Y. Tokairin et al.
and evaporated in vacuo. The residue was purifed by col-
umn chromatography (CHCl3:MeOH = 99:1) to give the
compound 17 (1.42 g, 1.95 mmol, 98%, dr=10:1) as a red
oil. [α]2D9 − 623.5 (c 1.30, CHCl3). IR (flm) νmax cm−1:
3583, 2964, 2922, 2876, 1733, 1671, 1638, 1533, 1461,
compound 20 (1.78 g, 4.18 mmol, 74%) as a colorless oil.
[α]2D5 +6.32 (c=0.38, CHCl3). IR (flm) νmax cm−1: 3356,
3033, 2966, 1732, 1520, 1455, 1386, 1335, 1193, 1068, 990,
738, 697, 665 cm−1. 1H NMR (600 MHz, CDCl3): δ=0.99
(3H, d, J = 7.2 Hz), 2.20 (1H, dd, J = 13.0, 7.5 Hz), 2.41
(1H, dd, J = 13.0, 4.5 Hz), 2.53–2.58 (1H, m), 4.42 (1H,
dd, J=9.0, 5.4 Hz), 4.55 (2H, d, J=6.0 Hz), 5.10 (2H, s),
5.16 (1H, d, J = 19.8 Hz), 5.18 (1H, d, J = 19.2 Hz), 5.23
(1H, dd, J=10.2, 1.2 Hz), 5.29 (1H, dd, J=16.8, 1.2 Hz),
5.51 (1H, br), 5.75 (1H, dddd, J=16.8, 11.4, 6.6, 6.6 Hz),
7.34–7.36 (10H, m) ppm. 13C NMR (150 MHz, CDCl3):
δ=16.8, 33.5, 37.4, 58.2, 65.4, 67.3, 67.4, 118.6, 128.25,
128.33, 128.6, 128.65, 128.74, 132.1, 135.2, 136.2, 156.2,
171.4, 171.9 ppm. HRMS-ESI: m/z [M + H]+ calcd for
C24H27NNaO6: 448.1736; found: 448.1759.
1396, 1320, 1249, 1167, 1069, 990, 828, 753, 665 cm−1
.
1H NMR (600 MHz, CDCl3): δ=1.97 (3H, d, J=6.6 Hz),
1.99 (overlapped, 1H, dd, J=15.6, 4.8 Hz), 2.13–2.21 (2H,
m), 2.31 (1H, dd, J=16.2, 9.6 Hz), 2.60 (1H, ddd, J=19.8,
13.2, 9.0 Hz), 2.72–2.76 (1H, m), 3.19 (1H, d, J=13.2 Hz),
3.37 (overlapped, 1H, dd, J = 11.4, 6.0 Hz), 3.33–3.44
(overlapped, 1H, m), 3.53 (1H, dd, J=10.2, 6.6 Hz), 3.91
(1H, d, J = 3.6 Hz), 4.30 (1H, d, J = 12.0 Hz), 4.38 (1H,
dd, J=12.6, 5.4 Hz), 4.43 (1H, dd, J=13.2, 5.4 Hz), 5.18
(1H, dd, J=10.8, 1.8 Hz), 5.22 (1H, dd, J=17.4, 1.8 Hz),
5.79 (1H, dddd, J = 16.2, 10.8, 6.0, 6.0 Hz), 6.57 (1H, d,
J=3.0 Hz), 6.92 (1H, d, J=7.2 Hz), 7.09 (1H, dd, J=9.6,
2.4 Hz), 7.28 (1H, d, J=6.6 Hz), 7.32 (1H, d, J=8.4 Hz),
7.47 (1H, dt, J=6.6, 1.2 Hz), 7.52 (1H, t, J=7.2 Hz), 7.56
(1H, t, J=7.2 Hz), 7.67 (1H, dd, J=7.2, 2.4 Hz), 7.67 (1H,
dd, J=7.2, 2.4 Hz), 8.13 (1H, d, J =9.0 Hz), 8.96 (1H, d,
J = 1.8 Hz) ppm. 13C NMR (150 MHz, CDCl3): δ = 15.8,
23.0, 30.8, 34.9, 38.1, 58.2, 63.2, 64.9, 71.4, 73.9, 118.0,
123.8, 125.6, 127.0, 127.2, 127.6, 129.2, 129.3, 129.7,
130.1, 131.0, 132.0, 132.3, 132.4, 132.8, 133.18, 133.25,
133.6, 135.1, 140.6, 171.1, 177.1, 179.9 ppm. HRMS-ESI:
m/z [M+H]+ calcd for C34H33Cl3N3NiO5: 726.0839; found:
726.0830.
