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stirred for 30 min and propargyl bromide (80% in toluene,
Synthesis of 2 -Chloroethyl a-L-Fucoside 4
8
00 lL, 6.9 mol) was added via a syringe. The mixture was
In a two-necked 100-mL round-bottom flask, a mixture of a-
and b-L-fucose (1.64 g, 10.00 mmol), 2-chloroethanol
kept at ambient temperature for a further 2 h and then
stirred at 70 C for 6 h. DCM (50 mL) was added and the
solution was washed with HCl (1 N aqueous solution)
followed by distilled water (33). The solvent was removed
under reduced pressure to give the alkyne end-capped PE-b-
PEG 1 (4.6 g, 88%).
ꢁ
1
(10 mL), and Dowex 50W-100 (H ) (1.00 g) was stirred
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under N2 atmosphere at 80 C for 2 h. The mixture was
cooled to room temperature. The resin was removed by
filtration and washed with ethanol (33 2 mL). The solvent
was removed from the filtrate under reduced pressure. The
crude product was recrystallized with ethanol to give the
1
H-NMR (400 MHz, CDCl ) d 4.14 (s, 2H, AOACH ACBCH),
0
3
2
2 -chloroethyl a-L-fucoside 4 as crystals (1.2 g, 55%).
3.58 (m, 12H, ACH ACH AOA), 3.37 (t, J 5 7.08 Hz, 2H),
2 2
1
2.81 (s, 1H), 2.36 (s, 1H, ACH ACBCH), 1.20 (bs, 49H,
H-NMR (400 MHz, D O): d 4.84 (d, J 5 3.9 Hz, 1H), 4.07
2
2
CH ACH ACH A), (t, J 5 6.59 Hz, 3H, CH ACH A).
(q, J 5 7.1, 6.4 Hz, 1H), 3.88–3.61 (m, 7H), 1.11 (d, J 5 6.6
3
2
2
3
2
1
3
Hz, 3H). C-NMR (101 MHz, D O): d 98.60, 71.81, 69.54,
2
Synthesis of 2-Azidoethanol 2
68.47, 67.99, 66.89, 43.41, 15.25.
In a round-bottom flask, sodium azide (7 g, 108 mmol) was
dissolved in water (20 mL). 2-Chloroethanol (5.6 mL, 83
mmol) was added and the mixture was then stirred at 80 C
0
Synthesis of 2 -Chloroethyl 2,3,4-Tri-O-acetyl-
a-L-fucoside 5
ꢁ
for 24 h. The reaction mixture was cooled down to room
temperature, saturated with sodium chloride, and the prod-
uct was extracted with DCM (33 20 mL). The organic layer
was dried over sodium sulfate and then the solvent was
removed under reduced pressure to obtain 2-azidoethanol 2
as a colorless liquid (7.5 g, 80%).
In a one-necked round-bottom flask, 2-chloroethyl a-L-fuco-
side 4 (400 mg, 1.76 mmol) was dissolved in a mixture of
pyridine/acetic anhydride (1:1, v/v, 5 mL) at ambient tem-
perature for 2 h. The reaction was quenched by stirring with
ice (6 g) for 1 h. The product was extracted with DCM
(60 mL) and washed with 1 M HCl (33 40 mL) and brine
(
33 40 mL). The organic layer was dried over sodium sul-
1
3
H-NMR (400 MHz, CDCl ) d 3.71 (q, J 5 5.7 Hz, 2H,
fate and then the solvent was removed under reduced pres-
sure. The crude product was purified by flash column
chromatography on silica gel using dichloromethane/EtOAc
ACH AOH), 3.37 (t, J 5 5.0 Hz, 2H, ACH AN ), 2.60
2
2
3
1
3
(
t, J 5 5.8 Hz, 1H, ACH AOH). C-NMR (101 MHz, CDCl3):
2
d 61.40 (ACH AOH), 53.49 (ACH AN ).
0
2
2
3
(
9:1, v/v) as an eluent to give the 2 -chloroethyl 2,3,4-tri-O-
acetyl-a-L-fucoside 5, R 5 0.55 (373 mg, 60%).
f
0
Synthesis of 2 -Azidoethyl 2,3,4,6-Tetra-O-acetyl-b-D-
glucoside 3
1
H-NMR (400 MHz, CDCl ): d 5.31 (dd, J 5 10.5, 3.4 Hz, 1H),
3
In a two-necked 100-mL round-bottom flask, b-D-glucose
penta-acetate (5.0 g, 12.8 mmol) was dissolved in dry DCM
5
(
.24 (dd, J 5 3.4, 1.3 Hz, 1H), 5.09–5.00 (m, 2H), 4.18
q, J 5 7.0, 6.5 Hz, 1H), 3.86 (dt, J 5 11.0, 5.4 Hz, 1H), 3.68
(ddd, J 5 11.1, 6.0, 5.0 Hz, 1H), 3.59 (t, J 5 5.6 Hz, 2H), 2.10
s, 3H), 2.02 (s, 3H), 1.93 (s, 3H), 1.08 (d, J 5 6.6 Hz, 3H).
