The Journal of Organic Chemistry
Note
decanted, and this step was repeated with fresh ice-cold diethyl ether.
Finally, the white crude product was dried, first under a flow of
nitrogen for a short amount of time and then under vacuum.
The crude product was then purified by high-performance liquid
chromatography using a semiprep C18 column [Luna 5 μm C18(2),
100 Å (250 mm × 10 mm)] and lyophilized to give 17a, 17b, 18a,
and 18b as white solids (mixture of α and β anomeric isomers) (70−
85 mg): buffer A, 98% water, 2% acetonitrile, and 0.06%
trifluoroacetic acid; buffer B, 20% water, 80% acetonitrile, and
0.04% trifluoroacetic acid; flow rate of 3 mL/min; detection via dual
absorbance detection at 214 and 254 nm; gradient of 100% A and 0%
B from 0 to 4 min, from 100% A and 0% B to 80% A and 20% B from
4 to 10 min, from 80% A and 20% B to 30% A and 70% B from 10 to
40 min, from 30% A and 70% B to 0% A and 100% B from 40 to 42
min, of 0% A and 100% B from 42 to 47 min, from 0% A and 100% B
to 100% A and 0% B from 47 to 50 min, and of 100% A and 0% B
from 50 to 60 min.
2Hγ, 2Hγ′ (D-Glu)), 2.21−2.15 (m, 2H, Hβ, Hβ′ (D-Glu)), 2.01−1.85
(m, 8H, Hβ, Hβ′ (D-Glu), -COCH3 (×2)) 1.83−1.64 (m, 6H, 2Hβ,
2Hβ′ (L-Lys), 2Hδ′ (L-Lys)), 1.51−1.31 (m, 21H, 2Hδ (L-Lys), 2Hγ,
2Hγ′ (L-Lys), -CH3, -CH3′ (L-Ala), -CH3 (D-Ala), -COCH(CH3)O-
(×2)); 13C{1H} NMR (151 MHz, deuterium oxide) δ 175.7, 175.6,
175.5, 174.9, 174.8, 174.7, 174.6, 174.5, 174.49, 174.44, 174.0, 173.74,
173.72, 136.9, 128.6, 128.49, 128.45, 128.3, 95.7, 79.56, 79.55, 77.67,
77.63, 72.0, 69.5, 69.4, 69.09, 69.04, 60.3, 54.1, 53.2, 53.1, 52.7, 51.8,
51.7, 49.9, 49.59, 49.54, 39.1, 38.8, 31.3, 31.1, 30.1, 29.9, 27.7, 26.6,
26.5, 26.3, 22.2, 22.0, 21.8, 18.5, 18.4, 16.7, 16.5; HRMS (ESI) m/z
[M + H]+ calcd for C67H102N11O26 1476.6997, found 1476.6973.
18b: 1H NMR (600 MHz, deuterium oxide) δ 7.45−7.38 (m, 10H,
aromatic(OBn)), 4.90 (d, J = 3.7 Hz, 2H, anomeric H-1, anomeric H-
1′), 4.75 (d, J = 12.0, 2H, -OCHHPh (×2)), 4.54 (d, J = 12.0 Hz, 2H,
-OCHHPh (×2)), 4.30−4.19 (m, 9H, Hα, Hα′ (D-Gln), Hα, Hα′ (L-
Ala), Hα, Hα′ (L-Lys), Hα (D-Ala), -COCH(Me)O- (×2)), 3.97−3.95
(m, 2H, GlcNAc ring H-2,2′), 3.85−3.75 (m, 6H, GlcNAc ring H-
5,5′,6,6′), 3.72−3.69 (m, 2H, GlcNAc ring H-3,3′), 3.61−3.58 (m,
2H, GlcNAc ring H-4,4′), 3.23−3.18 (m, 1H, Hε (L-Lys)), 3.16−3.11
