Ganglioside GQ1b
6′i), 1.67 (t, 1 H, NHCOCH2), 1.63 (t, 1 H, Jgem ) J3ax,4 ) 12.2
Hz, H-3ax-g), 1.34 (m, 1 H, NHCOCH2), 1.26 (m, 52 H, 26 CH2),
0.87 (2 t, 6 H, 2 Me); 13C NMR (100 MHz, CDCl3) δ 172.4, 170.8,
170.6, 170.5, 170.4, 170.4, 170.3, 170.3, 170.1, 170.1, 169.7, 169.6,
169.5, 167.3, 167.1, 166.3, 165.9, 165.8, 165.6, 165.4, 165.2, 165.0,
164.9, 164.7, 164.1, 164.0, 158.9, 158.7, 136.9, 133.1, 133.0, 132.9,
132.6, 130.1, 130.1, 130.0, 129.8, 129.6, 129.5, 129.4, 129.4, 129.3,
128.9, 128.8, 128.4, 128.3, 128.1, 124.6, 113.4, 113.3, 101.3, 100.8,
100.3, 99.6, 99.4, 98.9, 96.8, 95.7, 80.1, 77.2, 76.4, 75.1, 74.3, 73.9,
73.8, 73.4, 73.1, 72.8, 72.5, 72.1, 71.8, 71.5, 71.3, 71.2, 71.1, 70.8,
70.7, 70.3, 69.8, 69.4, 69.3, 69.2, 68.7, 68.5, 68.2, 67.8, 67.1, 66.8,
66.6, 63.3, 62.0, 61.7, 55.0, 54.6, 53.0, 52.2, 50.2, 48.9, 48.7, 38.8,
38.2, 36.9, 36.2, 35.4, 32.5, 32.1, 31.7, 29.8, 29.5, 29.4, 29.3, 29.2,
29.1, 29.0, 28.8, 25.3, 22.9, 22.8, 22.6, 22.5, 20.6, 20.6, 20.5, 20.4,
20.2, 20.1, 14.0; HRMS (ESI) m/z found [M + 2Na]2+ 2068.8101,
75.6, 74.8, 74.2, 74.0, 73.6, 73.3, 73.1, 72.5, 72.1, 72.0, 71.6, 71.4,
71.0, 70.9, 70.4, 70.1, 69.9, 69.5, 69.4, 69.4, 69.0, 68.7, 68.6, 68.5,
67.9, 67.7, 67.2, 67.0, 66.7, 63.7, 62.1, 62.0, 61.8, 54.0, 53.2, 52.4,
51.2, 49.1, 48.9, 48.8, 38.8, 38.3, 36.4, 35.4, 32.2, 31.9, 29.7, 29.6,
29.5, 29.3, 29.2, 29.2, 25.4, 23.1, 23.1, 23.0, 22.6, 20.8, 20.7, 20.6,
20.3, 14.1; HRMS (ESI) m/z found [M + 2Na]2+ 2031.8146,
C
209H256N6O73 calcd for [M + 2Na]2+ 2031.8149.
