, 40), 3.73 (1H, m, H-50), 4.27e4.60 (4H, m, H-60, 7), 4.69 (1H,
d, J ¼ 6.9 Hz, H-10), 5.39 (2H, s, OCH2COPh), 6.37 (1H, dd, J ¼ 2.6,
8.7 Hz, H-4), 6.94 (2H, m, H-3, 6), 7.47 (3H, m, H-300, 400), 7.65 (2H, d,
J ¼ 8.5 Hz, 4-chlorophenyl), 7.94 (2H, d, J ¼ 6.7 Hz, H-200), 8.00 (2H,
d, J ¼ 8.5 Hz, 4-chlorophenyl); ESIMS m/z 576 [MþNH4]þ; Anal.
Calcd for C28H27ClO10: C, 60.17; H, 4.87; Found: C, 60.02; H, 4.49.
4.2.4.2. 2-(6-Benzoyl-
oxopropan-2-yloxy)benzyl
b
-glucopyranosyloxy)-5-(1-ethoxy-1-
alcohol (6). White solid; yield
0.32 equiv; m.p. 120e122 ꢂC; 1H NMR (300 MHz, CD3OD) dH 1.21
(3H, t, J ¼ 7.2 Hz, OCH2CH3), 1.54 (3H, d, J ¼ 6.8 Hz, OCH(CH3)CO),
3.48 (3H, m, H-20, 30, 40), 3.73 (1H, m, H-50), 4.15 (2H, q, J ¼ 7.1 Hz,
OCH2CH3), 4.46 (2H, m, H-60), 4.68e4.77 (4H, m, H-10, 7, OCH(CH3)
CO), 6.49 (1H, dd, J ¼ 2.8, 8.8 Hz, H-4), 6.90 (1H, d, J ¼ 2.8 Hz, H-6),
7.08 (1H, d, J ¼ 8.8 Hz, H-3), 7.51 (2H, t, J ¼ 7.4 Hz, H-300), 7.65 (1H, t,
J ¼ 7.1 Hz, H-400), 8.05 (2H, d, J ¼ 7.7 Hz, H-200); 13C NMR (75 MHz,
4.2.4.8. 2-(6-Benzoyl-b-glucopyranosyloxy)-5-benzyloxybenzyl
alcohol (12). White solid; yield 0.41 equiv; m.p. 128e130 ꢂC; 1H
NMR (300 MHz, CD3OD): dH 3.51 (3H, m, H-20, 30, 40), 3.72 (1H, m, H-
50), 4.43e4.76 (5H, m, H-10, 60, 7), 4.96 (2H, s, OCH2Ph), 6.54 (1H, dd,
J ¼ 2.8, 8.8 Hz, H-4), 6.98 (1H, d, J ¼ 2.8 Hz, H-6), 7.06 (1H, d,
J ¼ 8.8 Hz, H-3), 7.28e7.40 (5H, m, Phenyl), 7.45 (2H, t, J ¼ 7.7 Hz, H-
300), 7.60 (1H, t, J ¼ 7.3 Hz, H-400), 8.03 (2H, d, J ¼ 7.2 Hz, H-200); ESIMS