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Helvetica Chimica Acta Vol. 86 (2003)
(dd, 2J 12.1, 3J(6',7'b) 5.2, HbÀC(7')); 3.61 (dd, 3J(2,3) 9.3, 3J(1,2) 1.3, HÀC(2)); 3.52 (dd, 3J(3',4') 9.0,
3J(2',3') 9.0, HÀC(3')); 3.39 (dd, 3J(4',5') 9.0, 3J(3',4') 9.0, HÀC(4')); 3.34 (dd, 3J(5',6') 9.0, 3J(4',5') 9.0,
HÀC(5')); 3.24 (ddd, 3J(5',6') 9.0, 3J(6',7'b) 5.2, 3J(6',7'a) 2.0, HÀC(6')); 3.23 (dd, 3J(2',3') 9.0, 3J(1',2')
0.8, HÀC(2')); 2.17 (m, HÀC(3)); 1.70 1.67 (m, CH2(4)). 13C-NMR (100.6 MHz, CD3OD): 103.2 (d, J 172,
C(1)); 81.4 (d, J 141, C(6')); 79.8 (d, J 143, C(4')); 79.6 (d, J 138, C(2')); 74.4 (d, J 155, C(5)); 73.5, 73.4
(2d, J 142, C(1'), C(2)); 71.1 (d, J 144, C(5')); 70.7 (d, J 144, C(3')); 69.1 (t, J 149, C(6)); 62.5( t, J 142,
C(7')); 39.7 (d, J 128, C(3)); 31.8 (t, J 128, C(4)). CI-MS (NH3): 340 (48, [M 18] ), 323 (39), 305(78), 160
(34), 143 (100), 127 (98), 81 (58).
2-O-Acetyl-1,6-anhydro-3,4-dideoxy-3-C-[(1R)-1,3,4,5,7-penta-O-acetyl-2,6-anhydro-d-glycero-d-gulo-
heptitol-1-C-yl]-b-d-arabino-hexopyranose (22). As described for 9 (second reaction), with 21 (47 mg,
0.14 mmol), Ac2O (0.6 ml), pyridine (2.4 ml), and DMAP (0.2 mg) (co-evaporation with toluene (5ml)
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25
25
25
twice): 70 mg (83%) of 22. White solid. M.p. 80 848. [a] À53, [a] À55, [a] À94, [a] À115
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435
405
(c 0.11, CHCl3). UV (MeCN): 191 (6400). IR (KBr): 2955, 1750, 1440, 1375, 1240, 1100, 1035, 980, 900.
1H-NMR (400 MHz, CDCl3): 5.39 (d, 3J(1,2) 1.4, HÀC(1)); 5.17 (dd, 3J(4',5') 9.3, J(3',4') 9.3, HÀC(4'));
3
5.05, 5.03 (2dd, 3J(3',4') 9.3, 3J(2',3') 9.3, 3J(5',6') 9.3, 3J(4',5') 9.3, HÀC(3'), HÀC(5')); 5.04
(dd, 3J(1',3) 8.0, J(1',2') 2.4, HÀC(1')); 4.75( dd, 3J(2,3) 10.2, J(1,2) 1.4, HÀC(2)); 4.57 (m, HÀC(5));
3
3
4.17 4.11 (m, CH2(7')); 3.85(br. d, 2J 7.1, HendoÀC(6)); 3.81 (dd, 2J 7.1, 3J(5,6exo) 4.3, HexoÀC(6)); 3.62
(ddd, 3J(5',6') 9.3, J(6',7'a) 6.3, J(6',7'b) 2.8, HÀC(6')); 3.60 (dd, 3J(2',3') 9.3, J(1',2') 2.4, HÀC(2'));
2.66 (dddd, 3J(3,4exo) 12.2, 3J(2,3) 10.2, 3J(1',3) 8.0, 3J(3,4endo) 5.8, HÀC(3)); 2.10, 2.08, 2.07, 2.04, 1.99,
1.97 (6s, HexoÀC(4), 6 MeCOO); 1.66 (ddd, 2J 13.6, 3J(3,4endo) 5.8, 3J(4endo,5) 1.5, HendoÀC(4)).
13C-NMR (100.6 MHz, CDCl3): 170.5, 170.3, 170.3, 170.1, 169.5, 169.5 (6s, COO); 99.2 (d, J 177, C(1)); 76.5,
76.2 (2d, J 143, J 147, C(2'), C(6')); 74.3 (d, J 154, C(4')); 73.6 (d, J 149, C(2)); 72.7 (d, J 158, C(5));
69.3, 68.5, 67.1 (3d, J 145, J 155, J 155, C(1'), C(3'), C(5')); 68.1 (t, J 150, C(6)); 62.7 (t, J 149, C(7'));
33.6 (d, J 132, C(3)); 30.1 (t, J 130, C(4)); 20.9 20.5(6 q, J 130, MeCOO). CI-MS (NH3): 592 (100, [M
3
3
3
18] ), 575 (6), 515 (5), 117 (5). Anal. calc. for C25H34O15 (574.53): C 52.26, H 5.96; found: C 52.32, H 5.99.