(2S,3S)‑Z‑3‑MeGlu‑OBn (21)
To a solution of 20 (515 mg, 1.20 mmol) in CH2Cl2 (5 ml)
was added Pd(PPh3)4 (70 mg, 0.605 μmol) and PhSiH3
(0.295 ml, 2.40 mmol) at room temperature, and the reac-
tion mixture was stirred for 2 h. The mixture was evaporated
in vacuo. The residue was purifed by column chromatog-
raphy (Hexane:AcOEt=3:1) to give the title compound 21
(317 mg, 0.822 mmol, 69%) as a colorless oil. [α]2D5 −4.4
(c=0.5, CHCl3). IR (flm) νmax cm−1: 3330, 3067, 3034,
2966, 1715, 1524, 1455, 1410, 1337, 1213, 1070, 739, 698,
1
665, 455. H NMR (600 MHz, CDCl3): δ = 0.99 (3H, d,
J=6.6 Hz), 2.20 (1H, dd, J=16.8, 9.0 Hz), 2.42 (1H, dd,
J=15.6, 4.8 Hz), 2.50-2.53 (1H, m), 4.42 (1H, dd, J=8.4,
4.8 Hz), 5.10 (2H, s), 5.15 (1H, d, J=12.6 Hz), 5.19 (1H,
d, J = 11.4 Hz), 5.51 (1H, d, J= 9.0 Hz), 7.33–7.35 (10H,
m) ppm. 13C NMR (150 MHz, CDCl3): δ = 16.7, 33.5,
37.2, 58.1, 67.4, 67.6, 128.3, 128.4, 128.6, 128.70, 128.74,
128.8, 135.1, 136.2, 156.3, 171.4, 177.2 ppm. HRMS-ESI:
m/z [M + Na]+ calcd for C21H23NNaO6: 408.1423; found:
408.1441.
(2S,3S)‑Z‑3‑MeGlu(OAllyl)‑OBn (20)
To a solution of 17 (4.19 g, 5.76 mmol) in THF (20 ml) was
added 6 M HCl (5 ml) at room temperature, and the reac-
tion mixture was stirred for 30 min. The mixture was diluted
with H2O and aqueous layer washed twice with AcOEt. The
aqueous layer was lyophilized in vacuo. To a solution of
the residue in sat. NaHCO3 aq. (10 ml) were added EDTA
(3.37 g, 11.5 mmol) and Z-OSu (1.44 g, 5.76 mmol) in
dioxane solution at room temperature, and the mixture was
stirred for 2 h. H2O and Et2O were added to the solution
and the aqueous phase was washed twice with Et2O. To the
aqueous phase was added with 2 M HCl and extracted twice
with AcOEt. The combined organic layer was washed with
brine, dried over MgSO4, and evaporated in vacuo to give
the Z-3Me-Gln(OAllyl)-OH (19) (1.90 g). To a solution of
19 in DMF (20 ml) were added BnBr (1.28 ml, 8.50 mmol)
and K2CO3 (1.17 g, 8.50 mmol) at room temperature, and
the reaction mixture was stirred for 1 h. The mixture was
quenched with saturated NH4Cl aq. and aqueous layer was
extracted three times with Hexane/AcOEt (4:1). The organic
layer was washed with H2O and brine, dried over MgSO4,
and evaporated in vacuo. The residue was purifed by col-
umn chromatography (Hexane:AcOEt=6:1) to give the title
(2S,3S)‑Z‑3‑MeGln(Xan)‑OBn (22)
To a solution of 21 (317 mg, 0.822 mmol) in MeCN (5 ml)
was added WSC hydrochloride salt (315 mg, 1.64 mmol),
HOBt monohydrate (251 mg, 1.64 mmol), 9-aminoxanthene
(323 mg, 1.64 mol), and Et3N (0.464 ml, 3.28 mmol) at
r.t., and the reaction mixture was stirred for overnight. The
mixture was quenched with H2O and aqueous layer was
extracted twice with CH2Cl2. The organic layer was washed
with brine, dried over MgSO4, and evaporated in vacuo. The
resulting solid was washed with AcOEt to give the title com-
pound 22 (370 mg, 0.655 mmol, 80%) as a white solid. [α]D25
− 3.8 (c = 1.0, DMF). IR (KBr) νmax cm−1: 3290, 3057,
3039, 2961, 1726, 1685, 1525, 1488, 1460, 1378, 1315,
1266, 1215, 1165, 1097, 1043, 973, 907, 755, 701 cm−1. 1H
1 3