3 equiv.) were used, to give, after flash chromatography on silica
gel (CH2Cl2–MeOH 9.5 : 0.5 to 9 : 1), 47 (176 mg, 74%).
3H, H1carb), 5.43 (m, 1H, H3A), 5.55 (m, 1H, H3), 5.62–5.72 (m,
6H, 3 ¥ H2carb, 3 ¥ H3carb), 5.72–5.84 (m, 4H, H3, 3 ¥ H4carb), 7.26
(m, 2H, CHAr), 7.40 (t, 2H, J 6.9 Hz, CHAr), 7.60 (m, 2H, 2HAr),
7.84 (d, 2H, J 7.6 Hz, CHAr), 8.19, 8.32 and 8,34 (3 s, 3H, Csp2H),
9.07 (d, 1H, J 8.4 Hz, NHA), 9.40 (m, 2H, 2 ¥ NH¢), 9.59 (d, 1H,
J 8.5 Hz, NH), 9.72 (d, 1H, J 8.0 Hz, NH), 9.73 (m, 1H, NH¢);
dC (100.1 MHz; Pyridine-d5) 20.9, 21.0 and 21.2 (12C, CH3CO),
28.4 (C(CH3)3), 36.2 and 36.3 (2C, NHCH2), 48.0 (CH Fmoc), 50.1
(3C, OCH2CH2), 51.5, 51.6 and 53.6 (3C, C3), 63.1 (3C, C6carb), 66.8
(3C, C4carb), 67.1 and 67.2 (4C, 3 ¥ OCH2CH2, CH2 Fmoc), 69.9
(3C, C5carb), 70.29, 70.34 and 70.4 (6C, 3 ¥ C2carb, 3 ¥ C3carb), 81.1
(C(CH3)3), 98.4 (3C, C1carb), 120.9 (CHAr), 126.1 and 126.2 (3C,
Csp2H), 128.0 and 128.5 (CHAr), 142.1 (CAr), 145.0, 146.4, 146.5
(EtO)3PCuI. Alkyne 23 (75 mg, 0.125 mmol), sugar azide
40 (118 mg, 0.250 mmol), (EtO)3PCuI (9 mg, 0.025 mmol) and
diisopropyl ethyl amine (0.065 ml, 0.375 mmol) were dissolved
in DMF (2 ml) and exposed to 15 W microwave irradiation at
80 ◦C for 30 min. After cooling to room temperature, the solution
was concentrated in vacuo, and the residue was purified by flash
chromatography on silica gel (AcOEt) to yield the glycoconjugate
46 (62 mg, 35%) as a white solid. Mp 116–119 ◦C; [a]D24 +14.2 (c 0.58
in CHCl3); Rf 0.30 (CH2Cl2–MeOH, 98 : 2); vmax (KBr)/cm-1 3304
2
=
=
and 3295 (NH), 3082 (Csp -H), 1748 (C O, ester), 1659 (C O,
Fmoc, amide); dH (400 MHz; CDCl3) 1.41 (s, 9H, C(CH3)3), 1.97,
1.99, 2.02, 2.03, 2.07, 2.08 and 2.09 (7 s, 24H, CH3CO), 2.62 (dd,
1H, J 3.7, 14.5 Hz, H2A), 2.72 (m, 1H, H2¢A), 2.74 (dd, 1H, J 5.4,
16.6 Hz, H2B), 2.84 (dd, 1H, J 6.1, 16.6 Hz, H2¢B), 3.59 (m, 1H,
H5carb), 3.65 (m, 1H, H5carb), 3.76–3.88 (m, 2H, 2 ¥ OCHHCH2),
3.98–4.10 (m, 4H, 2 ¥ OCHHCH2, 2 ¥ H6carb), 4.13 (m, 1H, CH
Fmoc), 4.19 (dd, 2H, J 5.1 12.5 Hz, 2 ¥ H6carb), 4.40 (m, 2H,
CH2 Fmoc), 4.35–4.46 (m, 3H, NHCHH), 4.52–4.56 (m, 4H,
OCH2CH2), 4.64 (dd, 1H, J 6.3, 15.4 Hz, NHCHH), 4.69–4.74
(m, 2H, H3A, H1carb), 4.76 (s, 1H, H1carb), 4.83 (m, 1H, H3B), 5.16
(m, 1H, H2carb), 5.17–5.30 (m, 5H, 2 ¥ H3carb, 2 ¥ H4carb, H2carb), 6.29
(d, 1H, J 8.4 Hz, NHA), 7.28 (t, 2H, J 7.3 Hz, HAr), 7.38 (t, 2H, J
7,2 Hz, HAr), 7.43 (m, 2H, NHB, NH¢), 7.55 (d, 1H, J 7.2 Hz, HAr),
