Journal of Asian Natural Products Research
1059
0
0
0
3
.3 Isolation and purification
Twelve liters of the culture medium
fungus and agar medium) were extracted
with ethyl acetate to afford a crude extract
2 g) after the removal of the solvent under
31.5 (C-8 ), 29.2 (C-9 ), 28.8 (C-10 ), 31.1
(C-11 ), 22.3 (C-12 ), 13.5 (C-13 ), 102.8
0 0 0
00 00 00
C-1 ), 70.9 (C-2 ), 75.5 (C-3 ), 68.6 (C-
(
(
0
0
00 00
4
FAB-MS (2ve mode): m/z 589.3009
), 73.0 (C-5 ), and 61.3 (C-6 ); HR-
(
2
[
M 2 H]
(calcd for C H O ,
32 45 10
reduced pressure. The combined concen-
trated extract (2 g) was column-chromato-
graphed on silica gel by eluting with a
gradient of n-hexane/ethyl acetate (100:0–
5
89.3012).
3
.3.2 Acid hydrolysis of 1
0
:100) to obtain seven fractions (A–G).
A solution of 1 (4 mg) in MeOH (5 ml)
containing 1 N HCl (4 ml) was refluxed for
Fraction F (35.0 mg) on further repeated
silica gel column chromatography eluted
with an isocratic mobile phase system of
4 h, concentrated under reduced pressure,
and diluted with H O (8 ml). It was
2
3
0% ethyl acetate in n-hexane yielded 1
22.0 mg). Fraction C (45.0 mg) on further
extracted with EtOAc and the residue
recovered from the organic phase was
found to be a mixture of products. The
aqueous phase was concentrated and
D-galactose was identified by the sign of
(
repeated silica gel column chromatog-
raphy with 8% ethyl acetate in n-hexane
yielded 2 (11 mg), whereas 3 (2.5 mg) was
purified from fraction D (24.0 mg) by
silica gel column chromatography eluting
with 15% ethyl acetate in n-hexane.
2
0
its optical rotation (½aꢀ þ79.5). It was
D
also confirmed based on the retention time
of its TMS ether (a-anomer 3.8 min,
b-anomer 5.2 min) with that of standard
[18] in GC.
3
.3.1 Depsitinuside (1)
Colorless amorphous powder (22.0 mg);
IR (KBr) nmax: 3475 (OH), 3120 and 2920
(
CZH), 1720 (CvO) and 1610, 1560
1
Acknowledgements
(
aromatic ring);
00 MHz): d 6.41 (1H, br s, H-4), 6.38
H NMR (CDCl3,
Muhammad Saleem is thankful to the Alax-
ander von Humboldt (AvH) Foundation,
Germany, for financial support. He is also
obliged to Third World Academy of Science
5
0
0
(
(
(
1H, br s, H-6 ), 6.36 (1H, br s, H-2 ), 6.29
1H, br s, H-4 ), 6.22 (1H, br s, H-6), 4.58
0
(
TWAS), Italy, for providing some of the basic
00
1H, d, J ¼ 7.6 Hz, H-1 ), 3.69 (1H, d,
laboratory facilities in Chemistry Department
of IUB. We thank Kathrin Meier for excellent
technical assistance.
0
0
J ¼ 1.5 Hz, H-4 ), 3.66 (1H, dd, J ¼ 10.5,
0
0
3
2
3
.5 Hz, H -6 ), 3.56 (1H, t, J ¼ 7.6 Hz, H-
b
0
0
00
), 3.54 (1H, dd, J ¼ 10.5, 4.8 Hz, H -6 ),
a
00
.42 (1H, dd, J ¼ 7.6, 1.5, H-3 ), 3.36 (1H,
References
0
0
m, H-5 ), 2.57 (1H, dt, J ¼ 11.5, 7.5 Hz,
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a
0
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1
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1
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3
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1
14.6 (C-2), 156.6 (C-3), 101.3 (C-4),
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(
C-8), 31.5 (C-9), 28.9 (C-10), 31.1 (C-
0
0
0
1
1
1
1), 22.3 (C-12), 13.5 (C-13), 157.4 (C-1 ),
0
[
[
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0
06.0 (C-2 ), 151.2 (C-3 ), 112.3 (C-4 ),
0
0
45.3 (C-5 ), 113.0 (C-6 ), 35.5 (C-7 ),