Regio- and Stereo-selective Synthesis of Peracetylated Carbohydrate Esters
1H, H-1), 5.27 (t, J=9.7 Hz, 1H, H-3), 5.14—5.04 (m,
2H, H-2, H-4), 4.24 (dd, J6-6'=12.4 Hz, J6-5=4.0 Hz,
1H, H-6), 4.10—4.03 (m, 2H, H-5, H-6'), 2.42—2.37
(m, 2H, aliphatic OCCH2C17H35), 2.06, 2.02, 2.00, 1.98
(4×s, 12H, CH3CO), 1.23 (s, 30H, aliphatic
OCCH2(CH2)15CH3); 0.87 (t, J=6.5 Hz, 3H, aliphatic
OCC16H32CH3); 13C NMR (CDCl3, 100.6 MHz) δ:
171.21 (C=O, OCCH2C17H35), 170.22, 169.80, 169.22,
169.02 (C=O, Ac), 89.21 (C-1), 70.45 (C-3), 70.39
(C-5), 69.84 (C-2), 68.49 (C-4), 62.11 (C-6), 35.05
(aliphatic OCCH2C17H35), 32.86—29.97 (aliphatic
OCCH2(CH2)15CH3), 23.71, 21.72, 21.61, 21.48
(CH3CO, Ac), 15.23 (aliphatic OCC16H32CH3). HRMS
calcd for C32H54O11Na (M+Na)+ 637.3621, found
637.3597.
J3-4=10.4 Hz, 1H, H-3), 5.07 (dd, J5-4=3.4 Hz, J4-3=
10.4 Hz, 1H, H-4), 4.16—4.11 (m, 2H, H-5, H-6),
4.09—4.03 (m, 1H, H-6'), 2.44—2.31 (m, 2H, aliphatic
OCCH2C17H35), 2.16, 2.04, 2.03, 1.99 (4×s, 12H,
CH3CO), 1.24 (s, 30H, aliphatic OCCH2(CH2)15CH3),
0.87 (t, J=6.8 Hz, 3H, aliphatic OCC16H32CH3); 13C
NMR (CDCl3, 100.6 MHz) δ: 171.43 (C = O,
OCCH2C17H35), 169.94, 169.76, 169.58, 168.91 (C=O,
Ac), 92.38 (C-1), 72.24 (C-3), 71.43 (C-5), 68.47 (C-2),
67.43 (C-4), 61.67 (C-6), 34.98 (aliphatic OCCH2C17-
H35), 32.87, 30.63—29.93 (aliphatic OCCH2(CH2)15-
CH3), 25.57, 23.71, 21.66, 21.57 (CH3CO, Ac), 15.21
(aliphatic OCC16H32CH3). HRMS calcd for C32H54-
O11Na (M+Na)+ 637.3621, found 637.3475.