2-(Trimethylsilyl)ethyl [Methyl 5-acetamido-8-O-(5-aceta-
mido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-r-D-galacto-
2-nonulopyranosylono-1′,9-lactone)-4,7-di-O-acetyl-3,5-dideoxy-
D-glycero-r-D-galacto-2-nonulopyranosylonate]-(2f3)-2,4,6-tri-
O-benzoyl-ꢀ-D-galactopyranosyl-(1f3)-2-acetamido-4,6-di-O-
benzoyl-2-deoxy-ꢀ-D-galactopyranosyl-(1f4)-{[methyl 5-
acetamido-8-O-(5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-
D-glycero-r-D-galacto-2-nonulopyranosylono-1′,9-lactone)-4,7-
di-O-acetyl-3,5-dideoxy-D-glycero-r-D-galacto-2-nonulopyra-
nosylonate]-(2f3)}-2,6-di-O-benzoyl-ꢀ-D-galactopyranosyl-(1f4)-
2-O-benzoyl-3,6-di-O-benzyl-ꢀ-D-glucopyranoside (42). To a mixture
of 20 (189 mg, 0.0613 mmol) and 38 (52 mg, 0.0919 mmol) in CH2Cl2
(1.5 mL) was added 4 Å molecular sieves (AW-300) (250 mg) at room
temperature. After stirring for 2 h and then cooling to 0 °C, TMSOTf
(1.1 µL, 6.13 µmol) was added to the mixture. After stirring for 2 h
at 0 °C as the reaction was monitored by TLC (PhMe/MeOH ) 4:1),
the reaction was quenched by saturated NaHCO3 (aq) and filtered
through a Celite pad, and the pad was washed with CHCl3. The
combined filtrate and washings were washed with brine, dried over
Na2SO4, and concentrated. The residue was purified by flash column
chromatography using PhMe/MeOH (6:1) as the eluent to give 42 (135
mg, 63%): [R]D ) -0.6° (c 1.5, CHCl3); 1H NMR (500 MHz, CDCl3)
δ 8.13-6.89 (m, 50 H, 10 Ph), 5.95 (br s, 1 H, H-4d), 5.85 (br d, 1
H, NH-d), 5.70 (d, 1 H, J3,4 ) 3.4 Hz, H-4e), 5.63 (d, 1 H, J5,NH ) 9.0
Hz, NH-b), 5.54 (dt, 1 H, J3eq,4 ) 5.3 Hz, J3ax,4 ) 12.2 Hz, J4,5 ) 10.2
C
211H258N6O76 calcd for [M + 2Na]2+ 2068.8146.
[Methyl 5-acetamido-8-O-(5-acetamido-4,7,8,9-tetra-O-acetyl-
3,5-dideoxy-D-glycero-r-D-galacto-2-nonulopyranosylono-1′,9-
lactone)-4,7-di-O-acetyl-3,5-dideoxy-D-glycero-r-D-galacto-2-
nonulopyranosylonate]-(2f3)-2,4,6-tri-O-benzoyl-ꢀ-D-
galactopyranosyl-(1f3)-2-acetamido-4,6-di-O-benzoyl-2-deoxy-
ꢀ-D-galactopyranosyl-(1f4)-{[methyl 5-acetamido-8-O-(5-acet-
amido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-r-D-galacto-
2-nonulopyranosylono-1′,9-lactone)-4,7-di-O-acetyl-3,5-dideoxy-
D-glycero-r-D-galacto-2-nonulopyranosylonate]-(2f3)}-2,6-di-O-
benzoyl-ꢀ-D-galactopyranosyl-(1f4)-2-O-benzoyl-3,6-di-O-benzyl-
ꢀ-D-glucopyranosyl-(1f1)-(2S,3R,4E)-3-O-benzyl-2-
octadecanamido-4-octadecene-1,3-diol (41). To a mixture of 20
(148 mg, 0.0480 mmol) and 37 (79 mg, 0.0720 mmol) in CH2Cl2
(1.0 mL) was added 4 Å molecular sieves (AW-300) (180 mg) at
