Paper
Organic & Biomolecular Chemistry
4.09–4.19 (2 H, m, H1′,6), 4.29–4.40 (2 H, m, H1′,6), 4.95 (1 H, H, dd, J1b′,2′ 2.3, J1b′,1a′ 11.9 Hz, H1b′), 4.73 (1 H, d, J1,2 3.2 Hz,
dd, J1,2 3.6, J2,3 10.1 Hz, H2), 5.09–5.21 (3 H, m, H1,2′,4), H1), 5.20–5.27 (1 H, m, H2′), 5.30–5.41 (2 H, m, HCvCH); 13C
5.27–5.37 (2 H, m, HCvCH), 5.50 (1 H, t, J2,3 = J3,4 9.7 Hz, H3); {1H} NMR (d4-methanol, 150 MHz) δ 14.52, 14.54 (2 × CH3),
13C{1H} NMR (CDCl3, 100 MHz) 14.2 (2 × CH2CH3), 22.8, 24.96, 23.8, 26.05, 26.07, 28.2, 30.2, 30.3, 30.38, 30.41, 30.51, 30.53,
25.01, 27.27, 27.32, 29.18, 29.21, 29.23, 29.3, 29.4, 29.5, 29.6, 30.67, 30.71, 30.8, 30.9, 32.1, 33.1, 35.0, 35.2 (C6, alkyl–CH2),
29.76, 29.78, 29.80, 29.9, 32.0, 32.02, 34.1, 34.3 (alkyl–CH2), 63.8, 67.0, 71.5, 72.2, 73.4, 74.6, 74.9 (C2,3,4,5,1′,2′,3′), 100.4
59.4, 59.50, 59.51 (4 C, OCH3), 61.7, 62.1, 67.0, 67.4, 68.4, 69.3, (C1), 130.8, 130.9 (2 C, CvC), 174.5, 174.8 (CvO), 196.8
69.38, 69.43, 69.5, 69.8, 70.5, 70.7, 96.2 (C1), 129.8, 130.1 (2 C, (OvC–S); HRMS (ESI+) calcd for C45H82O10SNa+ (M + Na)
CvC), 169.3, 169.6, 170.0 (4 C, MeOCH2CvO), 173.0, 173.3 837.5526. Found 837.5513.
(sn1-CO2, sn2-CO2); HRMS (ESI+) calcd for C55H96O18Na+ (M +
Na) 1067.6494. Found 1067.6518.
(2′S)-1′-O-Oleoyl-2′-O-palmitoyl-glyceryl 6-deoxy-6-sulfonato-
α-D-glucopyranoside, potassium salt (5)
(2′S)-1′-O-Oleoyl-2′-O-palmitoyl-glyceryl α-D-glucopyranoside (14)
H2O2 (9.8 M, 0.05 mL, 0.2 mmol) was added to a suspension
A solution of t-butylamine (0.154 mL, 1.48 mmol) and 12 of 16 (0.02 g, 0.025 mmol) in potassium phosphate buffer
(0.20 g, 0.082 mmol) in CHCl3 (0.32 mL) and MeOH (0.80 mL) (pH 7, 100 mM, 0.1 mL) and CHCl3/MeOH (1 : 1 1 mL) and the
was stirred at 0 °C for 10 min and then at 10 °C for 3 h at resulting mixture was stirred at 50 °C for 1 h. Aqueous 1 M
which time tlc indicated that the starting material was comple- Na2S2O5 (1 mL) was added, the mixture was stirred briefly, and
tely consumed. The solvent was evaporated under high then extracted with CHCl3 (5 × 5 mL) and the organic layer was