O-(2,3,4,6-tetra-O-Acetyl-β-D-galactopyranosyl)-
(1 → 4)-2,3,6-tri-O-acetyl-α-D-glucopyranosyl stear-
ate 4c (α) Yield 17.7%; Rf 0.66 (cyclohexane/ethyl
O-(2,3,4,6-tetra-O-Acetyl-β-D-glucopyranosyl)-
stearate 4a (β) Yield 65.8%, Rf 0.56 (cyclohexane/
ethyl acetate, 3∶1, V∶V); [α]2D0 3.5 (c 1.0, MeOH);
1H NMR (CDCl3, 400 MHz) δ: 5.69 (d, J1-2=8.3 Hz,
1H, H-1), 5.23 (t, J=9.3 Hz, 1H, H-3), 5.13—5.06 (m,
1
acetate, 1∶1, V∶V); [α]2D0 11.0 (c 1.0, CH2Cl2); H
NMR (CDCl3, 400 MHz), δ: 5.36 (dd, J4-3=6.8 Hz,
J4-5=3.2 Hz, 1H, H-4Gal), 5.29 (d, J1-2=3.2 Hz, 1H,
H-1Glc), 5.27 (t, J=9.2 Hz, 1H, H-3Glc), 5.12 (dd,
J2-3=10.4 Hz, J2-1=7.6 Hz, 1H, H-2Gal), 4.97 (dd,
J2-3=9.3 Hz, J2-1=8.1 Hz, 1H, H-2Glc), 4.94 (dd,
J3-2=10.4 Hz, J3-4=3.3 Hz, 1H, H-3Gal), 4.51 (d,
'
2H, H-2, H-4), 4.27 (dd, J6-6 =12.5 Hz, J6-5=4.4 Hz,
'
'
1H, H-6), 4.07 (dd, J6-6 =12.4 Hz, J6 -5=2.1 Hz, 1H,
H-6'), 3.84—3.79 (m, 1H, H-5), 2.35—2.30 (m, 2H,
aliphatic OCCH2C17H35), 2.06, 2.00, 1.99, 1.98 (4×s,
12H, CH3CO), 1.22 (s, 30H, aliphatic OCCH2-
(CH2)15CH3), 0.85 (t, J = 6.3 Hz, 3H, aliphatic
OCC16H32CH3); 13C NMR (CDCl3, 100.6 MHz) δ:
171.35 (C=O, OCCH2C17H35), 170.14, 169.65, 168.96,
168.73 (C=O, Ac), 91.91 (C-1), 73.32 (C-3), 73.24
(C-5), 70.82 (C-2), 68.41 (C-4), 62.12 (C-6), 34.91
(aliphatic OCCH2C17H35), 32.83—29.87 (aliphatic
OCCH2(CH2)15CH3), 25.52, 23.68, 21.68, 21.56
(CH3CO, Ac), 15.18 (aliphatic OCC16H32CH3). HRMS
calcd for C32H54O11Na: (M+Na)+ 637.3621, found
637.3644.
'
J1-2=8.0 Hz, 1H, H-lGal), 4.46 (dd, J6-6 =12.2 Hz,
J6-5=2.1 Hz, 1H, H-6Glc), 4.18—4.04 (m, 3H, H-6'Glc,
H-6Gal, H-6'Gal), 3.88—3.86 (m, 2H, H-5Gal, H-4Glc),
3.79—3.71 (m, 1H, H-5Glc), 2.35 (t, J=7.5 Hz, 2H,
aliphatic OCCH2C17H35), 2.18, 2.16, 2.13, 2.11, 2.06,
2.05, 1.97 (7×s, 21H, CH3CO), 1.25 (s, 30H, aliphatic
OCCH2(CH2)15CH3), 0.88 (t, J=6.9 Hz, 3H, aliphatic
OCC16H32CH3); 13C NMR (CDCl3, 100.6 MHz) δ:
173.06 (C=O, OCCH2C17H35), 170.44, 170.33, 170.08,
169.58, 169.45, 169.14, 168.98 (C=O, Ac), 101.25
(C-1Gal), 100.97 (C-Glc), 75.50 (C-4Glc), 73.58
(C-5Glc), 72.99 (C-3Glc), 71.13 (C-3Gal), 71.06
(C-5Gal), 70.63 (C-2Glc), 69.09 (C-2Gal), 67.93
(C-4Gal), 62.20, 60.77 (C-6 Gal, C-6 Glc), 34.09 (aliph-
atic OCCH2C17H35), 31.90, 29.67—28.99 (aliphatic
OCCH2(CH2)15CH3), 20.93, 20.86, 20.82, 20.76, 20.71,
20.62, 20.49 (CH3CO, Ac), 14.09 (aliphatic OCC16H32-
CH3). HRMS calcd for C44H70O19Na (M + Na) +
925.4426, found 925.4501.