C-NMR (101 MHz, CDCl ): d 170.55, 170.54, 169.99, 96.47,
3
1.09, 68.60, 68.12, 67.91, 64.74, 42.71, 20.80, 20.68, 20.63,
(
25 mL) under N atmosphere. 2-Azidoethanol 2 (1.9 g, 22.3
2
mmol) was added to this solution by a syringe. The resulting
(
ꢁ
13
solution was stirred under N and cooled to 0 C. BF ꢂEt O
2
3
2
ꢁ
(
2.1 mL, 16.7 mmol) was then added dropwise at 0 C. The
mixture was stirred for 1 h at 0 C and then overnight at
ambient temperature. The mixture was diluted with DCM
7
1
ꢁ
5.85. HR ESI MS: m/z 337.20 corresponds to
3
7
1
35
1
[M( Cl) 1 Na] , m/z 375.00 corresponds to [M( Cl) 1 Na]
1
(
50 mL) and washed with cold water and with saturated
and m/z 273.20 corresponds to [M-(OCH CH Cl)] .
2
2
aqueous NaHCO , dried over anhydrous sodium sulfate, and
3
0
concentrated in rotary evaporator to obtain a viscous liquid
crude residue. The product was purified by recrystallization
Synthesis of 2 -Azidoethyl 2,3,4-Tri-O-acetyl-
a-L-fucoside 6
0
from the solution of methanol in order to obtain the 2 -azi-
In a two-necked 100-mL round-bottom flask, a suspension of
2 -chloroethyl 2,3,4-tri-O-acetyl-a-L-fucoside 5 (440 mg, 1.25
0
doethyl-2,3,4,6-tetra-O-acetyl-b-D-glucoside 3 (2.5 g, 45%).
mmol), NaI (188 mg, 1.25 mmol), and sodium azide (813
mg, 12.5 mmol) in DMF (6 mL) was stirred at 80 C for 18
h. The solvent was evaporated under reduced pressure. DCM
1
H-NMR (400 MHz, CDCl ): d 5.15 (t, J 5 9.47 Hz, 1H), 5.03
ꢁ
3
(dd, J 5 10.0, 9.3 Hz, 1H), 4.95 (dd, J 5 9.6, 7.9 Hz, 1H), 4.53
(d, J 5 7.9 Hz, 1H), 4.19 (dd, J 5 12.3, 4.7 Hz, 1H), 4.10
(dd, J 5 12.3, 2.5 Hz, 1H), 3.96 (ddd, J 5 10.7, 4.9, 3.5 Hz,
(
150 mL) was added and washed with water (30 mL) and
with brine (33 30 mL). The organic layer was dried over
1
H), 3.71–3.56 (m, 2H), 3.47–3.38 (m, 1H), 3.22 (ddd,
sodium sulfate and the solvent was removed under reduced
J 5 13.4, 4.9, 3.3 Hz, 1H), 2.02 (s, 3H), 1.98 (s, 3H), 1.96
0
pressure to give the 2 -azidoethyl 2,3,4-tri-O-acetyl-a-L-fuco-
1
3
(
s, 3H), 1.94 (s, 3H). C-NMR (101 MHz, CDCl ): d 170.53,
3
side 6 (400 mg, 90%).
1
6
70.16, 169.30, 100.66, 72.81, 71.99, 71.11, 68.42, 68.41,
1
1.87, 50.54, 20.65, 20.60, 20.52. HR ESI MS: m/z 440.1267
H-NMR (400 MHz, CDCl ): d 5.31 (dd, J 5 10.2, 3.4 Hz, 1H),
3
1
corresponds to [C H N O ] within 3 ppm. FTIR: ꢀ2100
5.25 (dd, J 5 3.4, 1.3 Hz, 1H), 5.08 (d, J 5 3.7 Hz, 1H), 5.05
(d, J 5 1.2 Hz, 1H), 4.12 (q, J 5 6.5 Hz, 1H), 3.80 (ddd,
J 5 10.8, 6.1, 3.3 Hz, 1H), 3.55 (ddd, J 5 10.6, 7.0, 3.3 Hz,
1
6 23 3 10
2
1
21
cm
(CAN3 stretching vibration), ꢀ1750 cm
(C@O
stretching vibration).
5
186
JOURNAL OF POLYMER SCIENCE, PART A: POLYMER CHEMISTRY 2013, 51, 5184–5193