1,2,6-Tri-O-acetyl-3,4-dideoxy-3-C-[(1R)-1,3,4,5,7-penta-O-acetyl-2,6-anhydro-d-glycero-d-gulo-heptitol-1-
C-yl]-a-d-arabino-hexopyranose (23a/23b). To a soln. of 22 (50 mg, 0.09 mmol) in Ac2O (3.7 ml), cooled to 08
with stirring under Ar, 125 ml of a dil. triethylsilyl trifluoromethanesulfonate soln. (50 ml of TESOTf in 2.5ml
Ac2O) was added and the reaction followed by TLC (light petroleum ether/AcOEt 1:2) to completion
(generally 5 10 min). A sat. aq. NaHCO 3 soln. (10 ml) was then added and, after stirring at 08 for 30 min, the
aq. mixture was extracted with AcOEt (3 Â 15ml), the combined org. extract washed with sat. aq. NaHCO 3
soln. (20 ml) and then with brine (20 ml), dried (MgSO4), and evaporated. FC (silica gel, light petroleum ether/
AcOEt 1:2) afforded 58 mg (98%) of 23, 6 :1 mixture of a- and b-d-anomers 23a/23b. White solid. M.p. 64
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25
25
25
678. [a] 33, [a] 37, [a] 64, [a] 81 (c 0.16, CHCl3). UV (MeCN): final absorbance at
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435
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223 (1200). IR (KBr): 1745, 1440, 1370, 1230, 1035, 605. 1H-NMR (400 MHz, CDCl3): 23a: 6.00 (br. s, HÀC(1));
5.67 (dd, 3J(1',3) 10.5, 3J(1',2') 2.3, HÀC(1')); 5.19 (dd, 3J(4',5') 9.3, 3J(3',4') 9.3, HÀC(4')); 5.10
(dd, 3J(5',6') 9.3, 3J(4',5') 9.3, HÀC(5')); 5.01 (dd, 3J(3',4') 9.3, 3J(2',3') 9.3, HÀC(3')); 4.63 (br. s,
HÀC(2)); 4.22 (dd, 2J 12.3, 3J(6',7'a) 5.6, HaÀC(7')); 4.18 4.09 (m, HÀC(5), HaÀC(6), HbÀC(6),
HbÀC(7')); 3.65( dd, 3J(2',3') 9.3, 3J(1',2') 2.3, HÀC(2')); 3.59 (ddd, 3J(5',6') 9.3, 3J(6',7'a) 5.6,
3J(6',7'b) 2.4, HÀC(6')); 2.40 (m, HÀC(3)); 2.14, 2.13, 2.11, 2.11, 2.09, 2.04, 2.01, 2.00 (8s, 8 MeCOO); 1.95
(ddd, 2J 14.7, 3J(4ax,5) 11.8, 3J(3,4ax) 5.9, HaxÀC(4)); 1.56 (br. d, 2J 14.7, HeqÀC(4)); 23b: 6.09
(d, 3J(1,2) 2.5, HÀC(1)). 13C-NMR (100.6 MHz, CDCl3): 23a: 170.8, 170.5, 170.4, 170.3, 169.4, 169.3, 169.3,
168.6 (8s, COO); 91.4 (d, J 177, C(1)); 76.7 (d, J 140, C(6')); 76.2 (d, J 138, C(2')); 74.5( d, J 146, C(4'));
68.1 (d, J 154, C(5')); 67.4 (2d, J 148, J 148, C(1'), C(3')); 66.1 (t, J 148, C(6)); 65.7 (d, J 153, C(2));
65.3 (d, J 148, C(5)); 62.3 (t, J 149, C(7')); 35.8 (d, J 136, C(3)); 23.5( t, J 130, C(4)); 21.0 20.5(8 q, J
130, MeCOO); 23b: 89.8 (d, J 170, C(1)). CI-MS (NH3): 694 (100, [M 18] ), 617 (82), 117 (3). Anal. calc.
for C29H40O18 (676.62): C 51.46, H 5.96; found: C 51.31, H 6.04.
1,6-Anhydro-3-C-[(1R)-2,6-anhydro-3,4,5,7-tetra-O-benzyl-d-glycero-d-gulo-heptitol-1-C-yl]-3,4-dideoxy-
1',2-O-isopropylidene-b-d-arabino-hexopyranose (24). As described for 11, with 20 (59 mg, 0.09 mmol), 2,2-
dimethoxypropane (2.5ml), acetone (2.5ml), and TsOH (20 mg) (for 3.5h). Workup as described, with AcOEt
(10 ml), H2O (10 ml), AcOEt (3 Â 10 ml), sat. aq. NaHCO3 soln. (10 ml), and brine (10 ml), followed by FC:
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15mg (25%) of 24. White solid. M.p. 159 1618. [a] À13, [a] À18, [a] À28, [a] À31 (c 0.16,
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CHCl3). UV (MeCN): 208 (34150). IR (KBr): 2875, 1455, 1360, 1100, 1025, 750, 700. 1H-NMR (400 MHz,
CDCl3): 7.37 7.19 (m, 20 arom. H); 5.31 (s, HÀC(1)); 4.91 4.59 (m, 8 H, OCH2Ph); 4.44 (m, HÀC(5)); 4.03
(dd, 3J(1',3) 10.3, 3J(1',2') 2.3, HÀC(1')); 3.84 (dd, 3J(3',4') 9.4, 3J(2',3') 9.4, HÀC(3')); 3.73
(dd, 3J(2,3) 9.1, 3J(1,2) 1.0, HÀC(2)); 3.72 3.65( m, HÀC(4'), HendoÀC(6), HexoÀC(6), HaÀC(7'),