32
Z. Ma et al. / Carbohydrate Research 339 (2004) 29–35
chromatography with 2:1 petroleum ether–EtOAc as the
eluent to give 7 (462 mg, 80.4%) as a foamy solid: ½aꢀ
5.71 (dd, 1H, J2;3 9.0 Hz, J3;4 10.9 Hz, Glcp H-3), 5.64
(dd, 1H, J1;2 1.9 Hz, J2;3 3.2 Hz, Manp H-2), 5.48 (dd,
1H, J2;3 3.4 Hz, J3;4 10.5 Hz, Manp H-3), 5.41 (d, 1H, J1;2
1.5 Hz, Manp H-1), 5.37 (dd, 1H, J1;2 1.7 Hz, J2;3 3.4 Hz,
Manp H-2), 5.17 (d, 1H, J1;2 1.7 Hz, Manp H-1), 4.93 (d,
1H, J1;2 1.9 Hz, Manp H-1), 4.81 (d, 1H, J1;2 3.4 Hz, Glcp
H-1), 3.47 (s, 3H, CH3O), 2.02 (s, 3H, CH3CO), 1.83 (s,
3H, CH3CONH); 13C NMR(100 MHz, CDCl 3): d
170.2, 169.2 (CH3CO, CH3CONH), 166.8, 166.6, 166.5,
166.2, 166.1, 165.6, 165.5, 165.3, 165.1, 164.5 (PhCO),
133.4–132.9, 130.0–128.2 (PhCO), 99.8, 99.6, 98.7, 98.3
(C-1), 76.1, 73.9, 73.4, 72.7, 70.8, 70.4, 69.8, 69.6, 69.5,
68.7, 68.3, 68.0, 67.1, 66.2, 66.0, 63.9, 63.5, 63.1, 54.4,
52.1 (C-2–C-6), 55.4 (CH3O), 23.1, 20.6 (CH3CONH,
CH3CO). Anal. Calcd for C99H89NO32: C, 65.88; H, 4.97.
Found: C, 65.71; H, 5.03.
D
1
)12.0 (c 1.0, CHCl3); H NMR(400 MHz, CDCl ): d
3
8.14–7.19 (m, 20H, 4Ph), 5.88 (d, 1H, JH–C–N–H 9.5 Hz,
NHAc), 5.72 (dd, 1H, J2;3 8.8 Hz, J3;4 10.0 Hz, H-3),
5.58–5.53 (m, 2H, H-30, H-40), 5.38 (d, 1H, J1;2 1.9 Hz,
H-10), 5.34 (dd, 1H, J1;2 1.9 Hz, J2;3 2.5 Hz, H-20), 4.80 (d,
1H, J1;2 3.4 Hz, H-1), 4.73 (dd, 1H, J5;6a 2.0 Hz, J6a;6b
12.2 Hz, H-6a), 4.64 (dd, 1H, J5;6b 4.0 Hz, J6a;6b 12.2 Hz,
H-6b), 4.47 (m, 1H, H-2), 4.32 (dd, 1H, J5;6b 4.1 Hz, J6a;6b
12.4 Hz, H-60b), 4.26 (dd, 1H, J3;4 ¼ J4;5 ¼ 10:0 Hz,
H-4), 4.21–4.17 (m, 2H, H-5, H-50), 3.97 (dd, 1H, J5;6a
2.1 Hz, J6a;6b 12.4 Hz, H-60a), 3.48 (s, 3H, CH3O), 2.06 (s,
3H, CH3CO), 1.91 (s, 3H, CH3CO), 1.83 (s, 3H,
CH3CONH). Anal. Calcd for C47H47NO17: C, 62.87; H,
5.28. Found: C, 62.59; H, 5.15.
3.5. Methyl 2,3-di-O-benzoyl-a-
D
-mannopyranosyl-
-
3.7. Methyl 2-O-acetyl-3,4,6-tri-O-benzoyl-a-
pyranosyl-(1 ! 2)-3,4,6-tri-O-benzoyl-a- -mannopyrano-
-mannopyranosyl-
D-manno-
(1 ! 4)-2-acetamido-3,6-di-O-benzoyl-2-deoxy-a-
D
D
glucopyranoside (8)
syl-(1 ! 6)-2,3,4-tri-O-benzoyl-a-
D
(1 ! 4)-2-acetamido-3,6-di-O-benzoyl-2-deoxy-a-
D-
To a solution of 7 (433 mg, 0.48 mmol) in anhyd CH2Cl2
(10 mL) was added anhyd MeOH (50 mL), and then
acetyl chloride (1.5 mL) was added to the reaction
mixture at 0 °C. The solution was stoppered in a flask
and stirred at rt until TLC (1:1 petroleum ether–EtOAc)
showed that the starting material disappeared. The so-
lution was neutralized with Et3N, then concentrated to
dryness. The residue was passed through a short silica
gel column to give 8 (305 mg, 77.7%) as a foamy solid:
glucopyranoside (11)
To a solution of 10 (241 mg, 0.13 mmol) in pyridine
(2 mL) was added benzoyl chloride (23.4 lL, 0.20 mmol).