vacuum without heating. Flash chromatography of the residue dried (MgSO4), filtered and evaporated. The crude residue,
(CH2Cl2 to 5 : 95 MeOH/CH2Cl2) afforded 14 as a white syrup comprised of a mixture of the target SQDG and 4-O-acetyl-
(0.060 g, 98%). [α]D20 +59.4° (c 0.865, EtOAc); 1H NMR (d4- SQDG, was treated with hydrazine (0.04 mL, 0.04 mM) in
methanol, 400 MHz) δ 0.88–0.93 (2 × 3 H, m, CH2CH3), EtOH/H2O (17 : 3, 4.7 mL) at 40 °C for 3 h until tlc indicated
1.26–1.40 (46 H, m, alkyl–CH2), 1.56–1.66 (4 H, m, β-CH2), there was only one compound. The solvent was evaporated and
2.00–2.07 (4 H, m, H2CHCvCHCH2), 2.29–2.36 (2 × 2 H, m, flash chromatography of the residue (EtOAc to 37 : 6 : 3 EtOAc/
α-CH2), 3.27–3.35 (1 H, m, H4), 3.39 (1 H, dd, J1,2 3.5, J2,3 9.7 MeOH/H2O) afforded 5 as a white gum (0.015 g, 71%). [α]D20
Hz, H2), 3.55–3.71 (4 H, m, H3,5,6a,3′), 3.76–3.82 (1 H, m, +36.2° (c 0.29, MeOH); 1H NMR (d4-methanol, 400 MHz) δ
H6b), 3.87 (1 H, dd, J3′,3′ 10.7, J2′,3′ 5.4 Hz, H3′), 4.20 (1 H, dd, 0.88–0.96 (2 × 3 H, m, CH2CH3), 1.22–1.43 (46 H, m, alkyl),
J1′,2′ 6.5, J1′,1′ 12.0 Hz, H1′), 4.48 (1 H, dd, J1′,2′ 2.6, J1′,1′ 12.0 Hz, 1.56–1.67 (4 H, m, β-CH2), 2.02–2.08 (4 H, m,
H1′), 4.80 (1 H, d, J1,2 3.5 Hz, H1), 5.23–5.28 (1 H, m, H2′), H2CHCvCHCH2), 2.31–2.40 (2 × 2 H, m, α-CH2), 2.90–2.98 (1
5.33–5.37 (2 H, m, HCvCH); 13C{1H} NMR (d4-methanol, H, m, H6a), 3.11 (1 H, t, J3,4 = J4,5 8.9 Hz, H4), 3.34–3.39 (1 H,
150 MHz) δ 14.4, 14.5 (2 × CH3), 23.8, 26.0, 28.2, 30.2, 30.3, m, H6b), 3.42 (1 H, dd, J1,2 3.3, J2,3 9.8 Hz, H2), 3.56–3.73 (3 H,
30.37, 30.38, 30.48, 30.50, 30.6, 30.7, 30.80, 30.84, 30.9, 33.09, m, H3,5,3′), 4.01–4.16 (2 H, m, H4,3′), 4.19 (1 H, dd, J1a′,2′ 6.5,
33.10, 35.0, 35.2 (alkyl–CH2), 62.6, 63.8, 67.1, 71.58, 71.62, J1a′,1b′ 12.1 Hz, H1a′), 4.52 (1 H, dd, J1b′,2′ 2.2, J1b′,1a′ 11.9 Hz,
73.5, 73.9, 74.9, 73.5 (C2,3,4,5,6,1′,2′,3′), 100.7 (C1), 130.8, H1b′), 4.78 (1 H, d, J1,2 3.5 Hz, H1), 5.30–5.34 (1 H, m, H2′),
130.9 (2 C, CvC), 174.6, 174.9 (CvO); HRMS (ESI+) calcd for 5.34–5.39 (2 H, m, HCvCH); 13C{1H} NMR (d4-methanol,
C43H82O10Na+ (M + Na) 781.5805. Found 781.5819.
