Article
Biochemistry, Vol. 49, No. 30, 2010 6475
NH), 5.36 (dd, 1 H, J7,8=4.8, J6,7=2.3, H-7), 5.45 (td, 1 H, J4,3a
=
CDCl3) δ: 1.77, 1.87, 1.96, 2.03, 2.14 (5 ꢀ s, 15 H, CH3), 1.96 (dd,
1 H, J3a,3e=13.0, J3a,4=11.5, H-3a), 2.63 (dd, 1 H, J3e,3a=13.0,
J3e,4=4.9, H-3e), 3.68 (s, 3 H, OCH3), 4.08 (dd, 1 H, J6,5=10.7,
J6,7=2.3, H-6), 4.12 (dd, 1 H, J9a,9b=12.6, J9a,8=6.4, H-9a), 4.18
J4,5 = 11.1, J3e,4 = 4.9, H-4), 6.91-7.01 (m, 3 H, H-40, H-50, H-60),
7.08 (m, 1 H, H-30). 13C NMR (150 MHz, CDCl3) δ: 20.80, 20.82
(2C), 20.90, 23.21 (5 ꢀ C, CH3), 37.97 (C-3), 49.21 (C-5), 53.22
(OCH3), 62.09 (C-9), 67.92 (C-7), 68.42 (C-4), 71.67 (C-8), 72.72
(C-6), 100.02 (C-2), 116.85 (d, JC,F = 18.5, C-30), 118.47 (C-50),
124.02 (d, JC,F = 7.0, C-40), 124.54 (d, JC,F = 3.9, C-60), 141.65 (d,
JC,F = 10.7, C-10), 152.99 (d, JC,F = 247.4, C-20), 166.85 (C-1),
170.07, 170.34, 170.45, 170.53, 170.99 (5 ꢀ CdO). Anal. Calcd for
C26H32FNO13: C, 53.33; H, 5.51; N, 2.39. Found: C, 53.06; H, 5.45;
N, 2.22.
(q, 1 H, J5,4 þ J5,6 þ J5,NH = 31.1, H-5), 4.62 (dd, 1 H, J9b,9a
=
12.5, J9b,8 = 2.4, H-9b), 4.94 (ddd, 1 H, J8,9a = 6.4, J8,7 = 5.0,
J8,9b = 2.4, H-8), 5.22 (d, 1 H, JNH,5=10.1, NH), 5.36 (dd, 1 H,
J7,8 = 5.0, J6,7 = 2.3, H-7), 5.45 (m, 1 H, H-4), 6.85 (m, 2 H, H-20,
H-60), 6.87 (m, 2 H, H-30, H-50). 13C NMR (150 MHz, CDCl3) δ:
20.94, 21.00, 21.01, 21.12, 23.43 (5 ꢀ C, CH3), 38.67 (C-3), 49.49
(C-5), 53.37 (OCH3), 62.15 (C-9), 68.10 (C-7), 68.61 (C-4), 71.80
(C-8), 72.51 (C-6), 99.63 (C-2), 116.49 (d, JC,F = 22.9, C-30, C-50),
Methyl [3-Fluorophenyl (5-Acetamido-4,7,8,9-tetra-O-
acetyl-3,5-dideoxy-D-glycero-β-D-galacto-non-2-ulopyrano-
118.40 (d, JC,F = 8.2, C-20, C-60), 150.14 (s, C-10), 158.66 (d, JC,F
=
syl)]onate (2c). A mixture of activated 3 A molecular sieves (5 g)
