Paper
Organic & Biomolecular Chemistry
3
.36 (6 H, 2 s, OMe BDA), 2.42 (3 H, d, Me MU), 1.38, 1.35
4.2.6 4-Methylumbelliferyl 4-deoxy-4-fluoro-α-L-arabinopyr-
(
6 H, 2 s, Me BDA); δC (100 MHz, CDCl ) 160.9, 159.5, 154.8, anoside (22). 20 (47 mg, 0.1 mmol) was subjected to the same
3
1
52.2 (4 C, C-1 MU, C-3 MU, C-6 MU, C-8 MU), 125.5 (1 C, C-5 procedure as that described for the preparation of 18 using
MU), 115.1 (1 C, C-0 MU), 113.5 (1 C, C-4 MU), 112.9 (1 C, C-7 95% TFA. Flash chromatography afforded 22 (21 mg, 67%).
MU), 104.7 (1 C, C-2 MU), 99.7, 99.5 (2 C, Cquat BDA), 98.6 (1 C, [α]D +1.0 (c 1.02 in CHCl /MeOH 1 : 1); δH (400 MHz, CDCl3/
3
C-1), 83.6 (1 C, d, J4,F 183.1, C-4), 69.9 (1 C, d, J3,F 22.3, C-3), MeOD 1 : 1) 7.60 (1 H, d, J4,5 8.8, H-5 MU), 7.06 (1 H, dd,
6
8.0 (1 C, d, J2,F 9.7, C-2), 64.4 (1 C, d, J5,F 27.2, C-5), 48.1, (2 C,
J
4,5 8.8, J2,4 2.4, H-4 MU), 7.02 (1 H, d, H-2 MU), 6.17 (1 H, d,
J7,Me 1.5, H-7 MU), 4.98 (1 H, d, J1,2 7.3, H-1), 4.79 (1 H, dm,
4,F 48.9, H-4), 4.19 (1 H, ddd, J5ax,5eq 13.3, J5ax,F 12.2, J4,5ax 2.5,
H-5ax), 3.81 (3 H, m, H-2, H-3, H-5eq), 2.42 (3 H, d, Me MU);
.2.4 4-Methylumbelliferyl 4-deoxy-4-fluoro-β-D-xylopyrano- δC (100 MHz, CDCl /MeOD 1 : 1) 162.1, 160.2, 154.6, 153.8
OMe BDA), 18.7 (1 C, Me MU), 17.6, 17.5 (2 C, Me BDA); δ
F
+
+
(376 MHz, CDCl
3
) −190.4; ESI HRMS [M + H] m/z 425.1606
8
26FO , found: 425.1603.
J
calcd for C21
H
4
3
side (18). A mixture of 17 (80 mg, 0.19 mmol) in 95% TFA (4 C, C-1 MU, C-3 MU, C-6 MU, C-8 MU), 125.8 (1 C, C-5 MU),
1 mL) was stirred at rt for 2 h. The reaction mixture was then 114.9 (1 C, C-0 MU), 113.9 (1 C, C-4 MU), 111.9 (1 C, C-7 MU),
co-evaporated with water (3×), toluene (2×) and CH Cl . Flash 103.9 (1 C, C-2 MU), 100.7 (1 C, C-1), 88.7 (1 C, d, J4,F 179.2,
(
2
2
chromatography (CH
3%) as a white foam. M.p. 208 °C (from MeOH); [α]
c 1.42 in CHCl /MeOH 1 : 1); δH (400 MHz, CDCl /MeOD 1 : 1) MeOD 1 : 1) −206.2; ESI HRMS [M + H] m/z 311.0925 calcd
2
Cl
2
/MeOH 9 : 1) afforded 18 (31 mg, C-4), 71.6 (1 C, d, J3,F 18.3, C-3), 70.7 (1 C, d, J2,F 1.3, C-2), 64.3
5
(
D
−62.9 (1 C, d, J5,F 20.3, C-5), 18.1 (1 C, Me MU); δ (376 MHz, CDCl /
F
3
+
+
3
3
7
.64 (1 H, d, J4,5 8.9, H-5 MU), 7.07 (1 H, dd, J2,4 2.4, H-4 MU), for C15
6
H16FO , found: 311.0927.
