Chemistry of Natural Compounds, Vol. 38, No. 2, 2002
STRUCTURE OF DIPSACOBIOSIDE
A. A. Akimaliev, M. I. Isaev, and N. K. Abubakirov*
UDC 547.918:547.914.4
1
The structure of dipsacobioside ( ), which was isolated from roots of Dipsacus azureus Schrenk (Dipsacaceae), has
been reported [1]. However, an incorrect identification of the methylated monosacchrides made it necessary to revise the
2
structure of this glycoside. We studied samples of dipsacobioside and dipsacoside B ( ) [2] isolated by A. A. Akimaliev.
COOH
O
HO
O
O
O
CH OH
2
CH
OH
OH
3
OH
OH
1
PMR spectra of dipsacoside B (100 MHz, C D N, δ, ppm, 0 = HMDS, J/Hz): 0.72 (2×CH , s), 0.84 (CH , s), 0.88
5
5
3
3
3
3
(CH , s), 0.95 (CH , s), 1.03 (CH , s), 1.45 (CH L-rhamnose, d, J = 6), 4.80 (H-1 of terminal D-glucose, d, J = 7), 4.91 (H-1
of L-arabinose, d, J = 6), 5.22 (H-12, br.s), 5.94 (H-1 of L-rhamnose, br.s), 5.97 (H-1 of D-glucose on C-28, d, J = 8).
3
3
3
3
3
3
3
3
Methylation of dipsacoside B according to Hakomori [3] gave permethylate . PMR spectrum of (100 MHz, C D N,
5
5
3
δ, ppm, 0 = HMDS, J/Hz): 0.79-1.14 (6×CH , s), 1.30 (CH of L-rhamnose, d, J = 6), 3.21-3.55 (13×CH O, s), 4.40 (H-1 of
terminal D-glucose, d, J = 7), 4.50 (H-1 of L-arabinose, d, J = 6), 5.21 (H-12, m), 5.49 (H-1 of L-rhamnose, br.s), 5.68 (H-1
3
3
3
3
3
3
3
of D-glucose on C-28, d, J = 8). GC [4] detected in the methanolysis products of , as expected, 2,3,4-tri-OMe-L-rhamnose
(Trel 0.50, 0.56), 3,4-di-OMe-L-arabinose (Trel 0.68, 0.81), 2,3,4,6-tetra-OMe-D-glucose (Trel 1.00, 1.25), and 2,3,4-tri-OMe-D-
glucose (Trel 1.18, 1.43).
4
4
Base hydrolysis of dipsacoside B gave kalopanax-saponin A ( ) [5], which is called [2, 6] dipsacoside A. is identical
to dipsacobioside according to chromatographic behavior in various solvent systems and PMR spectral parameters [1].
1
Thus, the structure of that was assigned to dipsacobioside is erroneous. Dipsacoside A, dipsacobioside, like
4
kalopanax-saponin A, has formula .
______
*Deceased.
S. Yu. Yunusov Institute of the Chemistry of Plant Substances, Tashkent, fax (99871) 120 64 75. Translated from
Khimiya Prirodnykh Soedinenii, No. 2, p. 166, March-April, 2002. Original article submitted March 25, 2002.
0009-3130/02/3802-0202$27.00 ©2002 Plenum Publishing Corporation
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