242.1, C-40) 167.30 (C-1), 170.27, 170.45, 170.71, 171.23 (5 ꢀ
CdO). Anal. Calcd for C26H32FNO13: C, 53.33; H, 5.51; N,
2.39. Found: C, 53.09; H, 5.49; N, 2.24.
˚
and peracetylated sialosyl fluoride 4 (400 mg, 0.81 mmol) was
dried under vacuum for 30 min. To the resultant solid, 3-fluor-
ophenol (482 mg, 4.30 mmol) and dry CH2Cl2 (30 mL) were added
under a N2 atmosphere, and the mixture was then stirred for 1 h at
Methyl [2,5-Difluorophenyl (5-Acetamido-4,7,8,9-tetra-
O-acetyl-3,5-dideoxy-D-glycero-β-D-galacto-non-2-ulopyra-
˚
rt. Then, BF3 OEt2 (0.7 mL, 5.80 mmol) in CH2Cl2 (4 mL) was
nosyl)]onate (2f). To activated 3 A molecular sieves (5 g) was
3
added, and the mixture was stirred overnight under a N2 atmo-
sphere at room temperature. The resultant mixture was filtered
through Celite and washed thoroughly with CH2Cl2. The com-
bined filtrates were washed with saturated NaHCO3 (150 mL),
water (150 mL), and brine (150 mL), and the resulting solution was
dried over anhydrous Na2SO4. After evaporating the solvent under
reduced pressure, a yellow syrup was obtained, which crystallized
from diethyl ether to give a white powder (280 mg, 60% yield). mp
194-195 °C; [R]20D = -38.5 (0.12, CH2Cl2). 1H NMR (600 MHz,
CDCl3) δ: 1.77, 1.87, 2.03, 2.04, 2.14 (5 ꢀ s, 15 H, CH3), 1.98 (t,
added peracetylated sialosyl fluoride 4 (400 mg, 0.81 mmol), and
the resulting solid mixture was dried under vacuum for 30 min. To
this mixture, a solution of 2,5-difluorophenol (482 mg, 4.30 mmol)
in dry CH2Cl2 (30 mL) was added under a N2 atmosphere, and the
mixture was then stirred for 1 h. Then, BF3 OEt2 (0.7 mL, 5.8
3
mmol) in CH2Cl2 (4 mL) was added, and the mixture was stirred
overnight under a N2 atmosphere at room temperature. The resul-
tant mixture was filtered through Celite and washed thoroughly
with CH2Cl2. The combined filtrates were washed with saturated
NaHCO3 (150 mL), water (150 mL), and brine (150 mL), and this
solution was dried over anhydrous Na2SO4. After evaporating the
solvent under reduced pressure, a yellow syrup was obtained,
which crystallized from diethyl ether to give a white powder (157
mg, 33% yield). mp 167-168 °C; [R]20D = -44.0 (0.10, CH2Cl2).
1H NMR (600 MHz, CDCl3) δ: 1.86, 1.92, 2.02, 2.03, 2.14 (5 ꢀ s,
15 H, CH3), 2.03 (dd, 1 H, J3a,3e = 13.1, J3a,4 = 11.5, H-3a), 2.71
(dd, 1 H, J3e,3a = 13.3, J3e,4 = 5.0, H-3e), 3.77 (s, 3 H, OCH3), 4.07
(m, 2 H, H-6 and H-9a), 4.24 (q, 1 H, J5,4 þ J5,6 þ J5,NH = 31.3,
H-5), 4.67 (dd, 1 H, J9b,9a = 12.5, J9b,8 = 2.3, H-9b), 4.84 (m, 1 H,
H-8), 5.31 (d, 1 H, JNH,5 =10.3, NH), 5.32 (dd, 1 H, J7,8 =6.1,
J6,7 = 2.5, H-7), 5.45 (td, 1 H, J4,3e = 5.0, J4,3a = J4,5 = 11.3, H-4),
6.70 (m, 1 H, H-40), 6.77 (m, 1 H, H-60), 7.06 (m, 1 H, H-30). 13C
NMR (150 MHz, CDCl3) δ: 21.08, 21.17, 21.20, 21.27, 23.55 (5 ꢀ
C, CH3), 38.29 (C-3), 49.46 (C-5), 53.87 (OCH3), 62.36 (C-9), 68.55
(C-7), 68.70 (C-4), 72.87 (C-8), 73.81 (C-6), 100.47 (C-2), 106.45 (d,
JC,F = 25.1, C-60), 110.10 (dd, JC,F = 24.4 and 7.1, C-40), 117.50
(dd, JC,F = 21.1, JC,F = 9.8, C-30), 142.24 (m, C-10), 149.65 (dd,
JC,F = 243.9 and 3.2, C-20), 158.45 (dd, JC,F = 244.3 and 2.3,
C-50), 166.91 (C-1), 170.53, 170.76, 171.14, 171.16, 171.35 (5 ꢀ
CdO). Anal. Calcd for C26H31F2NO13: C, 51.74; H, 5.18; N, 2.32.
Found: C, 51.56; H, 5.13; N, 2.09.