room temperature. After stirring for 2 h and then cooling to 0 °C,
TMSOTf (1.0 µL, 5.52 µmol) was added to the mixture. After
stirring for 2 h at 0 °C as the reaction was monitored by TLC
(PhMe/MeOH ) 4:1), additional TMSOTf (1.0 µL, 5.52 µmol) was
added to the mixture. After the stirring was continued for 24 h, the
reaction was quenched by saturated NaHCO3 (aq) and filtered
through a Celite pad, and the pad was washed with CHCl3. The
combined filtrate and washings were washed with brine, dried over
Na2SO4 and concentrated. The resulting residue was purified by
flash column chromatography (PhMe/MeOH ) 9:1 to 8:1) to give
Hz, H-4g), 5.45 (d, 1 H, J5,NH ) 8.7 Hz, NH-g), 5.43 (d, 1 H, J5,NH
)
8.5 Hz, NH-a), 5.34 (m, 1 H, H-4b), 5.32 (dd, 3 H, J6,7 ) 2.1 Hz, J7,8
) 9.0 Hz, J1,2 ) 7.8 Hz, H-7b, 7g, and 2e), 5.27 (d, 1 H, NH-f), 5.24
(t, 1 H, J1,2 ) 7.8 Hz, J2,3 ) 9.5 Hz, H-2c), 5.21 (d, 1 H, J1,2 ) 8.5
Hz, H-1d), 5.17 (m, 3 H, J1,2 ) 7.8 Hz, J7,8 ) 9.0 Hz, H-2h, 8b, and
8g), 5.08 (m, 1 H, H-4f), 5.01 (dd, 1 H, J6,7 ) 1.7 Hz, J7,8 ) 11.2 Hz,
H-7a), 4.96 (br dt, 1 H, H-4a), 4.86 and 4.62 (2 d, 2 H, Jgem ) 10.9
Hz, PhCH2), 4.84 (dd, 1 H, J6,7 ) 2.9 Hz, J7,8 ) 9.2 Hz, H-7f), 4.75
(br dd, 1 H, H-3d), 4.67 (d, 1 H, J1,2 ) 7.8 Hz, H-1c), 4.63 (m, 1 H,
J7,8 ) 9.2 Hz, H-8f), 4.55 (br d, 1 H, H-6c), 4.50 and 4.28 (2 d, 2 H,
Jgem ) 12.2 Hz, PhCH2), 4.42 (d, 3 H, J1,2 ) 7.8 Hz, H-1e, 3e, and
1h), 4.33-4.19 (m, 10 H, H-9′b, 9′g, 9′a, 9′f, 8a, 6e, 6′e, 6′d, 6d, and
5b), 4.11 (q, 1 H, J4,5 ) 10.2 Hz, J5,6 ) 10.4 Hz, J5,NH ) 8.7 Hz,
H-5g), 4.06-3.97 (m, 12 H, H-5f, 6b, 5a, 3c, 9a, 9b, 4c, 4h, 6′c, 9b,
5e, and 5d), 3.92 (dd, 1 H, J5,6 ) 10.4 Hz, J6,7 ) 2.1 Hz, H-6g), 3.87
(m, 1 H, OCH2CH2SiMe3), 3.85-3.72 (m, 8 H, H-6a, 6f, 3h, 9f, 2d,
and COOMe-a), 3.56 (m, 2 H, Jgem ) 10.7 Hz, H-6′h and 5c), 3.50
(dd, 1 H, Jgem ) 10.7 Hz, H-6h), 3.41 (m, 1 H, OCH2CH2SiMe3),
3.35 (m, 1 H, H-5h), 3.22 (s, 3 H, COOMe-f), 2.58 (br dd, 1 H, H-3eq-
b), 2.50 (dd, 1 H, J3eq,4 ) 5.3 Hz, Jgem ) 12.2 Hz, H-3eq-g), 2.27 (br
dd, 1 H, H-3eq-a), 2.11-1.80 (m, 55 H, 17 Ac, H-3ax-b, 3ax-a, 3eq-
f, and 3ax-f), 1.63 (t, 1 H, J3ax,4 ) Jgem ) 12.2 Hz, H-3ax-g), 0.81 (m,
2 H, OCH2CH2SiMe3), -0.12 (s, 9 H, OCH2CH2SiMe3); 13C NMR
(100 MHz, CDCl3) δ 170.9, 170.6, 170.5, 170.5, 170.5, 170.4, 170.3,
170.2, 170.2, 169.8, 169.7, 169.7, 169.6, 167.4, 167.2, 166.1, 165.9,
165.9, 165.7, 165.4, 164.9, 164.6, 164.1, 138.2, 138.2, 133.2, 133.1,
133.1, 132.9, 132.8, 132.7, 130.2, 130.1, 129.9, 129.9, 129.7, 129.6,
129.6, 129.5, 129.5, 129.4, 128.9, 128.5, 128.4, 128.4, 128.3, 128.2,
