Genuine Glycosides Research Articles

Ginsenoside Rh4, A Genuine Dammarane Glycoside from Korean Red Ginseng

A genuine glycoside, named ginsenoside Rh4, was isolated from Korean red ginseng (Panax ginseng C. A. Meyer) through repeated column chromatography, and its chemical structure was established to be 6-O-beta-D-glucopyranosyldammar-20(22),24-diene-3 beta,6 alpha,12 beta-triol by spectral and chemical methods. The stereochemistry of a double bond at C-20(22) of ginsenoside Rh4 was characterized as (E) from a NOESY experiment in the 1H-NMR of the aglycone. Cytotoxic activities of ginsenoside Rh4 and its aglycone against cancer cell lines were evaluated by use of the SRB method.

Massenspektrometrie von flavonoid-o-glykosiden—II

MS-analysis of more than 20 naturally occurring flavonoid-mono-, di- and triglycosides as isopropyliden-permethyl-derivatives allows: (1) MS-differentiation between stereoisomeric sugar moieties, (2) determination of the interglycosidic linkages in di- and tri-glycoside with the aid of improved M +-peaks and (3) differentiation between the furanoid and pyranoid ring form of sugars in the genuine glycosides.

Die Pregnanderivate der Samen von Dregea abyssinica (HOCHST.) K. Schum. (Asclepiadaceae). I. Isolierungen Glykoside und Aglykone, 304. Mitteilung

AbstractThe seeds of Dregea abyssinica (HOCHST.) K. Schum. are very rich in glycosides. These consist of a complicated mixture of ester glycosides, cardenolides are absent. All these glycosides are derived from only the two known pregnane derivatives drevogenin P and Drevogenin D. In the glycosides the latter are esterified with different acids (acetic, isovaleric, α‐hydroxyisovaleric and tiglic acid) and glycosidically linked to different 2‐deoxy‐sugars which in part carry 3‐O‐methyl‐6‐deoxy‐D‐allose and terminal D‐glucose. After mild acidic hydrolysis 5 crystalline sugars and 6 crystalline aglycones could be isolated. The sugars were identified as D‐cymarose, asclepobiose, pachybiose, drebyssobiose and «sugar T» (formerly found in Dregea volubilis). The following aglycones were obtained: drevogenin A, drevogenin B, and four new compounds called drebyssogenin F, G, J and K. The latter was a mixture of two components (K1 and K2). From the original mixture four genuine glycosides could be isolated (the drebyssosides 1, 2, 3 and 4). Of these the drebyssosides 1 and 3 were obtained crystalline, drebyssoside 2 in amorphous but pure form and drebyssoside 4 as a mixture of mainly two closely related components. The probable structures of the new substances (drebyssobiose, sugar T, the four drebyssogenins and the four drebyssosides) are reported in the following publication.