´
C. Satge et al. / Tetrahedron 61 (2005) 8405–8409
8407
1
10.7 Hz, H-5b), 2.08 (m, 9H, acetyls). 13C NMR: d 170.0, 169.9
(carbonyls), 87.7 (C-1), 71.0 (C-2), 69.7 (C-3), 68.2 (C-4), 62.7
(C-5), 20.9, 20.8 (2) (acetyls). ESHRMS: calcd for C11H15O7-
BrNaC: 360.9899; found: 360.9897. Due to the instability of the
product, it should be noted that this signal was not always
observed.
ether/EtOAc). IR (KBr): n 2956, 1747. H NMR (CDCl3):
d 5.45 (t, 0.44H, J2,3,4Z9.8 Hz, H-3a), 5.17 (m, 0.56H,
H-1a, H-3b), 4.96 (m, 1.56H, H-4a, H-2b, H-4b), 4.77 (dd,
0.44H, J1,2Z3.9 Hz, J2,3Z10.3 Hz, H-2a), 4.52 (d, 0.56H,
J1,2Z7.4 Hz, H-1b), 4.14 (dd, 0.56H, J5a,4Z5.5 Hz,
J5a,5bZ11.8 Hz, H-5ab), 3.75 (m, 0.88H, H-5a), 3.38 (dt,
0
0
0
0
0
0
0.44H, J1 ,6 Z4.0 Hz, J6 ,1 ,2 Z10.6 Hz, H-1 a), 3.33 (m,
0.56H, H-5bb), 3.30 (m, 0.56H, H-10b), 2.24 (m, 0.44H,
H-70a), 2.15 (m, 0.56H, H-60ab), 2.08 (m, 0.56H, H-70b),
2.05 (m, 190.8H, acetyls), 1.84 (m, 0.44H, H-600aa), 1.65 (m,
0.88H, H-4 0aa, H-30aa), 1.63 (m, 0.560H, H-4 ab), 1.61 (m,
0.56H, H-3 ab), 1.37 (m, 0.56H, H-5 b), 1.35 (m, 0.44H,
H-20a), 1.30 (m, 0.44H, H-50a), 1.22 (m, 0.56H, H-20b),
4.2. General method for xylosylation
2,3,4-Triacetyl-1-bromo-a-D-xylopyranose (0.6 mmol) and
alcohol (1.5 mmol) were dissolved in anhydrous DMF
(1.0 mL) and kept under Ar at 50 8C for 16 h. EtOAc
(20 mL) was added and the organic layer was washed with
saturated NaHCO3 (20 mL) and water (20 mL), then dried
over MgSO4. The mixture was filtered, CH2Cl2 (5 mL) and
pyridine (2.2 mmol, 0.18 mL) were added. ClCOCH3
(1.8 mmol, 0.13 mL) was added dropwise at 0 8C and the
mixture was stirred for 1 h. CH2Cl2 (5 mL) was added, the
mixture was successively washed with water (10 mL), HCl
2 M (2!10 mL), saturated aq. NaHCO3 (10 mL) and water
(10 mL). The organic phase was dried over MgSO4, filtered,
then purified by silica gel column chromatography (9:1 then
4:1 petroleum ether/EtOAc). The products were obtained as
a mixture of two anomers.
1.06 (m, 0.56H, H-60bb), 0.95 (d, 1.32H, J7 ,8 Z7.0 Hz,
H-80a), 0.94 (m, 1H, H-30b), 0.89 (m, 3H, H-100), 0.88 (m,
1.68H, H-800b), 0.83 (m, 0.44H, H-40ba), 0.80 (m, 1H,
0
0
H-60ba, H-4 bb), 0.77 (d, 1.32H, J7,9Z7.0 Hz, H-90a), 0.75
(d, 1.68H, J7 ,9 Z7.1 Hz, H-9 b). 13C NMR: d 170.3 (2),
170.0 (2), 169.8, 169.3 (carbonyls), 102.3 (C-1b), 92.6
(C-1a), 82.3 (C-10b), 77.3 (C-10a), 72.1 (C-3b), 71.5
(C-2b), 71.1 (C-2a), 69.5 (2) (C-3a, C-4a), 69.0 (C-4b),
62.20(C-5b), 58.6 (C-5a), 48.2 (C-20b), 47.4 (C-20a), 43.0
(C-60b), 40.0 (C-60a), 34.2 (C-40a), 34.1 (C-40b), 31.6
(C-5 b), 31.2(C-50a),25.3(C-70a),24.9(C-70b),22.70(C-30b),
22.50(C-30a), 22.2 (C-100b), 22.1 (C-100a), 21.1 (C-80 a), 21.0
(C-8 b), 20.8 (3), 20.7 (2), 20.5 (acetyls), 15.8 (C-9 b), 14.9
(C-90a). ESHRMS: calcd for C21H34O8NaC: 437.2151;
found: 437.2148.