After stirring the mixture overnight at rt, TLC (2:3 pe-
troleum ether–EtOAc) indicated that the reaction was
complete. Methanol (2 drops) was added to the reaction
mixture, and stirring was continued for 10 min. Water
(10 mL) was added, the mixture was extracted with
CH2Cl2 (3 · 10 mL), and the extracts were washed with
1 M HCl and satd aq NaHCO3, dried (Na2SO4), and
concentrated. Purification by flash chromatography (1:1
petroleum ether–EtOAc) gave 11 as a foamy solid
½aꢀ +5.0 (c 1.0, CHCl3); 1H NMR(400 MHz, CDCl 3): d
D
8.12–7.18 (m, 20H, 4Ph), 5.94 (d, 1H, JH–C–N–H 9.6 Hz,
NHAc), 5.68 (dd, 1H, J2;3 8.9 Hz, J3;4 10.9 Hz, H-3), 5.44
(dd, 1H, J2;3 2.5 Hz, J3;4 9.8 Hz, H-30), 5.29–5.27 (m, 2H,
H-10, H-20), 4.80 (d, 1H, J1;2 3.5 Hz, H-1), 4.72 (dd, 1H,
J5;6a 1.9 Hz, J6a;6b 12.3 Hz, H-6a), 4.65 (dd, 1H, J5;6b
3.7 Hz, J6a;6b 12.3 Hz, H-6b), 4.41–4.51 (m, 1H, H-2),
4.25–4.11 (m, 3H, H-4, H-5), 3.92–3.75 (m, 4H, H-40,
H-50, H-60a, H60b), 3.48 (s, 3H, CH3O), 1.83 (s, 3H,
CH3CONH). Anal. Calcd for C43H43NO15: C, 63.46; H,
5.33. Found: C, 63.68; H, 5.44.
(245 mg, 96.2%): ½aꢀ )3.5 (c 1.0, CHCl3); 1H NMR
D
(400 MHz, CDCl3): d 8.03–7.12 (m, 55H, 11Ph), 6.03
(dd, 1H, J3;4 ¼ J4;5 ¼ 10:1 Hz, H-4), 5.99–5.76 (m, 7H,
NHAc, Manp 4 H-3, 2 H-4), 5.58 (dd, 1H, J1;2 1.9 Hz,
J
2;3 3.0 Hz, Manp H-2), 5.45–5.43 (m, 2H, Manp H-1, H-
2), 5.06 (d, 1H, J1;2 1.6 Hz, Manp H-1), 4.91 (d, 1H, J1;2
1.5 Hz, Manp H-1), 4.83 (d, 1H, J1;2 3.4 Hz, Glcp H-1),
3.52 (s, 3H, CH3O), 2.01 (s, 3H, CH3CO), 1.86 (s, 3H,
CH3CONH). Anal. Calcd for C106H93NO33: C, 66.70; H,
4.91. Found: C, 66.58; H, 4.80.
3.6. Methyl 2-O-acetyl-3,4,6-tri-O-benzoyl-a-
pyranosyl-(1 ! 2)-3,4,6-tri-O-benzoyl-a- -mannopyrano-
-mannopyranosyl-
D-manno-
D
syl-(1 ! 6)-2,3-di-O-benzoyl-a-
D
(1 ! 4)-2-acetamido-3,6-di-O-benzoyl-2-deoxy-a-
D
-
3.8. Methyl 3,4,6-tri-O-benzoyl-a-D-mannopyranosyl-
glucopyranoside (10)
(1 ! 2)-3,4,6-tri-O-benzoyl-a-
D
-mannopyranosyl-
-mannopyranosyl-
(1 ! 6)-2,3,4-tri-O-benzoyl-a-
D
Donor 9 (213 mg, 0.18 mmol) was coupled with acceptor
8 (125 mg, 0.15 mmol) as described in the general pro-
cedure, and the product was purified by chromatogra-
phy with 1:1 petroleum ether–EtOAc as the eluent to
(1 ! 4)-2-acetamido-3,6-di-O-benzoyl-2-deoxy-a-
D-
glucopyranoside (12)
Compound 11 (228 mg, 0.12 mmol) were deacetylated
under the same conditions as that used for preparation
of 8 from 7, giving 12 (166 mg, 74.5%) as a foamy solid:
½aꢀ )12.5 (c 1.0, CHCl3); 1H NMR(400 MHz, CDCl ):
give 10 (251 mg, 90.5%) as a foamy solid: ½aꢀ )8.6 (c
D
1
1.0, CHCl3); H NMR(400 MHz, CDCl ): d 8.06–7.18
3
(m, 50H, 10Ph), 5.95–5.90 (m, 4H, NHAc, Manp H-3, 2
H-4), 5.86 (dd, 1H, J2;3 3.2 Hz, J3;4 10.0 Hz, Manp H-3),
3
D
d 8.02–7.14 (m, 55H, 11Ph), 6.05–5.72 (m, 8H, NHAc,