(m, 1H, Hε (L-Lys)), 2.98 (t, J = 7.7 Hz, 2H, 2Hε′ (L-Lys)), 2.40−2.31
(m, 4H, 2Hγ, 2Hγ′ (D-Glu)), 2.20−2.12 (m, 2H, Hβ, Hβ′ (D-Glu)),
1.99−1.89 (m, 8H, Hβ, Hβ′ (D-Glu), -COCH3 (×2)), 1.85−1.65 (m,
6H, 2Hβ, 2Hβ′ (L-Lys), 2Hδ′ (L-Lys)), 1.52−1.32 (m, 21H, 2Hδ (L-
Lys), 2Hγ, 2Hγ′ (L-Lys), -CH3, -CH3′ (L-Ala), CH3 (D-Ala),
-COCH(CH3)O- (×2)); 13C{1H} NMR (151 MHz, deuterium
oxide) δ 175.87, 175.83, 175.80, 175.7, 175.6, 174.99, 174.94,
174.92, 174.8, 174.5, 174.0, 173.75, 173.73, 136.9, 128.7, 128.5, 128.4,
128.3, 95.8, 79.79, 79.76, 77.7, 77.6, 71.9, 69.52, 69.50, 68.9, 68.8,
60.3, 54.0, 53.23, 53.22, 52.8, 52.7, 52.6, 49.9, 49.77, 49.73, 39.1, 38.8,
31.4, 31.2, 30.1, 29.9, 27.8, 26.9, 26.7, 26.3, 22.2, 22.0, 21.8, 18.6,
18.5, 16.6, 16.5; HRMS (ESI) m/z [M + H]+ calcd for C67H104N13O24
1474.7317, found 1474.7288.
17a: 1H NMR (600 MHz, deuterium oxide) δ 7.45−7.38 (m, 10H,
aromatic(OBn)), 4.91−4.90 (m, 2H, anomeric H-1, anomeric H-1′),
4.76−4.73 (m, 2H, -OCHHPh (×2)), 4.54 (d, J = 12.0 Hz, 2H,
-OCHHPh (×2)), 4.40−4.34 (m, 2H, Hα, Hα′ (D-Glu)), 4.31−4.25
(m, 5H, Hα, Hα′ (L-Ala), -COCH(Me)O- (×2), Hα (L-Lys)), 4.17
(dd, J = 8.7, 5.8 Hz, 1H, Hα′ (L-Lys)), 3.96−3.93 (m, 2H, GlcNAc
ring H-2,2′), 3.85−3.76 (m, 6H, GlcNAc ring H-5,5′,6,6′), 3.72−3.69
(m, 2H, GlcNAc ring H-3,3′), 3.61−3.58 (m, 2H, GlcNAc ring H-
4,4′), 3.25−3.20 (m, 1H, Hε (L-Lys)), 3.16−3.11 (m, 1H, Hε (L-
Lys)), 2.97 (t, J = 7.7 Hz, 2H, 2Hε′ (L-Lys)), 2.39−2.30 (m, 4H, 2Hγ,
2Hγ′ (D-Glu)), 2.24−2.16 (m, 2H, Hβ, Hβ′ (D-Glu)), 2.03−1.93 (m,
2H, Hβ, Hβ′ (D-Glu)), 1.89 (s, 3H, -COCH3), 1.88 (s, 3H, -COCH3),
1.85−1.75 (m, 2H, Hβ, Hβ′ (L-Lys)), 1.72−1.63 (m, 4H, Hβ, Hβ′ (L-
Lys), 2Hδ′ (L-Lys)), 1.53−1.46 (m, 2H, 2Hδ (L-Lys)), 1.43−1.32 (m,
16H, 2Hγ, 2Hγ′ (L-Lys), -CH3, -CH3′ (L-Ala), -COCH(CH3)O-
(×2)); 13C{1H} NMR (151 MHz, deuterium oxide) δ 175.7, 175.6,
175.5, 174.8, 174.77, 174.72, 174.70, 174.6, 174.5, 173.78, 173.74,
173.73, 136.9, 136.98, 136.96, 128.6, 128.5, 128.4, 128.33, 128.31,
95.7, 79.6, 79.5, 77.67, 77.63, 72.02, 72.00, 69.52, 69.50, 69.0, 68.9,
60.3, 54.0, 53.2, 53.1, 52.7, 51.8, 49.6, 49.5, 39.1, 38.8, 31.3, 31.2,
30.4, 30.0, 27.7, 26.7, 26.5, 26.2, 22.3, 22.1, 21.8, 18.5, 18.4, 16.73,
16.70; HRMS (ESI) m/z [M + H]+ calcd for C64H97N10O25
1405.6626, found 1405.6605.
