Glucuronide saponins

CS013 Sagesak, Y. M., T. Uemura, N. Watanabe, K. Sakata and J. Uzawa. A new glucuronide saponin from tea leaves (Camellia sinensis var. sinensis). Biosci Biotech Biochem 1994 58(11) 2036-2040. 

Yoshikawa, M. "Bioactive Saponins and Glycosides VI... The Structure-Requirement in Oleanolic Acid Glucuronide-Saponins for the Inhibitory Activity," Chem Pharm Bulletin, 1996 Vol, 44 (10), PP. 1915-1922. 

It was found that the 3-0-glucuronide moiety and the 28-carboxyl group in oleanolic acid glucuronide saponin were required to exert the inhibitory activity. Elatoside A and B were found to show potent inhibitory activity on ethanol absorption. 

N-(D-Threo- and racemic erythro-3-amino-2-hydroxy-butanoyl)-2, 3 -dideoxykanamycin A has been prepared using a standard esterification procedure with the corresponding azido-hydroxy-butanoic acid. Glucuronide saponins have been used to furnish paromamine and ribostamycin by means of lead tetraacetate or anodic oxidative decarboxylation procedures. Phase-sensitive 2D COSY spectra... 

The distribution and structural elucidation of saponins have been reviewed. Glucuronides with a free carboxy-group and carbohydrate residues at C-2 and C-4 are readily cleaved with acetic anhydride in refluxing pyridine to give the genuine aglycone (see Vol. 7, p. 145). Details of the mass spectra of a series of permethylated oleanane saponins have been discussed. 

Some oleanolic acid-type saponins were known to exhibit similar hepatoprotective activity [4, 7, 32, 42, 43, 44-46]. We also reported the hepatoprotective activity of Palustroside in which has a glucosyl carboxy group at C-28 [47]. As a part of our continuing study, we examined the preventive effects of five oleanolic acid-type glucuronides (90-95), Fig. (8), isolated from Dumasia tnmcata (Table 3) [48]. 

Edible Beans With regard to saponins of the most important soybean, Kitagawa s chemical studies are well known [19]. In addition, various pharmacological actions were reported about soybean [20-24]. We have examined several beans as listed Table 7, that is, they are kidney bean, haricot bean, cowpea, azuki bean and so on and listed yields of crude oleanene triterpene glucuronides [25]. The HPLC profiles of oleanene glucuronides in some edible beans are shown in Fig. 4. Almost of beans include soyasaponin 1. 

Li B, Abliz Z, Fu GM, Tang MJ, Yu SS. Characteristic fragmentation behavior of some glucuronide-t5q)e triterpenoid saponins using electrospray ionization tandem mass spectrometry. Rapid Commun Mass Spectrom 2005 19 381-390. 

Details of the selective cleavage of o-glucuronidic linkages in saponins have been published (see Vol. 10, p. 117). A modified procedure for determining the sites of attachment of hexuronic acid residues in methylated acidic polysaccharides by base-catalysed degradation has been modelled on experiments with the methylated aldobiouronic acid derivative (430), which eliminated methyl 2,3,4-tri-O-methyl-p-D-glucopyranoside (89%) on treatment with sodium methylsulphinyl-methanide in DMSO at room temperature. When this procedure is applied to... 

The formulas of a typical neutral saponin, sarsasaponin from Radix sarsaparillae 25), and the acid saponin of sugar beets Beta vulgaris), the glucuronide of oleanolic acid 26), are given. 

A new method for selectively cleaving the D-glucuronidic linkages of saponins is based on oxidative decarboxylation of per-C>-methylated derivatives with lead tetra-acetate in benzene, followed by release of the aglycone with base (Scheme... 

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