7
.03 (1 H, d, H-2 MU), 6.20 (1 H, d, J7,Me 1.7, H-7 MU), 5.09 (1 4.2.7 4-Methylumbelliferyl
2,3-O-(2′,3′-dimethoxybutane-
H, d, J1,2 6.9, H-1), 4.50 (1 H, dm, J4,F 49.7, H-4), 4.16 (1 H, 2′,3′-diyl)-4-O-(phenylthio)thionocarbonyl β-D-xylopyranoside
ddd, J5ax,5eq 12.3, J5eq,F 7.5, J4,5eq 5.2, H-5eq), 3.77 (1 H, ddd, J3, (24). Alcohol 5b (0.468 g, 1.1 mmol) was subjected to the
F
16.5, J2,3 = J3,4 8.5, H-3), 3.66 (1 H, ddd, J5ax,F 8.4, J4,5ax 6.5, general procedure for the preparation of thionocarbonate.
H-5ax), 3.60 (1 H, dd, H-2), 2.45 (3 H, d, Me MU); δ (100 MHz, Flash chromatography (petroleum ether/EtOAc 2 : 1 + 0.1%
C
CDCl
3
/MeOD 1 : 1) 162.1, 160.1, 154.6, 153.9 (4 C, C-1 MU, C-3 Et
3
N) afforded 24 (466 mg, 76%) as a white foam. [α]
D
−174.9
MU, C-6 MU, C-8 MU), 125.9 (1 C, C-5 MU), 115.0 (1 C, C-0 (c 1.01 in CHCl
3
); δ (400 MHz, CDCl ) 7.53 (1 H, d, J4,5 8.6,
H
3
MU), 113.8 (1 C, C-4 MU), 111.9 (1 C, C-7 MU), 104.0 (1 C, C-2 H-5 MU), 7.44 (2 H, m, o-Ph), 7.32 (1 H, m, p-Ph), 7.15 (2 H, m,
MU), 100.8 (1 C, C-1), 89.3 (1 C, d, J4,F 180.7, C-4), 73.7 (1 C, d, m-Ph), 7.01 (2 H, m, H-2 MU, H-4 MU), 6.20 (1 H, d, J7,Me 1.7,
J3,F 19.0, C-3), 72.3 (1 C, d, J2,F 8.6, C-2), 62.7 (1 C, d, J5,F 28.2, H-7 MU), 5.49 (1 H, m, H-4), 5.42 (1 H, d, J1,2 6.7, H-1), 4.42
C-5), 18.0 (1 C, Me MU); δ (376 MHz, CDCl /MeOD 1 : 1) (1 H, dd, J5ax,5eq 13.4, J4,5ax/eq 4.7, H-5ax/eq), 4.23 (1 H, dd,
F
3
+
+
−
C
198.8; ESI HRMS [M
+
H] m/z 311.0925 calcd for
J
2,3 10.8, J3,4 8.3, H-3), 4.03 (1 H, dd, H-2), 3.85 (1 H, dd, J4,5ax/eq
4.9, H-5ax/eq), 3.39, 3.33 (6 H, 2 s, OMe BDA), 2.43 (3 H, d, Me
4-deoxy-4-fluoro-2,3-O-(2′,3′- MU), 1.39, 1.36 (6 H, 2 s, Me BDA); δ (100 MHz, CDCl ) 194.1
15
H
16FO
6
, found: 311.0924.
4
.2.5 4-Methylumbelliferyl
C
3
dimethoxybutane-2′,3′-diyl)-α-L-arabinopyranoside (20). The (1 C, CvS), 161.1, 159.5, 154.8, 153.3, 152.3 (5 C, Cquat Ph, C-1
compound was prepared from either 5b or 10. From 5b: MU, C-3 MU, C-6 MU, C-8 MU), 129.6 (2 C, o-Ph), 126.7 (1 C,
Alcohol 5b (40 mg, 0.09 mmol) was subjected to the general p-Ph), 125.5 (1 C, C-5 MU), 121.8 (1 C, m-Ph), 115.1 (1 C, C-0
procedure for the fluorination with DAST (method B). Flash MU), 113.6 (1 C, C-4 MU), 112.9 (1 C, C-7 MU), 104.6 (1 C, C-2
3
chromatography (toluene/EtOAc 4 : 1 + 0.1% Et N) afforded 20 MU), 99.7 (2 C, Cquat BDA), 98.7 (1 C, C-1), 79.6 (1 C, C-4), 68.7
(
16 mg, 41%) and elimination product 21 (22%). From 10: (1 C, C-2), 68.3 (1 C, C-3), 63.4 (1 C, C-5), 48.2, 48.1 (2 C, OMe
+
Triflate 10 (0.114 g, 0.21 mmol) was subjected to the general BDA), 18.7 (1 C, Me MU), 17.6, 17.5 (2 C, Me BDA); ESI HRMS
+
procedure for the fluorination with TBAF. 20 (32 mg, 36%) was [M + H] m/z 559.1632 calcd for C28
isolated along with 21 (15%). 20: [α]D −59.9 (c 0.98 in CHCl3); 4.2.8 4-Methylumbelliferyl 4-deoxy-2,3-O-(2′,3′-dimethoxy-
(400 MHz, CDCl ) 7.52 (1 H, d, J4,5 8.7, H-5 MU), 7.01 (2 H, butane-2′,3′-diyl)-β-D-xylopyranoside (26). 24 (0.46 g,
31
H O10S, found: 559.1629.