128.2, 127.9, 127.8, 127.7, 127.4, 127.1, 101.2, 100.4, 100.1, 99.8,
99.5, 99.0, 97.1, 96.0, 80.8, 77.2, 76.4, 76.2, 74.7, 74.0, 73.8, 73.2,
73.1, 72.5, 72.1, 72.0, 71.6, 71.3, 70.9, 70.4, 69.8, 69.5, 69.3, 69.2,
69.0, 68.7, 68.5, 68.4, 68.0, 67.2, 67.1, 67.0, 66.9, 66.7, 63.5, 62.1,
62.0, 61.8, 54.3, 53.1, 52.3, 49.1, 48.9, 38.7, 38.2, 35.5, 35.4, 29.6,
23.0, 23.0, 22.9, 22.7, 20.7, 20.7, 20.6, 20.6, 20.6, 20.5, 20.3, 20.2,
17.8, -1.5; HRMS (ESI) m/z found [M + 2Na]2+ 1763.0599,
1
41 (140 mg, 73%): [R]D ) -2.5° (c 1.0, CHCl3); H NMR (600
MHz, CDCl3) δ 8.01-6.89 (m, 55 H, 11 Ph), 5.97 (near s, 1 H,
H-4d), 5.69 (d, 1 H, J3,4 ) 2.7 Hz, H-4e), 5.54 (m, 4 H, H-4g, 5i,
and 2 NH), 5.36 (m, 5 H, H-4b, 7b, and 3 NH), 5.32 (dd, 1 H, J6,7
) 2.0 Hz, J7,8 ) 8.2 Hz, H-7g), 5.19 (m, 7 H, H-8b, 2e, 2c, 1d, 2h,
8g, and 4i), 5.08 (m, 1 H, H-4f), 5.01 (near d, 1 H, J7,8 ) 8.9 Hz,
H-7a), 4.98 (m, 1 H, H-4a), 4.89 (d, 1 H, Jgem ) 10.9 Hz, PhCH2),
4.83 (near dd, 1 H, J7,8 ) 9.6 Hz, H-7f), 4.62 (m, 5 H, H-3d, 8f,
6c, 6′c, and PhCH2), 4.60 (d, 1 H, J1,2 ) 7.5 Hz, H-1c), 4.49 and
4.28 (2 d, 2 H, Jgem ) 11.6 Hz, PhCH2), 4.49 and 4.17 (2 d, 2 H,
Jgem ) 11.6 Hz, PhCH2), 4.44 (m, 2 H, H-1e and 3e), 4.35 (d, 1 H,
J1,2 ) 7.5 Hz, H-1h), 4.31-4.20 (m, 8 H, H-9′g, 9′b, 9′f, 9f, 5b,
9′a, 1′i, and 8a), 4.13-3.97 (m, 10 H, H-6b, 5a, 5g, 4h, 4c, 3c, 5f,
2i, 9b, and 9g), 3.89 (dd, 1 H, J5,6 ) 10.3 Hz, J6,7 ) 2.0 Hz, H-6g),
3.84 (m, 2 H, H-6a and 6f), 3.78 (m, 5 H, H-3h, 2d, and COOMe-
a), 3.71 (m, 2 H, H-3i and 9a), 3.61 (br t, 1 H, H-5c), 3.53 (br dd,
1 H, Jgem ) 10.9 Hz, H-6′h), 3.46 (br d, 1 H, Jgem ) 10.9 Hz,
H-6h), 3.35 (br dd, 1 H, H-1i), 3.26 (m, 1 H, H-5h), 3.23 (s, 3 H,
COOMe-f), 2.57 (br dd, 1 H, H-3eq-b), 2.48 (dd, 1 H, H-3eq-g),
2.22 (m, 1 H, H-3eq-a), 2.11-1.82 (13 s and m, 57 H, 17 Ac,
H-3eq-f, 3ax-f, 3ax-a, 3ax-b, 6i, and 6′i), 1.61 (m, 3 H, H-3ax-g,
NHCOCH2), 1.26 (m, 52 H, 26 CH2), 0.87 (t, 6 H, 2 Me); 13C
NMR (125 MHz, CDCl3) δ 172.3, 170.8, 170.7, 170.6, 170.6, 170.5,
170.4, 170.4, 170.2, 169.8, 169.8, 169.7, 167.5, 167.3, 166.2, 166.0,
165.8, 165.4, 165.2, 164.6, 164.2, 164.1, 138.5, 138.2, 138.0, 137.0,
133.4, 133.3, 133.1, 133.1, 133.0, 132.8, 130.3, 130.0, 129.9, 129.8,
129.8, 129.7, 129.6, 129.6, 129.5, 129.5, 129.3, 128.6, 128.5, 128.5,
128.4, 128.3, 128.1, 128.0, 128.0, 127.9, 127.6, 127.5, 127.4, 127.3,
127.2, 101.3, 100.2, 100.2, 99.9, 99.6, 99.0, 97.1, 96.1, 80.3, 79.0,
C
171H193N5O71Si calcd for [M + 2Na]2+ 1763.0599.
J. Org. Chem. Vol. 74, No. 8, 2009 3021