T. Rosenau et al.
FULL PAPER
(
(
1
CH
C-2ЈЈ), 77.0 (C-1Ј), 77.8/77.9 (C-3ЈЈ /C-5ЈЈ), 83.1 (C-2Ј), 104.2 (C-
ЈЈ), 110.3 (C-3), 115.2 (C-2), 152.1 (C-4), 160.7 (C-1), 165.4 (COO) 2), 77.9/78.0 (C-3/C-5), 104.3 (C-1), 127.1 (Ph-4), 129.3/130.0 (Ph-
2
in Et), 62.3 (C-6ЈЈ), 71.1 (C-3Ј), 71.5 (C-4ЈЈ), 73.3 (C-4Ј), 75.1 1 H, 1-H), 7.15–7.26 (m, 5 H, Ph) ppm. 13C NMR (DMSO): δ =
37.2 (Ph-CH ), 62.7 (C-6), 71.6 (C-4), 71.7 (Ph-CH -CH ), 75.0 (C-
2
2
2
ppm. C18
H 6.31.
H
26
O
11 (418.40): calcd. C 51.67, H 6.26; found C 51.62, 2/6, Ph-3/5), 140.0 (Ph-1) ppm. C14
20 6
H O (284.31): calcd. C 59.14,
H 7.09; found C 59.14, H 7.14.
Synthesis of β-Glucopyranosides 18–23 and α-Glucopyranoside 24:
The glucosides 18–24 were prepared according to standard pro-
cedures, starting from commercially available pentaacetylbromo--
glucose as the glycosyl donor and the free alcohols as the respective
glycosyl acceptors.
2
0
Benzyl β-Glucopyranoside (23): [α]
D
= –58.4 (c = 1.00, MeOH),
1
m.p. 121–122 °C (methanol). H NMR (300 MHz, CD OD): δ =
.22–3.38 (m, 4 H, 2-H, 3-H, 4-H, 5-H), 3.69 (dd, J = 12.0, J =
.5 Hz, 1 H, 6-H2A), 3.89 (dd, J = 12.0, J = 2.1 Hz, 1 H, 6-H2B),
.35 (d, J = 7.6 Hz, 1 H, 1-H), 4.65 (d, J = 11.8 Hz, 1 H, Ph-
3
2
3
3
5
4
2
3
3
2
2
-(2-Furyl)ethyl β-Glucopyranoside (18): [α]2
D
0
= –45.2 (c = 1.0,
CH2A), 4.93 (d, J = 11.8 Hz, 1 H, Ph-CH2B), 7.23–7.43 (m, 5 H,
2
1
13
MeOH), m.p. 95–98 °C (methanol). H NMR (300 MHz, CD
δ = 2.75 (m, 2 H, Fu-CH
H), 3.71 (m, 1 H, Fu-CH
3
OD): Ph) ppm. C NMR (DMSO): δ = 62.8 (C-6), 71.6 (C-4), 71.7 (Ph-
2
), 3.20–3.37 (m, 4 H, 2-H, 3-H, 4-H, 5- CH ), 75.1 (C-2), 78.0/78.05 (C-3/C-5), 103.2 (C-1), 128.7 (Ph-4),
2
2
3
2
-CH2A), 3.65 (dd, J = 12.0, J = 5.5 Hz, 129.2/129.25 (Ph-2/6, Ph-3/5), 139.0 (Ph-1) ppm. C H O
13 18 6
2
3
1
H, 6-H2A), 3.84 (dd, J = 12.0, J = 2.0 Hz, 1 H, 6-H2B), 3.89
(270.28): calcd. C 57.77, H 6.71; found C 58.05, H 6.88.
3
(
m, 1 H, Fu-CH
2
-CH2B), 4.34 (d, J = 7.7 Hz, 1 H, 1-H), 6.25 (d,
3
3
20
J = 2.7 Hz, 1 H, Fu), 6.40 (m, 1 H, Fu), 7.45 (d, J = 1.3 Hz, 1
2-(2-Furyl)ethyl α-Glucopyranoside (24): [α]
D
= 2.6 (c = 1.00,
OD): δ = 2.74
H, Fu) ppm. 13C NMR (DMSO): δ = 32.1 (Fu-CH
1
), 62.6 (C-6), MeOH), colorless wax. H NMR (300 MHz, CD
), 75.0 (C-2), 77.9/78.0 (C-3/C-5), (m, 2 H, Fu-CH ), 3.22–3.30 (m, 1 H, 4-H), 3.37 (dd, J = 9.1,
04.1 (C-1), 110.7, 111.3, 142.5, 153.6 (Fu) ppm. C12
3.8 Hz, 1 H, 2-H), 3.52 (ddd, J = 9.8, 6.7, 1.5 Hz, 1 H, 5-H), 3.60
3
2
3
7
1
1.6 (C-4), 70.0 (Fu-CH
2
-CH
2
2
3
18 7
H O
3
(274.27): calcd. C 52.55, H 6.62; found C 52.63, H 6.68.
