2), 3.76 (dd, J = 11.9, 10.9 Hz, 1H, H-3), 3.68 (ddd, J = 9.5, 4.8,
2.6 Hz, 1H, H-5), 2.31 (s, 3H, COCH3), 2.08 (s, 3H, COCH3),
2.00 (s, 3H, COCH3), 1.88 (s, 3H, COCH3). 13C NMR (101 MHz,
CDCl3) δ 196.2, 170.8, 170.0, 169.4, 137.1, 128.5, 128.1, 128.0,
101.1, 74.7, 70.4, 67.2, 62.5, 54.1, 48.1, 30.8, 23.3, 20.9, 20.7.
170.8, 170.7, 170.0, 138.5, 129.2, 129.0, 128.3, 128.3, 100.7,
74.0, 72.5, 71.2, 69.3, 62.8, 59.7, 34.1, 20.6, 20.6, 20.6.
Benzyl 2-thioacetamido-3-S-acetyl-4,6-di-O-acetyl-2-deoxy-3-
thio-β-D-glucopyranoside (31)
Benzyl 2-acetamido-3-azido-4,6-di-O-acetyl-2,3-dideoxy-β-D-
glucopyranoside (32)
Compound 30 (100 mg, 0.213 mmol) was was thionated
according to the general procedure. The product was obtained as
a white solid (54.1 mg, 53%). 1H NMR (500 MHz, Acetone-d6) δ
9.06 (d, J = 9.7 Hz, 1H, NH), 7.38 – 7.24 (m, 5H, Ph), 5.20 –
5.13 (m, 1H, H-2), 5.07 (dd, J = 10.8, 9.6 Hz, 1H, H-4), 4.95 –
4.90 (m, 1H, H-1), 4.87 (d, J = 12.3 Hz, 1H, CH2Ph), 4.66 (d, J =
12.4 Hz, 1H, CH2Ph), 4.27 (dd, J = 12.2, 5.0 Hz, 1H, H-6a), 4.11
(dd, J = 12.2, 2.6 Hz, 1H, H-6b), 4.00 – 3.91 (m, 1H, H-3), 3.88
(ddd, J = 9.6, 5.0, 2.6 Hz, 1H, H-5), 2.42 (s, 3H, CSCH3), 2.29 (s,
3H, COCH3), 2.03 (s, 3H, COCH3), 1.97 (s, 3H, COCH3).13C
NMR (126 MHz, Acetone-d6) δ 203.1, 194.5, 170.7, 169.9,
138.6, 129.0, 128.3, 128.2, 75.3, 70.9, 68.9, 63.2, 58.4, 49.2,
34.0, 30.6, 20.7, 20.6.
Compound 27 (87.6 mg, 0.206 mmol) was deprotected according
to the general procedure and purified by silica column
chromatography (solvent gradient: 100% DCM to 20:1
DCM/acetone), yielding the product as a white solid (83.3 mg,
96%). 1H NMR (400 MHz, CDCl3) δ 7.52 – 7.14 (m, 5H, Ph),
5.83 (d, J = 7.3 Hz, 1H, NH), 5.13 (d, J = 8.2 Hz, 1H, H-1), 5.03
– 4.76 (m, 2H, H-4 and CH2Ph), 4.57 (d, J = 11.7 Hz, 1H,
CH2Ph), 4.48 (dd, J = 11.0, 9.7 Hz, 1H, H-3), 4.27 (dd, J = 12.3,
4.9 Hz, 1H, H-6a), 4.11 (dd, J = 12.3, 2.5 Hz, 1H, H-6b), 3.72
(ddd, J = 9.9, 4.9, 2.5 Hz, 1H, H-5), 3.08 (ddd, J = 11.0, 8.2, 7.3
Hz, 1H, H-2), 2.11 (s, 3H, COCH3), 2.10 (s, 3H, COCH3), 1.96
(s, 3H, COCH3). 13C NMR (101 MHz, CDCl3) δ 171.1, 170.9,
169.7, 137.0, 128.7, 128.3, 128.3, 98.5, 72.6, 71.6, 69.7, 62.3,
61.8, 57.6, 23.6, 20.9, 20.8.
Benzyl 2-acetamido-2-deoxy-β-D-glucopyranoside (20)
Compound 19 (7.85 g, 22.1 mmol) was deprotected according to
the general Zemplén deacetylation procedure, giving a white
solid (5.50 g, 96%). 1H NMR (400 MHz, MeOD) δ 7.45 – 7.21
(m, 5H, Ph), 4.91 (d, J = 12.2 Hz, 1H, CH2Ph), 4.64 (d, J = 12.1
Hz, 1H, CH2Ph), 4.50 (d, J = 8.4 Hz, 1H, H-1), 3.94 (dd, J =
11.9, 2.3 Hz, 1H, H-6a), 3.82 – 3.65 (m, 2H, H-2 and H-6b), 3.47
(dd, J = 10.3, 8.5 Hz, 1H, H-3), 3.37 (t, J = 6.0 Hz, 1H, H-4),
3.30 (m, 1H, H-5), 1.98 (s, 3H, COCH3).13C NMR (101 MHz,
MeOD) δ 173.7, 139.2, 129.3, 128.8, 128.6, 101.8, 78.1, 76.0,
72.2, 71.5, 62.9, 57.4, 23.0.