δ
H
3
m, H-2 MU, H-4 MU), 6.20 (1 H, d, J7,Me 1.3, H-7 MU), 5.18 (1 H, 0.82 mmol) was subjected to the general procedure for the
d, J1,2 7.9, H-1), 4.81 (1 H, dm, J4,F 52.2, H-4), 4.30 (1 H, dd, radical deoxygenation. Flash chromatography (petroleum
J
5ax,5eq = J5eq,F 12.1, J4,5eq 1.7, H-5eq), 4.25 (1 H, dd, J2,3 10.6, ether/EtOAc 2 : 1 + 0.1% Et
H-2), 3.94 (1 H, ddd, J3,F 29.2, J3,4 2.5, H-3), 3.81 (1 H, dd, J5ax,F white foam. [α] −86.9 (c 1.08 in CHCl
4.6, J4,5ax < 1, H-5ax), 3.39, 3.33 (6 H, 2 s, OMe BDA), 2.42 (3 H, 7.50 (1 H, d, J4,5 8.6, H-5 MU), 6.98 (2 H, m, H-2 MU, H-4 MU),
d, Me MU), 1.42, 1.35 (6 H, 2 s, Me BDA); δ (100 MHz, CDCl 6.17 (1 H, s, H-7 MU), 5.10 (1 H, d, J1,2 7.8, H-1), 4.12 (1 H, m,
61.0, 159.6, 154.8, 152.3 (4 C, C-1 MU, C-3 MU, C-6 MU, C-8 H-5ax/eq), 3.91 (1 H, m, H-3), 3.75 (1 H, dd, J2,3 9.6, H-2), 3.66
MU), 125.4 (1 C, C-5 MU), 115.1 (1 C, C-0 MU), 114.1 (1 C, C-4 (1 H, m, H-5ax/eq), 3.38, 3.31 (6 H, 2 s, OMe BDA), 2.41 (3 H, s,
MU), 112.9 (1 C, C-7 MU), 104.2 (1 C, C-2 MU), 100.5, 99.9 (2 C, Me MU), 1.89 (2 H, m, H-4), 1.34 (6 H, s, Me BDA); δ
quat BDA), 98.6 (1 C, C-1), 86.5 (1 C, d, J4,F 184.8, C-4), 68.4 (100 MHz, CDCl ) 161.1, 159.8, 154.8, 152.4 (4 C, C-1 MU, C-3
1 C, d, J3,F 17.2, C-3), 66.3 (1 C, d, J2,F 1.6, C-2), 65.8 (1 C, d, J5,F MU, C-6 MU, C-8 MU), 125.4 (1 C, C-5 MU), 114.9 (1 C, C-0
0.4, C-5), 48.2, 48.0 (2 C, OMe BDA), 18.7 (1 C, Me MU), 17.6 MU), 113.9 (1 C, C-4 MU), 112.7 (1 C, C-7 MU), 104.2 (1 C, C-2
3
N) afforded 26 (206 mg, 62%) as a
D
3
); δ (400 MHz, CDCl
H
3
)
3
C
3
)
1
C
C
(
2
3
+
+
(2 C, Me BDA); δ
F
(376 MHz, CDCl
3
) −204.1; ESI HRMS [M + H]
MU), 99.9, 99.8 (2 C, Cquat BDA), 98.6 (1 C, C-1), 71.4 (1 C, C-2),
67.4 (1 C, C-3), 62.9 (1 C, C-5), 48.1, 47.9 (2 C, OMe BDA), 29.6
m/z 425.1606 calcd for C H FO , found: 425.1607.
21
26
8
Org. Biomol. Chem.
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