150 MHz) δ 14.5 (2 × CH3), 23.8, 26.0, 28.2, 30.1, 30.16, 30.19,
30.3, 30.36, 30.38, 30.47, 30.50, 30.6, 30.7, 30.8, 33.1, 35.0, 35.2
(alkyl–CH2), 54.3 (C6), 64.3, 67.1, 69.9 (3 C, C1′,2′,3′), 71.7,
73.5, 74.9, 75.0 (C2,3,4,5), 100.0 (C1), 130.8, 130.9 (2 C, CvC),
(2′S)-1′-O-Oleoyl-2′-O-palmitoyl-glyceryl 6-S-acetyl-6-deoxy-
6-thio-α-D-glucopyranoside (16)
A solution of PPh3 (0.048 g, 0.186 mmol) and diethyl azodicar- 175.0, 175.1 (CvO); HRMS (ESI−) calcd for C43H79O12S−
boxylate (0.029 mL, 0.186 mmol) in THF (10 mL) was prepared (M − H) 819.5298. Found 819.5152.
and held at 0 °C under nitrogen for 30 min. This solution was
Sodium methyl 6-deoxy-6-sulfonato-α-D-glucopyranoside (19)
then transferred by cannula into a solution of thioacetic acid
(0.0039 mL, 0.056 mmol) and 14 (0.040 g, 0.053 mmol) in THF A solution of 18 26 (3.04 g, 10.0 mmol) and Na2SO3 (5.06 g,
(5 mL) at 0 °C under nitrogen. The resultant reaction mixture 40.2 mmol) in H2O (90 mL) was stirred at 80 °C for 4 h, then
was stirred at 4 °C under nitrogen overnight. The solvents were evaporated to dryness under reduced pressure. MeOH (75 mL)
evaporated and flash chromatography of the residue (CH2Cl2 was added to the residue and the mixture was stirred at rt for
to 3 : 97 MeOH/CH2Cl2) afforded 16 as a white oil (0.027 g, 16 h. The filtrate was evaporated to dryness under reduced
73%). [α]2D0 +62.0° (c 0.47, MeOH); 1H NMR (d4-methanol, pressure and the residue purified by flash chromatography
400 MHz) δ 0.87–0.94 (2 × 3 H, m, CH2CH3), 1.25–1.42 (46 H, (EtOAc/MeOH/H2O, 9 : 2 : 1 → 3 : 2 : 1) to afford 19 as a colour-
m, alkyl), 1.57–1.66 (4 H, m, β-CH2), 1.99–2.08 (4 H, m, less solid (2.72 g, 97%). [α]D +91.3° (c 0.855, MeOH; lit.33
H2CHCvCHCH2), 2.29–2.37 (2 × 2 H, m, α-CH2), 2.33 (3H, s, +82.1); 1H NMR (400 MHz, D2O) δ 3.08 (1 H, dd, J6a,6b 14.7,
SAc), 2.93 (1 H, dd, J5,6a 8.6, J6a,6b 13.6 Hz, H6a), 3.14 (1 H, t, J5,6a 9.8 Hz, H6a), 3.26 (1 H, t, J3,4 = J4,5 9.4 Hz, H4), 3.40 (1 H,
J3,4 = J4,5 9.2 Hz, H4), 3.39 (1 H, dd, J1,2 3.2, J2,3 9.5 Hz, H2), d, J6a,6b 14.7 Hz, H6b), 3.47 (3 H, s, Me), 3.59 (1 H, dd, J2,3 9.8,
3.50–3.65 (4 H, m, H3,5,6b,3′), 3.86 (1 H, dd, J3′,3′ 10.5, J2′,3′ 5.3 J1,2 3.8 Hz, H2), 3.68 (1 H, t, J2,3 = J3,4 9.4 Hz, H3), 4.04 (1 H, t,
Hz, H3′), 4.22 (1 H, dd, J1a′,2′ 6.6, J1a′,1b′ 12.0 Hz, H1a′), 4.45 (1 J4,5 = J5,6a 9.5 Hz, H5); 13C{1H} NMR (101 MHz, D2O) δ 52.0 (1
Org. Biomol. Chem.
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