I. Ohtsuka et al. / Carbohydrate Research 337 (2002) 2037–2047
2043
PhCH), 4.95, 4.93, 4.81, 4.76, 4.70, 4.45 (each d, 6 H,
Jgem 10.9 Hz, 3 PhCH2), 4.37 (d, 1 H, J1,2 7.3 Hz, H-1),
4.22 (t, 1 H, J4,5 4.9 Hz, H-4%), 4.19 (s, 1 H, H-1%), 4.10
(dd, 1 H, H-6a), 3.99 (t, 1 H, J5,6b 9.2 Hz, H-6b), 3.93
(q, 1 H, OCH2CH2Si), 3.82 (dd, 1 H, J5,6b 9.2 Hz, J6a,6b
3.1 Hz, H-6a%), 3.78–3.76 (m, 2 H, H-2%, H-3%), 3.63 (t,
1 H, J3,4 8.5 Hz, H-3), 3.56 (q, 1 H, OCH2CH2Si),
3.51–3.48 (m, 2 H, H-5, H-6b%), 3.40–3.35 (m, 2 H,
H-2, H-4), 3.10 (t, 1 H, H-5%), 1.62 (s, 1 H, OH), 1.01
(s, 9 H, 3 CH3), 0.98 (t, 2 H, OCH2CH2Si), −0.08 (s,
J3,4 9.2 Hz, H-3), 3.44–3.36 (m, 2 H, H-5, H-5%), 3.27
(t, 1 H, J2,3 9.2 Hz, H-2), 0.92 (t, 2 H, OCH2CH2Si),
−0.08 (s, 9 H, Si(CH3)3). MALDI-TOFMS: Calcd for
C52H60O12Si: m/z 904. Found: m/z 927 [M+Na]+.
2-(Trimethylsilyl)ethyl 3,4,6,-tri-O-acetyl-2-deoxy-2-
phthalimido - i -
4,6-O-benzylidene-i-
tri-O-benzyl-i- -glucopyranoside (14).—A solution of
12 (140 mg, 0.15 mmol), 3,4,6-tri-O-acetyl-2-phthal-
imido-b- -glucopyranosyl bromide (13: 169 mg, 0.31
D
- glucopyranosyl - (13)-2-O-benzoyl-
D
-mannopyranosyl-(14)-2,3,6-
D
D
,
9
H, Si(CH3)3). MALDI-TOFMS: Calcd for
mmol) and 4 A MS in dry CH2Cl2 (2.0 mL) was stirred
for 2 h at rt, then cooled to −25 °C. Silver triflate
(AgOTf: 159 mg, 0.20 mmol) was added to the mixture,
which was stirred for 1 h at −25 °C and for 24 h at rt.
The insoluble materials were filtered off, and the filtrate
was washed with water, dried (Na2SO4), and concen-
trated. The product was purified by silica gel column
chromatography using 1:1 hexane–AcOEt as eluent to
C61H74O11Si2: m/z 1038. Found: m/z 1061 [M+Na]+.
HR FABMS: Calcd for C61H75O11Si2 [M+H]+:
1039.4847, Found 1039.4828.
2-(Trimethylsilyl)ethyl
dene-3-O-tert-butyldiphenylsilyl-i-
4)-2,3,6-tri-O-benzyl-i- -glucopyranoside (11).—To
2-O-benzoyl-4,6-O-benzyli-
D-mannopyranosyl-(1
D
a solution of 10 (550 mg, 0.53 mmol) in pyridine (10
mL) were added benzoyl chloride (5.0 mL). The reac-
tion mixture was stirred for 5 h at rt, then extracted
with CHCl3, washed with 5% HCl, dried (Na2SO4), and
concentrated. The product was purified by silica gel
column chromatography using 10:1 hexane–AcOEt as
eluent to give 11 (540 mg, 89%). [h]D −9.3° (c 3.0,
1
give 14 (147 mg, 72%). [h]D −15.3° (c 0.2, CHCl3); H
NMR (CDCl3): l 8.08–7.14 (m, 29 H, 6 Ph), 5.64 (t, 1
H, J2%%,3%%=3%%,4%% 9.8 Hz, H-3%%), 5.59 (s, 1 H, PhCH), 5.57
(d, 1 H, J1,2 8.6 Hz, H-1%%), 5.46 (d, 1 H, J2%,3% 3.0 Hz,
H-2%), 4.86, 4.84, 4.73, 4.68, 4.62, 4.42 (each d, 6 H,
Jgem 11.2 Hz, 3 PhCH2), 4.53 (s, 1 H, H-1%), 4.35 (dd, 1
H, J5,6a 10.4 Hz, J6a,6b 4.9 Hz, H-6a%), 4.23 (d, 1 H, J1,2
7.9 Hz, H-1), 4.30–3.89 (m, 9 H, H-3%, H-4%, H-6a,
H-6b, H-6b% H-2%%, H-6a%%, H-6b%%, OCH2CH2Si,), 3.83
(q, 1 H, OCH2CH2Si), 3.77 (q, 1H, H-5), 3.57 (t, 1 H,
J3,4 9.2 Hz, H-3), 3.45–3.25 (m, 3 H, H-4, H-5%, H-5%%),
3.22 (t, 1 H, J2,3 8.5 Hz, H-2), 2.10, 2.08, 2.06 (each S,
9H, 3 Ac), 0.95 (t, 2 H, OCH2CH2Si), −0.08 (s, 9 H,
Si(CH3)3), 4.23 (d, 1 H, J1,2 7.9 Hz, H-1). MALDI-
TOFMS: Calcd for C72H79NO21Si: m/z 1321. Found:
m/z 1344 [M+Na]+. HR FABMS: Calcd for
C72H80NO21Si [M+H]+:1322.4991, Found 1322.4978.