16a. In a round-bottom flask, 17a (15 mg, 0.01 mmol, 1.0 equiv)
was dissolved in 2 mL of water and 100 μL of acetic acid was added
followed by 10 mg of Pd/C (20 wt % loading). The flask was then
purged with hydrogen and allowed to stir for 24 h under hydrogen
(balloon). Removal of benzyl protecting groups was confirmed by
LC-MS. Next, the Pd/C catalyst was filtered by being passed through
a 0.22 μm filter, and the filtrate was lyophilized to give 16a (12 mg,
94% yield) as a white solid [as a mixture of anomeric α and β isomers
17b: 1H NMR (600 MHz, deuterium oxide) δ 7.45−7.38 (m, 10H,
aromatic(OBn)), 4.90 (d, J = 3.6 Hz, 2H, anomeric H-1, anomeric H-
1′), 4.75 (d, J = 12.0 Hz, 2H, -OCHHPh (×2)), 4.54 (d, J = 12.0 Hz,
2H, -OCHHPh (×2)), 4.30−4.22 (m, 7H, Hα, Hα′ (D-Gln), Hα, Hα′
(L-Ala), -COCH(Me)O- (×2), Hα (L-Lys)), 4.17 (dd, J = 8.6, 5.9 Hz,
1H, Hα′ (L-Lys)), 3.97−3.94 (m, 2H, GlcNAc ring H-2,2′), 3.85−3.75
(m, 6H, GlcNAc ring H-5,5′,6,6′), 3.72−3.68 (m, 2H, GlcNAc ring
H-3,3′), 3.61−3.58 (m, 2H, GlcNAc ring H-4,4′), 3.24−3.20 (m, 1H,
Hε (L-Lys)), 3.17−3.13 (m, 1H, Hε (L-Lys)), 2.97 (t, J = 7.7 Hz, 2H,
2Hε′ (L-Lys)), 2.40−2.31 (m, 4H, 2Hγ, 2Hγ′ (D-Gln)), 2.20−2.14 (m,
2H, Hβ, Hβ′ (D-Gln)), 2.00−1.88 (m, 8H, Hβ, Hβ′ (D-Gln), -COCH3
(×2)), 1.87−1.75 (m, 2H, Hβ, Hβ′ (L-Lys)), 1.74−1.64 (m, 4H, Hβ,
Hβ′ (L-Lys), 2Hδ′ (L-Lys)), 1.53−1.48 (m, 2H, 2Hδ (L-Lys)), 1.45−
1.30 (m, 16H, 2Hγ, 2Hγ′ (L-Lys), -CH3, -CH3′ (L-Ala), -COCH-
(CH3)O- (×2)); 13C{1H} NMR (151 MHz, deuterium oxide) δ
175.87, 175.83, 175.82, 175.78, 175.71, 174.9, 174.87, 174.82, 173.75,
173.73, 136.9, 128.7, 128.5, 128.4, 128.3, 95.8, 79.8, 79.7, 77.6, 71.9,
69.5, 68.9, 68.8, 60.3, 54.0, 53.24, 53.22, 52.79, 52.73, 52.5, 49.79,
49.72, 39.1, 38.9, 31.4, 31.3, 30.4, 29.9, 27.7, 26.8, 26.7, 26.2, 22.3,
22.1, 21.8, 18.6, 18.5, 16.54, 16.52; HRMS (ESI) m/z [M + H]+ calcd
for C64H99N12O23 1403.6946, found 1403.6921.