1 H, J3a,3e=J3a,4=11.7, H-3a), 2.62 (dd, 1 H, J3e,3a=13.0, J3e,4
5.0, H-3e), 3.73 (s, 3 H, OCH3), 4.04 (dd, 1 H, J6,5 = 10.7, J6,7
=
=
2.4, H-6), 4.12 (dd, 1 H, J9a,9b = 12.5, J9a,8 = 6.6, H-9a), 4.20 (q, 1
H, J5,4 þ J5,6 þ J5,NH =31.4, H-5), 4.66 (dd, 1 H, J9b,9a =12.6,
J9b,8 = 2.4, H-9b), 4.90 (m, H-8), 5.23 (d, 1 H, JNH,5 = 10.2, NH),
5.34 (dd, 1 H, J7,8 = 4.6, J6,7 = 2.3, H-7), 5.44 (td, 1 H, J4,3a
=
J4,5 =11.1, J4,3e = 4.9, H-4), 6.66-6.77 (m, 3 H, H-20, H-40, H-60),
7.18 (m, 1 H, H-50). 13C NMR (150 MHz, CDCl3) δ: 20.66, 20.70,
20.76, 20.87, 23.17 (5 ꢀ C, CH3), 38.44 (C-3), 49.16 (C-5), 53.28
(OCH3), 62.01 (C-9), 67.93 (C-7), 68.30 (C-4), 71.88 (C-8), 72.59
(C-6), 99.22 (C-2), 104.50 (d, JC,F = 25.4, C-20), 109.99 (d, JC,F
=
21.1, C-40), 112.34 (d, JC,F=2.9, C-60), 130.79 (d, JC,F=9.8, C-50),
154.90 (d, JC,F = 10.8, C-10), 163.16 (d, JC,F = 247.7, C-300), 167.00
(C-1), 170.07, 170.23, 170.45, 170.65, 171.98 (5 ꢀ CdO). Anal.
Calcd for C26H32FNO13: C, 53.33; H, 5.51; N, 2.39. Found: C,
53.26; H, 5.66; N, 2.17.
Methyl [4-Fluorophenyl (5-Acetamido-4,7,8,9-tetra-O-
acetyl-3,5-dideoxy-D-glycero-β-D-galacto-non-2-ulopyrano-
˚
syl)]onate (2d). To activated 3 A molecular sieves (5 g) was
added peracetylated sialosyl fluoride 4 (400 mg, 0.81 mmol), and
the mixture was dried under vacuum for 30 min. To the resultant
mixture was added 4-fluorophenol (482 mg, 4.3 mmol) and dry
CH2Cl2 (30 mL) under N2 atmosphere, and the mixture was then
Methyl [3,5-Difluorophenyl (5-Acetamido-4,7,8,9-tetra-
O-acetyl-3,5-dideoxy-D-glycero-β-D-galacto-non-2-ulopyra-
˚
stirred for 1 h. Then, BF3 OEt2 (0.7 mL, 5.8 mmol) in CH2Cl2 (4
nosyl)]onate (2h). To activated 3 A molecular sieves (5 g) was
3
mL) was added, and the mixture was stirred overnight under N2
atmosphere at room temperature. The resultant mixture was
filtered through Celite and washed thoroughly with CH2Cl2. The
combined filtrates were washed with saturated NaHCO3 (150 mL),
water (150 mL), and brine (150 mL), and the resulting solution was
dried over anhydrous Na2SO4. After evaporating the solvent under
reduced pressure, a yellow syrup was obtained, which crystallized
from diethyl ether to give a white powder (234 mg, 50% yield). mp
202-203 °C; [R]20D = -45.2 (0.22, CH2Cl2). 1H NMR (600 MHz,
added peracetylated sialosyl fluoride 4 (400 mg, 0.81 mmol), and
the mixture was dried under vacuum for 30 min. To the result-
ing mixture, 3,5-difluorophenol (560 mg, 4.30 mmol) and dry
CH2Cl2 (30 mL) were added under a N2 atmosphere, and the
mixture was then stirred for 1 h. Subsequently, a solution of
BF3 OEt2 (0.7 mL, 5.81 mmol) in CH2Cl2 (4 mL) was added, and
3
the mixture was stirred overnight under N2 atmosphere at room
temperature. The resultant mixture was filtered through Celite
and washed thoroughly with CH2Cl2. The combined filtrates