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G. Gu et al. / Carbohydrate Research 339 (2004) 1155–1162
2.06 (s, 3H, CH3CO), 4.13 (dd, 1H, J6a;6b 12.4, J5;6a
4.8 Hz, H-6a), 4.20 (dd, 1H, J6a;6b 12.4, J5;6b 4.0 Hz, H-
6b0), 4.38 (ddd, 1H, H-50), 4.45–4.53 (m, 2H, H-5, H-6a),
4.66–4.74 (m, 2H, H-3, H-6b), 5.33 (dd, 1H, J1;2 1.7, J2;3
3.1 Hz, H-20), 5.36 (d, 1H, H-10), 5.67 (dd, 1H, J2;3 3.2,
J3;4 10.0 Hz, H-30), 5.81–5.87 (m, 2H, H-2, H-4), 6.14 (t,
1H, J3;4 ¼ J4;5 ¼ 9:8 Hz, H-40), 6.60 (d, 1H, J1;2 1.9 Hz,
H-1), 7.20–8.13 (m, 30H, Ph), 8.86 (s, 1H, NH). Anal.
Calcd for C58H48Cl3NO18: C, 60.40; H, 4.19. Found: C,
60.79; H, 4.23.
3.15. Octyl 6-O-acetyl-2,3,4-tri-O-benzoyl-a-
pyranosyl-(1 ! 3)-2,4,6-tri-O-benzoyl-a- -mannopyrano-
-mannopyranosyl-
D-manno-
D
syl-(1 ! 3)-2,4,6-tri-O-benzoyl-a-
D
(1 ! 3)-2,4,6-tri-O-benzoyl-a-
D
D
-mannopyranosyl-
-mannopyranoside (18)
(1 ! 2)-3,4,6-tri-O-benzoyl-a-
Compound 17 (682 mg, 0.42 mmol) and 13 (432 g,
0.40 mmol) were pre-dried in one flask under vacuum at
60 °C for 3 h. The mixture was then dissolved in CH2Cl2
(5 mL). To the solution at 0 °C was slowly added
Me3SiOTf (8 lL, 0.04 mmol) under an N2 atmosphere.
The reaction mixture was stirred for 2 h under these
conditions, neutralized with Et3N and concentrated
under reduced pressure, then purified by column chro-
3.13. Allyl 6-O-acetyl-2,3,4-tri-O-benzoyl-a-
-mannopyrano-
-mannopyranoside
D-manno-
pyranosyl-(1 ! 3)-2,4,6-tri-O-benzoyl-a-
D
syl-(1 ! 3)-2,4,6-tri-O-benzoyl-a-
D
matography using 2:1 petroleum ether–EtOAc as the
25
D
(16)
eluent gave 18 (732 mg, 72%) as a syrup: ½a )104 (c 4,
1
CHCl3); H NMR(CDCl ): d 0.87 (t, 3H, CH2CH3),
3
Syrupy compound 16 (1.03 g, 85%) was prepared from 8
(422 mg, 0.79 mmol) and 15 (960 mg, 0.83 mmol) in a
1.22–1.31 (m, 10H, CH2(CH2)5CH3), 1.52–1.58 (m, 2H,
–OCH2CH2), 3.31 (dt, 1H, J 9.9, 6.5 Hz, –OCH2), 3.56–
3.67 (m, 2H, H-6aV, –OCH2), 3.79 (dd, 1H, J6a;6b 12.2,
J5;6b 3.9 Hz, H-6bV), 3.80–4.05 (m, 4H, 3 · H-6, H-5),
4.25–4.37 (m, 6H, H-2I, H-3II, 3 · H-5, H-6), 4.39–4.54
(m, 4H, H-3III, H-5, 2 · H-6), 4.57–4.70 (m, 3H, H-3IV,
2 · H-6), 4.90 (d, 1H, J1;2 1.7 Hz, H-1I), 4.99 (d, 1H, J1;2
1.8 Hz, H-1III), 5.09 (d, 1H, J1;2 1.7 Hz, H-1IV), 5.12 (dd,
1H, J2;3 3.2 Hz, H-2III), 5.15 (dd, 1H, J2;3 4.6 Hz, H-2IV),
5.25 (d, 1H, J1;2 1.5 Hz, H-1II), 5.32 (dd, 1H, J2;3 4.9 Hz,
H-2II), 5.36 (d, 1H, J1;2 1.6 Hz, H-1V), 5.51 (dd, 1H, J2;3
3.1, J3;4 10.0 Hz, H-3V), 5.63 (t, 1H, J3;4 ¼ J4;5 ¼ 10:0 Hz,
H-4V), 5.80–5.98 (m, 6H, H-2V, H-3I, 4 · H-4), 7.23–8.06
(m, 75H, Ph); 13C NMR: d 14.05, 22.61, 26.03, 29.19,
29.28, 29.35, 31.75 (7C, –OCH2 (CH2)6CH3), 20.41 (1C,
CH3CO), 62.03, 62.08, 62.30, 63.05, 63.74, 66.32, 67.01,
67.30, 67.62, 68.11, 68.48, 68.73, 69.02, 69.22, 69.32,
69.72, 69.90, 70.97, 71.18, 71.29, 71.52, 75.91, 76.18,
76.40, 77.20, 77.56 (26 C), 98.54, 98.66, 99.17, 99.18,
99.57 (5C-1), 164.42, 164.53, 164.91, 165.06, 165.14,
165.28, 165.34, 165.62, 165.70, 165.77, 165.83, 166.08,
166.14 (15C, PhCO), 170.27 (1C, CH3CO). Anal. Calcd
for C145H130O42: C, 68.44; H, 5.15. Found: C, 68.56; H,
5.20.