2-(Trimethylsilyl)ethyl 2-acetamido-3,4,6,-tri-O-acet-
1
CHCl3); H NMR (CDCl3): l 8.17–6.97 (m, 35 H, 7
Ph), 5.55 (d, 1 H, H-2%), 5.18 (s, 1 H, PhCH), 4.90,
4.86, 4.76, 4.71, 4.64, 4.37 (each d, 6 H, Jgem 11.0 Hz, 3
PhCH2), 4.47 (s, 1 H, H-1%), 4.27 (d, 1 H, J1,2 7.9 Hz,
H-1), 4.22 (dd, 1 H, J5,6a 10.4 Hz, J6a,6b 4.9 Hz, H-6a%),
4.03 (dd, 1 H, J2,3 3.7 Hz, J3,4 9.8 Hz, H-3%), 3.98 (dd,
1 H, H-6a), 3.97 (t, 1 H, J4,5 9.2 Hz, H-4%), 3.94 (q, 1 H,
OCH2CH2Si), 3.79 (t, 1 H, J5,6b 10.4 Hz, H-6b%), 3.59–
3.50 (m, 3 H, H-3, H-6b, OCH2CH2Si), 3.35 (q, 1 H,
H-5), 3.32 (t, 1 H, J4,5 9.8 Hz, H-4), 3.26 (d, 1 H, H-2),
3.20 (q, 1 H, H-5%), 0.92 (t, 2 H, OCH2CH2Si), 0.82 (s,
9 H, 3 CH3), −0.08 (s, 9 H, Si(CH3)3). MALDI-
TOFMS: Calcd for C68H78O12Si2: m/z 1142. Found:
m/z 1165 [M+Na]+.
yl-2-deoxy - i -
acetyl-i- -mannopyranosyl-(14)-2,3,6-tri-O-acetyl-
i- -glucopyranoside (15).—A solution of 14 (147 mg,
D
- glucopyranosyl - (13) - 2,4,6 - tri-O-
D
2-(Trimethylsilyl)ethyl
dene-i- -mannopyranosyl-(14)-2,3,6-tri-O-benzyl-
i- -glucopyranoside (12).—To a solution of 11 (270
2-O-benzoyl-4,6-O-benzyli-
D
D
0.11 mmol) in MeOH (3.0 mL) and AcOH (10 mL) was
hydrogenolyzed in the presence of 10% Pd–C (140 mg)
for 24 h at rt, then filtered and concentrated. The
residue was dissolved in EtOH (5.0 mL), and hydrazine
monohydrate (5.0 mL) was added. The reaction mix-
ture was refluxed for 3 h, then concentrated. The
residue was acetylated with Ac2O (3.0 mL) in pyridine
(4.0 mL). The mixture was poured into ice-water and
extracted with CHCl3. The extract was washed sequen-
tially with 5% HCl, aq NaHCO3 and water, dried
(Na2SO4), and concentrated. The product was purified
by silica gel column chromatography using 2:1 hexane–
AcOEt as eluent to give 15 (93.0 mg, 83%). [h]D
D
mg, 0.24 mmol) in THF (3.0 mL) were added t-Bu4NF
(TBAF, 1.0 M solution in THF 650 mL). The reaction
mixture was stirred for 1 h at rt, then extracted with
CHCl3, washed with 5% HCl, dried (Na2SO4), and
concentrated. The product was purified by silica gel
column chromatography using 1:1 hexane–AcOEt as
eluent to give 12 (140 mg, 80%). [h]D −20.5° (c 0.5,
1
CHCl3); H NMR (CDCl3): l 8.07–7.16 (m, 25 H, 5
Ph), 5.67 (d, 1 H, H-2%), 5.57 (s, 1 H, PhCH), 4.89,
4.85, 4.79, 4.74, 4.70, 4.65 (each d, 6 H, Jgem 11.0 Hz, 3
PhCH2), 4.76 (s, 1 H, H-1%), 4.35 (dd, 1 H, J5,6a 10.4
Hz, J6a,6b 4.9 Hz, H-6a%), 4.33 (d, 1 H, J1,2 7.9 Hz, H-1),
4.23 (t, 1 H, H-6a), 4.09 (dd, 1 H, J5,6a 9.7 Hz, J6a,6b 4.8
Hz, H-6b), 4.01–3.85 (m, 5 H, H-3%, OCH2CH2Si, H-4,
H-4%, H-6b%), 3.61 (q, 1 H, OCH2CH2Si), 3.57 (t, 1 H,
1
−88.1° (c 0.5, CHCl3); H NMR (CDCl3): l 5.63 (d, 1
H, NH) 5.39 (brs. 1 H, H-2%), 5.18–5.12 (m, 2 H, H-3,
H-3%%), 5.06 (t, 1 H, H-4%), 4.89–4.84 (m, 2 H, H-2,
H-4%%), 4.69 (d, 1 H, J1,2 8.5 Hz, H-1%%), 4.51 (s, 1 H,