2
(t, J = 9.1 Hz, 1 H, 3-H), 3.72 (m, 1 H, Fu-CH -CH2A), 3.65 (dd,
J = 11.8, J = 6.7 Hz, 1 H, 6-H2A), 3.79 (dd, J = 11.8, J = 1.5 Hz,
2
-CH2B), 4.65 (d, J = 3.7 Hz, 1
H, 1-H), 6.29 (m, 1 H, Fu), 6.39 (m, 1 H, Fu), 7.37 (m, 1 H, Fu)
ppm. C NMR (DMSO): δ = 32.6 (Fu-CH
), 68.1 (Fu-CH -CH ), 73.1 (C-2), 73.7 (C-5), 75.2 (C-3), 100.3
C-1), 108.9, 111.0, 144.0, 153.1 (Fu) ppm. C12 (274.27):
calcd. C 52.55, H 6.62; found C 52.70, H 6.89.
2
3
2
3
2
1
-(2-Furyl)methyl β-Glucopyranoside (Furfuryl β-Glucopyranoside,
3
1
H, 6-H2B), 3.90 (m, 1 H, Fu-CH
9): [α]2
0
= –35.5 (c = 1.00, MeOH), colorless wax. 1H NMR
OD): δ = 3.16–3.38 (m, 4 H, 2-H, 3-H, 4-H, 5-H),
D
(300 MHz, CD
3
1
3
2
), 62.4 (C-6), 71.6 (C-
2
3
2
3
.67 (dd, J = 12.0, J = 5.5 Hz, 1 H, 6-H2A), 3.88 (dd, J = 12.0,
4
2
2
3
3
J = 2.0 Hz, 1 H, 6-H2B), 4.33 (d, J = 7.7 Hz, 1 H, 1-H), 4.63 (d,
(
18 7
H O
2
J = 12.7 Hz, 1 H, Fu-CH2A), 4.80 (d, 2J = 12.7 Hz, 1 H, Fu-
CH2B), 6.37 (m, 1 H, Fu), 6.41 (m, 1 H, Fu), 7.47 (m, 1 H, Fu)
ppm. 13C NMR (DMSO): δ = 62.8 (C-6), 63.4 (Fu-CH
), 71.6 (C-
), 75.0 (C-2), 78.01/78.04 (C-3/C-5), 102.8 (C-1), 110.9, 111.4,
2
Thermal “Endwise Peeling” of Model Compounds 15 and 18–24: The
respective model compound (1 mmol) was dissolved in a mixture
of 1,4-dioxane and water (1:1, v/v, 50 mL), ethyl acetoacetate (1,
56 mg, 0.15 mL, 1.2 mmol) was added, and the mixture was
heated at reflux. After consumption of the model compound (TLC
4
1
44.1, 152.6 (Fu) ppm. C11
H
16
O
7
(260.25): calcd. C 50.77, H 6.20;
found C 50.91, H 6.05.
1
3
-(2-Furyl)propyl β-Glucopyranoside (20): [α]2
D
0
= –5.0 (c = 1.00,
1
MeOH), m.p. 88–90 °C (methanol). H NMR (300 MHz, CD
δ = 1.82 (m, 2 H, CH -CH -CH ), 2.58 (t, 2 H, Fu-CH
.37 (m, 4 H, 2-H, 3-H, 4-H, 5-H), 3.39 (m, 1 H, CH
-CH2A-O), analysis, and the reaction mixture was three times co-evaporated
3
OD): control) or after 6 h, respectively, the mixture was cooled to room
), 3.20–
temp. An aliquot (100 µL) was withdrawn for CE and GC-MS
2
2
2
2
3
2
2
3
2
3
.65 (dd, J = 12.0, J = 5.5 Hz, 1 H, 6-H2A), 3.84 (dd, J = 12.0,
with toluene (3ϫ20 mL), finally concentrated to a volume of about
-CH2B-O), 4.34 (d, J 0.5 mL, and purified by chromatography on silica gel (toluene/ethyl
2
3
3
J = 2.0 Hz, 1 H, 6-H2B), 3.56 (m, 1 H, CH
7.5 Hz, 1 H, 1-H), 6.36 (m, 1 H, Fu), 6.42 (m, 1 H, Fu), 7.47
=
(
(
acetate, 5:1, v/v). Tetrahydroxybutylfuran 4 was recovered from 15
m, 1 H, Fu) ppm. 13C NMR (DMSO): δ = 27.8 (Fu-CH
Fu-CH -CH ) 62.5 (C-6), 63.1 (Glc-O-CH
), 32.0 in 82% yield, from 2-(2-furyl)ethyl β-glucopyranoside (18) in 96%
2
), 71.5 (C-4), 75.3 (C-
yield, from furfuryl β-glucopyranoside (19) in 35% yield, from 3-
2
2
2
2
), 77.9/78.1 (C-3/C-5), 103.1 (C-1), 109.9, 111.3, 144.6, 152.7 (Fu) (2-furyl)propyl β-glucopyranoside (20) in 15% yield, and from 2-
ppm. C13
H
20
O
7
(288.30): calcd. C 54.16, H 6.99; found C 54.01, H
(2-furyl)ethyl α-glucopyranoside (24) in 3% yield. Model com-
pounds 21–23 did not produce any furan 4, nor showed any conver-
sion of the starting material. The recovery of the starting material
was 96% in the case of 21 and 23, 95% from 22, and 37% from
7.09.