25
similar fashion to that of making 12: ½a )97 (c 2,
D
CHCl3); 1H NMR(CDCl 3): d 1.91 (s, 3H, CH3CO), 3.66
(dd, 1H, J6a;6b 12.3, J5;6a 2.7 Hz, H-6aIII), 3.87 (dd, 1H,
J5;6b 4.2 Hz, H-6bIII), 4.03 (ddd, 1H, J4;5 9.8 Hz, H-5III),
4.06–4.23 (m, 2H, CH2@CHCH2O–), 4.26–4.41 (m, 4H,
H-3I, H-3II, H-5I, H-5II), 4.46 (dd, 1H, J6a;6b 12.2, J5;6
4.8 Hz, H-6), 4.58–4.69 (m, 3H, 3 · H-6), 4.94 (d, 1H, J1;2
1.7 Hz, H-1II), 5.10 (d, 1H, J1;2 1.6 Hz, H-1I), 5.19 (dd,
1H, J2;3 3.0 Hz, H-2II), 5.21–5.33 (m, 3H, H-2III,
CH2@CHCH2O–), 5.36 (d, 1H, J1;2 1.7 Hz, H-1III), 5.54
(dd, 1H, J2;3 3.2, J3;4 10.1 Hz, H-3III), 5.65–5.71 (m, 2H,
H-2I, H-4III), 5.85–5.99 (m, 3H, 2 · H-4, CH2@
CHCH2O–), 7.21–8.19 (m, 45H, Ph). Anal. Calcd
for C86H74O26: C, 67.80; H, 4.90. Found: C, 67.99; H,
4.92.
3.14. 6-O-Acetyl-2,3,4-tri-O-benzoyl-a-
-mannopyranosyl-
-mannopyranosyl tri-
D-mannopyrano-
syl-(1 ! 3)-2,4,6-tri-O-benzoyl-a-
D
(1 ! 3)-2,4,6-tri-O-benzoyl-a-
D
chloroacetimidate (17)
Compound 16 (980 mg, 0.64 mmol) was treated as
described for 6 to afford syrupy 17 (702 mg, 67% for two
3.16. Octyl 2,3,4-tri-O-benzoyl-a-
(1 ! 3)-2,4,6-tri-O-benzoyl-a- -mannopyranosyl-(1 ! 3)-
2,4,6-tri-O-benzoyl-a-
-mannopyranosyl-(1 ! 3)-2,4,6-
tri-O-benzoyl-a-
-mannopyranosyl-(1 ! 2)-3,4,6-tri-O-
benzoyl-a- -mannopyranoside (19)
D-mannopyranosyl-
25
D
steps): ½a )99 (c 1, CHCl3); 1H NMR(CDCl ): d 1.90
D
3
(s, 3H, CH3CO), 3.70 (dd, 1H, J6a;6b 12.2, J5;6a 2.5 Hz, H-
6aIII), 3.90 (dd, 1H, J5;6b 4.3 Hz, H-6bIII), 4.01–4.06 (m,
1H, H-5III), 4.30–4.52 (m, 5H, H-6, 2 · H-3, H-5I, H-5II),
4.57 (dd, 1H, J 12.5, J5;6 2.3 Hz, H-6), 4.67–4.72 (m, 2H,
2 · H-6), 4.98 (d, 1H, J1;2 1.7 Hz, H-1II), 5.21 (dd, 1H,
J2;3 3.0 Hz, H-2II), 5.28 (dd, 1H, J2;3 2.7 Hz, H-2III), 5.40
(d, 1H, J1;2 1.4 Hz, H-1III), 5.55 (dd, 1H, J2;3 3.1, J3;4
10.0 Hz, H-3III), 5.69 (t, 1H,J3;4 ¼ J4;5 ¼ 10:0 Hz, H-4III),
5.87 (dd, 1H, J2;3 3.0 Hz, H-2I), 6.00–6.10 (m, 2H, 2 · H-
4), 6.56 (d, 1H, J1;2 1.7 Hz, H-1I), 7.22–8.09 (m, 45H,
Ph), 8.84 (s, 1H, NH). Anal. Calcd for C85H70Cl3NO26:
C, 62.72; H, 4.33. Found: C, 62.97; H, 4.25.
D
D
D
To a solution of compound 18 (526 mg, 0.21 mmol) in 2:1
CH2Cl2–MeOH (9 mL) was added acetyl chloride
(0.4 mL) dropwise in 10 min. The reaction mixture was
stirred overnight until the reaction was complete. The
mixture was neutralized with pyridine (0.5 mL),
co-evaporated with toluene to dryness under diminished
pressure, and purified on a silica gel column with 2:1
petroleum ether–EtOAc as the eluent to give syrupy 19