7.56 (d, 1H, J 7.3 Hz, HAr), 7.68 and 7.69 (2 s, 2H, 2 ¥ Csp2H),
7.74 (d, 2H, J 7.5 Hz, HAr), 7.85 (m, 1H, NH¢); dC (100.1 MHz;
CDCl3) 20.6, 20.7 and 20.9 (8C, CH3CO), 28.0 (C(CH3)3), 35.2
and 35.3 (2C, NHCH2), 36.9 (C2B), 38.1 (C2A), 47.1 (CH Fmoc),
49.5 (2C, OCH2CH2), 49.6 (C3B), 51.5 (C3A), 62.2 (2C, C6carb), 65.4
and 65.7 (2C, C4carb), 66.1 and 66.2 (2C, OCH2CH2), 66.9 (CH2
=
and 147.0 (3 ¥ C6, CAr), 155.8 (C O, Fmoc), 170.5, 170.6, 170.7,
170.7, 171.1, 171.2, 171.5 and 173.1 (3 ¥ C1, 3 ¥ C4, CH3CO);
HRMS (ESI) m/z calcd. for C88H113N15O39 [M +H]+: 1002.8733
found: 1002.8732.
Glycoconjugated tetramer (49)
The cycloaddition between alkyne 27 (70 mg, 0.077 mmol) and
sugar azide 40 (129 mg, 0.309 mmol) was carried out as described
for the preparation of 30 excepted for CuSO4 and ascorbic acid
quantities, 0.1 M CuSO4 solution (0.774 ml, 1 equiv.) and 0.1 M
ascorbic acid solution (2.32 ml, 3 equiv.) were used, to give after
flash chromatography on silica gel (CH2Cl2–MeOH 9.5 : 0.5), 49
(157 mg, 80%), as a white solid. Mp 162–164 ◦C; [a]D25 +20.7 (c 0.57
in CHCl3); Rf 0.88 (CH2Cl2–MeOH, 8 : 2); vmax (KBr)/cm-1 3300
2
=
(NH), 3144, 3078 and 3063 (Csp -H), 1748 and 1647 (C O, ester,
Fmoc, amide); dH (500 MHz; Pyridine-d5) 1.42 (s, 9H, C(CH3)3),
1.97, 1.99, 2.00, 2.03, 2.08, 2.08 and 2.10 (7 s, 48H, CH3CO),
2.92 (dd, 1H, J 8.6, 15.6 Hz, H2D), 2.93–3.02 (m, 3H, H2A, H2B,
Fmoc), 68.8, 68.9, 69.0, 69.1 and 69.3 (6C, 2 ¥ C2carb, 2 ¥ C3carb
,
H2C), 3.09 (dd, 1H, J 8.6, 13,9 Hz, H2), 3.13–3.25 (m, 2H, H2¢A
,
2 ¥ C5carb), 81.3 (C(CH3)3), 97.4 and 97.5 (2C, C1carb), 120.0 (CHAr),
H2), 3.31 (dd, 1H, J 5.2, 15,6 Hz, H2¢D), 3.92–4.12 (m, 8H, 4 ¥
H5carb, 4 ¥ OCHHCH2), 4.13–4.37 (m, 6H, 4 ¥ OCHHCH2, CH
Fmoc, CHH Fmoc), 4.36–4.46 (m, 4H, H6carb), 4.48–4.60 (m, 5H,
4 ¥ H6carb, CHH Fmoc), 4.77–4.94 (m, 16H, 8 ¥ NHCHH, 8 ¥
OCH2CHH), 5.12, 5.13 and 5.18 (3 s, 4H, H1carb), 5.41 (m, 1H,
H3A), 5.54 (m, 1H, H3D), 5.67–5.76 (m, 14H, 2 ¥ H3, 4 ¥ H2carb, 4 ¥
H3carb, 4 ¥ H4carb), 7.26 (m, 2H, 2HAr), 7.40 (t, 2H, J 7.5 Hz, HAr);
7,61 (m, 2H, HAr), 7.83 (d, 2H, J 7.5 Hz, HAr), 8.40 (d, 2H, J
5.6 Hz, HAr), 8.08, 8.20, 8.30 and 8.39 (4 s, 4H, Csp2H), 9.04 (d,
1H, J 8.5 Hz, NHA), 9.35–9.49 (m, 3H, NH¢), 9.56 (d, 1H, J 8.4 Hz,
NHD), 9.63 (m, 2H, NHB, NHC), 9.71 (t, 1H, J 5.1 Hz, NH¢); dC
(100.1 MHz; Pyridine-d5) 20.9, 21.1 and 21.2 (16C, CH3CO), 28.4
(C(CH3)3 CO2tBu), 36.2 and 36.3 (4C, NHCH2), 38.8 (C2D), 39.5,