-(Tetrahydro-2-furyl)ethyl β-Glucopyranoside (21): [α]2
0
= –12.1 (c
1.00, MeOH), m.p. 35–36 °C (methanol). H NMR (300 MHz,
OD): δ = 1.59 (m, 2 H, THF-CH ), 1.78–2.14 (m, 4 H, THF),
.23–3.40 (m, 4 H, 2-H, 3-H, 4-H, 5-H), 3.42 (m, 1 H, CH -CH2A
O), 3.50–3.61 (m, 1 H, CH
-CH2B-O), 3.67 (dd, 2J = 11.8, 3J =
.8 Hz, 1 H, 6-H2A), 3.78–3.92 (m, 2 H, THF), 3.87 (dd, J = 11.8,
2
=
CD
3
D
1
24. According to the above procedure, (tetrahydrofuranyl)furan 15
3
2
also reacted with benzyl acetoacetate (16, 0.23 g, 1.2 mmol) instead
of ethyl acetoacetate (1). Chromatography on silica gel (toluene/
ethyl acetate, 7:1, v/v) provided furan 17 as a white solid (296 mg,
2
-
2
2
5
88%).
3
3
J = 2.4 Hz, 1 H, 6-H2B), 4.12–4.20 (m, 1 H, THF), 4.36 (d, J =
13
7
7
7
.0 Hz, 1 H, 1-H) ppm. C NMR (DMSO): δ = 25.2, 31.6, 66,4,
8.2 (THF), 36.4 (THF-CH ), 59.0 (THF-CH -CH ) 62.5 (C-6),
1.4 (C-4), 75.3 (C-2), 77.9/78.0 (C-3/C-5), 104.0 (C-1) ppm.
(278.30): calcd. C 51.79, H 7.97; found C 52.01, H 7.89.
Benzyl 2-Methyl-5-(1,2,3,4-tetrahydroxybutyl)furan-3-carboxylate
2
2
2
2
0
1
(
17): [α]
NMR (300 MHz, CD
m, 4 H), 4.88 (d, 1 H, 1-H in Bu), 5.25 (s, 2 H, Bn), 6.61 (s, 1 H,
D
= –5.0 (c = 1.00, MeOH), m.p. 140–141 °C (ethanol). H
3
OD): δ = 2.53 (s, 3 H, CH -Fu), 3.50–3.82
3
12 22 7
C H O
(
-Phenylethyl β-Glucopyranoside (22): [α]20
= –30.3 (c = 1.00,
MeOH), m.p. 122–123 °C (methanol). 1H NMR (300 MHz,
CD OD): δ = 2.93 (“t”, 2 H, Ph-CH ), 3.16–3.39 (m, 4 H, 2-H, 3- Bu), 70.4 (C-3 in Bu), 74.2 (C-2 in Bu), 108.4 (C-4), 115.1 (C-3),
H, 4-H, 5-H), 3.59–3.79 (m, 1 H, Ph-CH
CH in Fu), 7.30–7.41 (m, 5 H, Bn) ppm. C NMR (CD
13.9 (CH in Fu), 64.9 (C-4 in Bu), 66.9 (CH , Bn), 68.0 (C-1 in
13
2
D
3
OD): δ =
3
2
3
2
2
2
2
-CH2A), 3.65 (dd, J =
129.1 (C-2/6, Bn), 129.2 (C-4, Bn), 129.6 (C-3/5, Bn), 137.8 (C-1,
3
3
1
2.0, J = 5.5 Hz, 1 H, 6-H2A), 3.86 (dd, J = 12.0, J = 2.0 Hz, 1 Bn), 155.4 (C-2), 158.9 (C-5), 165.5 (COO) ppm. C17
20 7
H O
3
H, 6-H2B), 4.05–4.13 (m, 1 H, Ph-CH
2
-CH2B), 4.30 (d, J = 7.7 Hz, (336.34): calcd. C 60.71, H 5.99; found C 60.89, H 6.02.
© 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Eur. J. Org. Chem. 2008, 475–484
482 www.eurjoc.org