(1:0.25)] (protium counts for the major isomer are reported): H
1
NMR (600 MHz, deuterium oxide) δ 5.16 (d, J = 3.4 Hz, 2H,
anomeric H-1(α), anomeric H-1′(α)), 4.67 (d, J = 8.5 Hz, 2H,
anomeric H-1(β), anomeric H-1′(β)), 4.40−4.18 (m, 8H, Hα, Hα′ (D-
Glu), Hα, Hα′ (L-Ala), -COCH(Me)O- (×2), Hα, Hα′ (L-Lys)), 3.98−
3.95 (m, 2H, GlcNAc ring H-2,2′(α)), 3.93−3.74 (m, 6H, GlcNAc
ring H-5,5′,6,6′(α), H-2,2′,5,5′,6,6′(β)), 3.72−3.69 (m, 2H, GlcNAc
ring H-3,3′(α)), 3.60−3.47 (m, 2H, GlcNAc ring H-4,4′(α), H-
3,3′,4,4′(β)), 3.28−3.23 (m, 1H, Hε (L-Lys)), 3.19−3.14 (m, 1H, Hε
(L-Lys)), 2.99 (t, J = 7.4 Hz, 2H, 2Hε′ (L-Lys)), 2.40−2.34 (m, 4H,
2Hγ, 2Hγ′ (D-Glu)), 2.24−2.18 (m, 2H, Hβ, Hβ′ (D-Glu)), 2.05−1.95
(m, 8H, Hβ, Hβ′ (D-Glu), -COCH3 (×2)), 1.88−1.68 (m, 6H, 2Hβ,
2Hβ′, 2Hδ′ (L-Lys)), 1.55−1.50 (m, 2H, 2Hδ (L-Lys)), 1.46−1.35 (m,
16H, 2Hγ, 2Hγ′ (L-Lys), -CH3, -CH3′ (L-Ala), -COCH(CH3)O-
(×2)); 13C{1H} NMR (151 MHz, deuterium oxide) δ 177.2, 176.9,
176.5, 176.28, 176.20, 175.4, 175.2, 174.7, 174.4, 174.3, 95.4, 91.4,
83.0, 82.9, 80.1, 80.0, 78.5, 78.2, 76.2, 72.0, 69.48, 69.42, 69.27, 69.21,
61.2, 61.0, 59.8, 56.6, 54.5, 54.2, 53.4, 52.7, 50.2, 50.0, 39.6, 39.4,
31.98, 31.90, 31.0, 30.6, 28.3, 27.3, 27.1, 26.7, 22.8, 22.7, 22.6, 22.5,
20.9, 19.1, 17.3, 17.2; HRMS (ESI) m/z [M + H]+ calcd for
C50H85N10O25 1225.5687, found 1225.5670.
18a: 1H NMR (600 MHz, deuterium oxide) δ 7.44−7.37 (m, 10H,
aromatic(OBn)), 4.91−4.89 (m, 2H, anomeric H-1, anomeric H-1′),
4.73 (d, J = 12.0 Hz, 2H, -OCHHPh (×2)), 4.53 (d, J = 12.0 Hz, 2H,
-OCHHPh (×2)), 4.39−4.34 (m, 2H, Hα, Hα′ (D-Glu)), 4.31−4.17
(m, 7H, Hα, Hα′ (L-Lys), Hα, Hα′ (L-Ala), Hα (D-Ala), -COCH(Me)O-
(×2)), 3.94−3.92 (m, 2H, GlcNAc ring H-2,2′), 3.84−3.75 (m, 6H,
GlcNAc ring H-5,5′,6,6′), 3.72−3.68 (m, 2H, GlcNAc ring H-3,3′),
3.59 (t, J = 9.3 Hz, 2H, GlcNAc ring H-4,4′), 3.21−3.10 (m, 2H, 2Hε
(L-Lys)), 2.97 (t, J = 7.7 Hz, 2H, 2Hε′ (L-Lys)), 2.38−2.29 (m, 4H,
16b. In a round-bottom flask, 17b (13 mg, 0.009 mmol, 1.0 equiv)
was dissolved in 2 mL of water and 100 μL of acetic acid was added
followed by 10 mg of Pd/C (20 wt % loading). The flask was then
purged with hydrogen and allowed to stir for 24 h under hydrogen
(balloon). Removal of benzyl protecting groups was confirmed by
LC-MS. Next, the Pd/C catalyst was filtered by being passed through
a 0.22 μm filter, and the filtrate was lyophilized to give 16b (10 mg,
87% yield) as a white solid [as a mixture of anomeric α and β isomers
1
(1:0.23)] (protium counts for the major isomer are reported): H
E
J. Org. Chem. XXXX, XXX, XXX−XXX