39.6 and 39.9 (3C, C2), 48.1 (CH Fmoc), 50.1 (4C, OCH2CH2),
51.5 (C3D), 51.6 and 51.6 (2C, C3) 53.7 (C3A), 63.1 (4C, C6carb), 66.8
(4C, C4carb), 67.2 (5C, 4 ¥ OCH2CH2, CH2 Fmoc), 69.8, 70.3 and
70.4 (12C, 4 ¥ C2carb, 4 ¥ C3carb, 4 ¥ C5carb), 81.1 (C(CH3)3), 98.4
123.3 and 123.6 (2C, Csp2H), 124.9, 127.0 and 127.7 (CHAr), 141.2,
2
=
and 143.6 (CAr), 144.8 and 145.6 (2C, Csp ), 156.1 (C O, Fmoc),
169.6, 170.2, 170.4, 170.5, 170.6, 170.8, 171.3 and 171.4 (12C, C1,
C4. CH3CO); HRMS (ESI) m/z calcd. for C65H82N10O27 [M +H]+:
718.2748 found: 718.2753.
Glycoconjugated trimer (48)
The cycloaddition between alkyne 26 (38 mg, 0.05 mmol) and
sugar azide 40 (63 mg, 0.151 mmol) was carried out as described
for the preparation of 30, except for CuSO4 and ascorbic acid
quantities, 0.1 M CuSO4 solution (0.5 ml, 1 equiv.) and 0.1 M
ascorbic acid solution (1.51 ml, 3 equiv.) were used, to give, after
flash chromatography on silica gel (CH2Cl2–MeOH 9.5 : 0.5), 48
(70 mg, 70%), as a white solid. Mp 132–135 ◦C; [a]D25 +18.0 (c 0.45
in CHCl3); Rf 0.41 (CH2Cl2–MeOH, 9 : 1); vmax (KBr)/cm-1 3298
2
=
and 3285 (NH), 3130 and 3072 (Csp -H), 1748 (C O, ester), 1693
(C1carb), 124.0, 125.1 (C7), 120.9, 126.1, 128.0 and 128.6 (CHAr),
=
=
(C O, Fmoc), 1643 (C O, amide); dH (500 MHz; Pyridine-d5)
1.42 (s, 9H, C(CH3)3), 1.99, 2.03, 2.08, 2.08 and 2.10 (5 s, 36H,
CH3CO), 2.92 (dd, 1H, J 8.1, 15.8 Hz, H2), 2,95 (m, 1H, H2),
2.97 (m, 1H, H2A), 3.18 (m, 1H, H2¢A), 3.20 (m, 1H, H2), 3.33 (m,
1H, H2), 3.91–4.02 (m, 3H, H5carb), 4.02–4.10 (m, 3H, OCHHCH2),
4.17 (m, 1H, CH Fmoc), 4.20–4.36 (m, 4H, 3 ¥ OCHHCH2, CHH
2
=
142.1, 145.0, 146.4, 146.5 and 146.9 (4 ¥ Csp , CAr), 157.6 (C O,
Fmoc), 170.6, 170.7, 170.8, 171.1, 171.2, 171.5, 171.6, 172.1, 173.1
and 173.3 (4 ¥ C1, 4 ¥ C4, CH3CO); HRMS (ESI) m/z calcd. for
C111H144N20O50 [M +H]+: 1287.47 found: 1287.4717.
Deprotected glycoconjugated monomer (50)
Fmoc), 4.37–4.47 (m, 3H, H6carb), 4.49–4.61 (m, 4H, 3 ¥ H6carb
,
CHH Fmoc), 4.68 (t, 2H, J 5.3 Hz, OCH2CH2), 4.71–4.89 (m,
10H, OCH2CH2, NHCHH, NHCHH), 5.12, 5.14 and 5.17 (3 s,
The fully protected glycoconjugate 46 (100 mg, 0.116 mmol) was
dissolved in a 2 : 1 CH3CN–Et2NH mixture (4.3 ml) at 0 ◦C. The
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The Royal Society of Chemistry 2010
Org. Biomol. Chem., 2010, 8, 2941–2955 | 2953
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