O-(2,3,4,6-tetra-O-Acetyl-β-D-galactopyranosyl)-
stearate 4b (α) Yield 5.2%; Rf 0.60 (cyclohexane/
ethyl acetate, 3∶1, V∶V); [α]2D0 62.0 (c 1.0, MeOH);
1H NMR (CDCl3, 400 MHz) δ: 6.38 (d, J1-2=1.8 Hz,
1H, H-1), 5.49 (d, J=1.0 Hz, 1H, H-3), 5.33—5.32 (m,
2H, H-2, H-4), 4.35—4.30 (m, 1H, H-5), 4.14—4.03 (m,
2H, H-6, H-6'), 2.40 (t, J=7.5 Hz, 2H, aliphatic
OCCH2C17H35), 2.16, 2.04, 2.02, 2.01 (4×s, 12H,
CH3CO), 1.26 (s, 30H, aliphatic OCCH2(CH2)15CH3),
0.88 (t, J=6.9 Hz, 3H, aliphatic OCC16H32CH3); 13C
NMR (CDCl3, 100.6 MHz) δ: 171.38 (C = O,
OCCH2C17H35), 169.95, 169.77, 169.73, 169.44 (C=O,
Ac), 89.87 (C-1), 69.35 (C-3), 69.07 (C-2, C-4), 67.15
(C-5), 61.96 (C-6), 35.11 (aliphatic OCCH2C17H35),
32.86, 30.64—29.99 (aliphatic OCCH2(CH2)15CH3),
25.91, 23.72, 21.68, 21.57 (CH3CO, Ac), 15.22
O-(2,3,4,6-tetra-O-Acetyl-β-D-galactopyranosyl)-
(1→4)-2,3,6-tri-O-acetyl-β-D-glucopyranosyl stearate
4c (β) Yield 57.3%; Rf 0.52 (cyclohexane/ethyl acetate,
1
1∶1, V∶V); [α]2D0 46.3 (c 1.0, CH2Cl2); H NMR
(CDCl3, 400 MHz) δ: 5.68 (d, J1-2=8.0 Hz, 1H, H-1
Glc), 5.35 (dd, J4-3=3.2 Hz, J4-5<1 Hz, 1H, H-4Gal),
5.25 (t, J=9.2 Hz, 1H, H-3Glc), 5.11 (dd, J2-3=10.4 Hz,
J2-1=8.0 Hz, 1H, H-2Gal), 5.05 (dd, J2-3=9.2 Hz,
J2-1=8.4 Hz, 1H, H-2Glc), 4.95 (dd, J3-2=10.4 Hz,
J3-4=3.2 Hz, 1H, H-3Gal), 4.57 (d, J1-2=8.0 Hz, 1H,
(aliphatic
OCC16H32CH3).
HRMS
calcd
for
C32H54O11Na (M+Na)+ 637.3621, found 637.3523.
'
O-(2,3,4,6-tetra-O-Acetyl-β-D-galactopyranosyl)-
stearate 4b (β) Yield 64.9%; Rf 0.52 (cyclohexane/
ethyl acetate, 3∶1, V∶V); [α]2D0 11.4 (c 1.0, MeOH);
1H NMR (CDCl3, 400 MHz) δ: 5.70 (d, J1-2=8.3 Hz,
1H, H-1), 5.49—5.38 (m, 1H, H-2), 5.32 (dd, J3-2=8.3
H-lGal), 4.47 (dd, J6-6 =12.2 Hz, J6-5=2.0 Hz, 1H,
H-6Glc), 4.16—4.05 (m, 3H, H-6'Glc, H-6Gal, H-6'Gal),
3.89—3.82 (m, 2H, H-5Gal, H-4Glc), 3.77—3.73 (m,
1H, H-5Glc), 2.34 (t, J = 7.5 Hz, 2H, aliphatic
OCCH2C17H35), 2.16, 2.12, 2.07, 2.05, 2.04, 2.01, 1.97
Chin. J. Chem. 2010, 28, 2245— 2248
© 2010 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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