0
0
0
4.2.1. (30S)-30,70-Dimethyloct-60-enyl 2,3,4-triacetyl-D-
xylopyranoside (2). Colourless oil. YieldZ53%; a/bZ
41/59. Rfa 0.45; Rfb 0.34 (4:1 petroleum ether/EtOAc). IR
1
(KBr): n 2927, 1755. H NMR (CDCl3): d 5.48 (t, 0.41H,
J2,3,4Z9.7 Hz, H-3a), 5.16 (t, 0.59H, J2,3,4Z8.5 Hz, H-3b),
5.09 (m, 1H, H-60), 4.99 (m, 0.41H, H-1a), 4.94 (m, 1.59H,
H-4a, H-2b, H-4b), 4.79 (dd, 0.41H, J2,1Z3.4 Hz, J2,3
Z
9.9 Hz, H-2a), 4.47 (d, 0.59H, J1,2Z6.9 Hz, H-1b), 4.12
(dd, 0.59H, J4,5aZ5.1 Hz, J5a,5bZ11.8 Hz, H-5ab), 3.87 (m,
0.59H, H-10ab), 3.77 (m, 0.41H, H-5aa), 3.73 (m, 0.82H,
H-100aa, H-5ba), 3.49 (m, 0.59H, H-10bb), 3.44 (m, 0.41H,
H-1 ba), 3.37 (m, 0.59H, H-5bb), 2.05 (m, 9H, acetyls),
2.04 (m, 1H, H-500a), 1.68 (s, 3H, H-800), 1.66 (m, 1H, H-2a0),
1.60 (m, 3H, H-9 ), 1.55 (m, 1H, H-3 ), 1.41 (m, 1H, H-20b),
1.34 (m, 1H, H-40a), 1.21 (m, 1H, H-50b), 1.16 (m, 1H,
H-40b), 0.88 (m, 3H, H-100). 13C NMR: d 170.4, 170.03,
170.2, 170.1, 170.0, 169.5 (carbonyls), 131.4, 131.3 (C-7 ),
124.8, 124.7 (C-60), 100.9 (C-1b), 95.7 (C-1a), 71.7 (C-3b),
71.3 (C-2a), 71.00 (C-2b), 69.9 (C-3a), 69.6 (C-4a), 69.1
(C-4b), 68.1 (C-1 b), 66.9 (C-10a), 62.1 (C-5b), 58.4 (C-
5a), 37.2 (2) (C-40), 36.5, 36.3 (C-20), 29.7, 29.4 (C-30), 25.8
(C-80), 25.6, 25.5 (C-50), 20.7 (4), 20.6 (2) (acetyls), 19.6,
19.4 (C-100), 17.7 (C-90). ESHRMS: calcd for
C21H34O8NaC: 437.2151; found: 437.2159.
4.2.3. (10S,20S,40S)-10,70,70-Trimethylbicyclo[2.2.1]hept-
20-yl 2,3,4-triacetyl-D-xylopyranoside (4). White paste.
YieldZ42%; a/bZ34/66. Rfa 0.42; Rfb 0.32 (4:1 pet-
1
roleum ether/EtOAc). IR (KBr): n 2953, 1751. H NMR
(CDCl3): d 5.50 (t, 0.34H, J2,3,4Z9.8 Hz, H-3a), 5.16 (t,
0.66H, J2,3,4Z8.5 Hz, H-3b), 5.04 (d, 0.34H, J1,2Z3.7 Hz,
H-1a), 4.94 (m, 1.66H, H-4a, H-2b, H-4b), 4.76 (dd, 0.34H,
J1,2Z3.7 Hz, J2,3Z10.1 Hz, H-2a), 4.47 (d, 0.66H, J1,2
Z
Z
6.7 Hz, H-1b), 4.12 (dd, 0.66H, J4,5aZ4.9 Hz, J5a,5b
0
0
0
11.7 Hz, H-5ab), 3.99 (d, 0.66H, J2 ,3 Z8.8 Hz, H-2 b), 3.76
(dd, 0.34H, J4,5aZ6.1 Hz, J5a,5bZ10.6 Hz, H-5aa), 3.76 (m,
0.34H, H-20a), 3.69 (t, 0.34H, J4,5b,5aZ10.8 Hz, H-5ba),
3.34 (dd, 0.66H, J4,5bZ8.9 Hz, J5a,5bZ11.8 Hz, H-5bb),
2.18 (m, 0.34H, H-30aa), 2.13 (m, 0.66H, H-30ab), 2.10 (m,
0.34H, H-60aa), 2.08 (m, 09H, acetyls), 1.90 (m, 0.34H,
H-60ba), 1.72 (m, 2H, H-5 ), 1.66 (m, 1H, H-40), 1.20 (m,
1.32H, H-60b), 1.11 (m, 0.34H, H-30ba), 0.91 (m, 0.66H,
H-30bb), 0.86 (s, 01.98H0, H-100b), 0.85 (s, 1.98H, H-80b),
0.84 (2s, 3H, H-8 a H-9 b), 0.83 (s, 1.02H, H-90a), 0.80 (s,
1.02H, H-100a). 13C NMR: d 170.5, 170.3 (2), 170.2, 170.0,
169.4 (carbonyls), 99.1 (C-1b), 97.2 (C-1a), 85.5 (C-20a),
82.7 (C-20b), 71.5 (C-2a), 71.4 (C-3b), 70.9 (C-2b), 69.9
(C-3a), 69.8 (C-4a), 690.0 (C-4b), 62.0 (C-5b), 58.6 (C-5a),
49.7 (C-70a), 49.1 (C-7 b), 48.0 (C-10b), 47.8 (C-10a), 45.1
4.2.2. (10S,20R,50S)-20-(Prop-2-yl)-50-methylcyclohexyl 2,
3,4-triacetyl-D-xylopyranoside (3). White paste. YieldZ
45%; a/bZ44/56. Rfa 0.49; Rfb 0.39 (4:1 petroleum