Benzyl 2-methylsulfonamido-3-S-acetyl-4,6-di-O-acetyl-2-
deoxy-3-thio-β-D-glucopyranoside (33)
Compound 28 (88.0 mg, 0.178 mmol) was deprotected according
to the general procedure. It was purified by silica column
chromatography (solvent gradient: 100% DCM to 10:1
DCM/EtOAc), giving the product as a white solid (56.1 mg,
64%).1H NMR (400 MHz, Acetone-d6) δ 7.55 – 7.25 (m, 5H,
Ph), 6.20 (d, J = 8.8 Hz, 1H, NH), 5.09 (dd, J = 10.5, 9.7 Hz, 1H,
H-4), 4.95 (d, J = 11.4 Hz, 1H, CH2Ph), 4.78 (d, J = 7.6 Hz, 1H,
H-1), 4.73 (d, J = 11.4 Hz, 1H, CH2Ph), 4.26 (dd, J = 12.1, 5.4
Hz, 1H, H-6a), 4.11 (dd, J = 12.1, 2.6 Hz, 1H, H-6b), 3.85 (ddd, J
= 9.7, 5.4, 2.6 Hz, 1H, H-5), 3.72 – 3.56 (m, 2H, H-2 and H-3),
2.82 (s, 3H, CSO2CH3), 2.32 (s, 3H, COCH3), 2.04 (s, 3H,
COCH3), 2.00 (s, 3H, COCH3). 13C NMR (101 MHz, Acetone-d6)
δ 195.0, 170.8, 170.0, 138.0, 129.5, 129.3, 128.9, 103.1, 103.0,
75.3, 71.9, 68.8, 63.4, 58.4, 58.3, 50.7, 50.6, 43.1, 30.8, 20.8,
20.7. ESI-MS calc for C20H31N2O9S2 [M+NH4]+: 507.15; found
507.15.
Benzyl 2-thioacetamido-2-deoxy-β-D-glucopyranoside (34)
Compound 29 (10.5 mg, 0.024 mmol) was deprotected according
to the general Zemplén deacetylation procedure, giving a white
solid (7.3 mg, 98%). 1H NMR (400 MHz, D2O) δ 7.45 – 7.24 (m,
5H, Ph), 4.82 (d, J = 12.3 Hz, 1H, CH2Ph), 4.65 – 4.55 (m, 3H,
H-1, H-2 and CH2Ph), 3.89 (dd, J = 12.4, 2.1 Hz, 1H, H-6a), 3.72
(dd, J = 12.4, 5.5 Hz, 1H, H-6b), 3.52 (t, J = 9.1 Hz, 1H, H-3),
3.45 (t, J = 9.0 Hz, 1H, H-4), 3.42 – 3.37 (m, 1H, H-5), 2.39 (s,
3H, CSCH3). 13C NMR (101 MHz, D2O) δ 204.3, 136.7, 128.7,
128.5, 128.4, 99.5, 76.0, 74.1, 71.4, 69.7, 61.1, 60.7, 32.9.
DART-MS calc for C15H22NO5S [M+H]+: 328.1; found 328.0.
General procedure for thioacetamido synthesis.
Benzyl 2-acetamido-2-deoxy-3-thio-β-D-glucopyranoside (35)
The starting acetamido sugar was suspended in dry toluene (0.2
M) under Ar(g). It was reacted with Lawesson’s reagent (0.6 eq)
at 80 ℃ for 4 h. Evaporation of solvent give a white foam which
was purified by silica chromatography (20:1 DCM/EtOAc).
Compound 30 (340.0 mg, 0.750 mmol) was deprotected
according to the general Zemplén deacetylation procedure. The
reaction was conducted using Ar(g) purged MeOH to prevent
disulfide formation. The product was obtained as a white solid
(242.1 mg, 99%). 1H NMR (400 MHz, MeOD) δ 7.39 – 7.22 (m,
5H, Ph), 4.87 (d, J = 12.1 Hz, 1H, CH2Ph), 4.61 (d, J = 12.2 Hz,
1H, CH2Ph), 4.46 (d, J = 8.2 Hz, 1H, H-1), 3.90 (dd, J = 11.9, 1.9
Hz, 1H, H-6a), 3.80 – 3.65 (m, 2H, H-2 and H-6b), 3.32 – 3.28 (m
obscured by MeOD, H-4 and H-5), 2.89 (dt, J = 10.4, 4.7 Hz, 1H,
H-3), 1.95 (s, 3H, COCH3).13C NMR (101 MHz, MeOD) δ 173.3,
139.1, 129.3, 128.8, 128.7, 102.6, 80.6, 73.1, 71.4, 63.0, 57.3,
48.6, 22.8. ESI-MS calc for C15H22NO5S [M+H]+: 328.1; found
328.1.
Benzyl 2-thioacetamido-3,4,6-tri-O-acetyl-2-deoxy-β-D-
glucopyranoside (29)
Compound 19 (100 mg, 0.229 mmol) was thionated according to
the general procedure. The product was obtained as viscous oil
(52.9 mg, 51%). 1H NMR (400 MHz, Acetone-d6) δ 9.03 (d, J =
9.3 Hz, 1H, NH), 7.19 – 7.00 (m, 5H, Ph), 5.09 (t, J = 9.8 Hz,
1H, H-3), 5.00 – 4.85 (m, 2H, H-2, H-4), 4.76 (d, J = 8.3 Hz, 1H,
H-1), 4.68 (d, J = 12.2 Hz, 1H, CH2Ph), 4.46 (d, J = 12.2 Hz, 1H,
CH2Ph), 4.10 (dd, J = 12.3, 4.9 Hz, 1H, H-6a), 3.96 (dd, J = 12.3,
2.5 Hz, 1H, H-6b), 3.68 (ddd, J = 10.0, 4.9, 2.5 Hz, 1H, H-5),
2.22 (s, 3H, CSCH3), 1.84 (s, 3H, COCH3), 1.80 (s, 3H, COCH3),
1.72 (s, 3H, COCH3).13C NMR (101 MHz, Acetone-d6) δ 203.2,
Benzyl 2-thioacetamido-2-deoxy-3-thio-β-D-glucopyranoside
(36)