Triterpenoid saponin

Triterpenoid saponins are rare in monocotyledons, but abundant in many dicotyledonous 

The roots of the herbaceous plants Panax ginseng (Araliaceae) from China, Korea, and Russia, and related Panax species, e.g. P. quinquefolium (American ginseng) from the USA 

The triterpenoid skeletons may be subjected to a variety of structural modifications as already illustrated. However, the particular modifications considered in this section are those that lead to loss of several skeletal carbon atoms. Preeminent amongst such degraded triterpenoids are 

The interesting biological properties shown by many saponins, coupled with improvements in spectroscopic methods of structure determination have led to the increased study of this class of compound. The following papers deal with saponins and prosapogenins which are based on known triterpenoids of the following groups dammarane-euphane,158 lupane,159 oleanane,160 and ursane.161 

Desorption/chemical ionization mass spectrometry is a useful technique for the investigation of underivatized polar and involatile compounds such as triterpenoid saponins.162 The cleavage of saponins by anodic oxidation has been investigated,163 as has the glycosidation of triterpenoids.164 

Cattel, L. Delprino, and A. Dietsch, Gazz. Chim. Ital., 1979, 109, 705. 

Hostettmann, J. Doumas, and M. Hardy, Helv. Chim. Acta, 1981, 64, 297. 

Kitagawa, T. Kamigauchi, H. Ohmori, and M. Yoshikawa, Chem. Pharm. Bull., 1980, 28, 3078. 

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Note that the plant is known to abound with triterpenoid saponins (44,45). Is the plant holding GABAergic activity One wonders. 

Pan RL, Chen DH, Si JY, Zhao XH, Shen LG. Studies on the new triterpenoid saponin of the aerial part of Cimicifuga foetida. Zhongguo Zhong Yao Za Zhi 2003 8 230-232. 

In 2006, Milosavljevic and co-workers64 reported a study of the complete 4H and 13C NMR assignment of a new triterpenoid saponin, leucantho-side-A (13), from Cephalaria leucantha L. In the course of determining the structure and assigning the spectra, the authors made extensive use of the normal ensemble of 2D NMR experiments in use for the characterization of natural product structures HSQC, HMBC, DQF-COSY, TOCSY, and NOESY. The authors supplemented the aforementioned list of experiments with 2D /-resolved, DINE-(Double INEPT-Edited)-HSQC, and INADEQUATE spectra. The authors made no mention of the use of the connectivity information derived from the 1,1-ADEQUATE spectrum in the assembly of the triterpene nucleus of the molecule but reported extensive tabulations of the 1,1-ADEQUATE correlations that were used to sequence and assign the saccharide resonances of the tri- and di-saccharide sub-units, 14 and 15, respectively, linked to the triterpene nucleus. 

SCHEME 19. Retrosynthetic pathway for the glycon of the anti-Leishmania triterpenoid saponin 81. 

V. K. Rajput and B. Mukhopadhyay, Concise synthesis of a pentasaccharide related to the anti-leishmanial triterpenoid saponin isolated from Maesa balansae, J. Org. Chem., 73 (2008) 6924—6927. 

HARIDAS, V., HIGUCHI, M., JAYATILAKE, G.S., BAILEY, D., MUJOO, K., BLAKE, M.E., ARNTZEN, C.J., GUTTERMAN, J.U., Avicins Triterpenoid saponins from Acacia victoriae (Bentham) induce apoptosis by mitochondrial perturbation, Proc. Natl. Acad. Sci., USA, 2001, 98, 5821-5826. 

A more detailed understanding of the biochemical pathways and enzymes involved in saponin biosynthesis will facilitate the development of plants with altered saponin content. In some cases, enhanced levels of saponins or the synthesis of novel saponins may be desirable (for example, for drug production 4 or improved disease resistance3,5,6), while for other plants, reduction in the content of undesirable saponins would be beneficial (for example, for legume saponins that are associated with antifeedant properties in animal feed7). This chapter is concerned with recent progress that has been made in the characterization of the enzymes and genes involved in the synthesis of these complex molecules and focuses on triterpenoid saponins. 

Triterpenoid saponins are synthesized via the isoprenoid pathway.4 The first committed step in triterpenoid saponin biosynthesis involves the cyclization of 2,3-oxidosqualene to one of a number of different potential products (Fig. 5.1).4,8 Most plant triterpenoid saponins are derived from oleanane or dammarane skeletons although lupanes are also common 4 This cyclization event forms a branchpoint with the sterol biosynthetic pathway in which 2,3-oxidosqualene is cyclized to cycloartenol in plants, or to lanosterol in animals and fungi. 

HARALAMPIDIS, K, TROJANOWSKA, M., OSBOURN, A.E., Biosynthesis of triterpenoid saponins in plants, Adv. Biochem. Eng., in press. 

Ginsenosides are triterpenoid saponins found nearly exclusively in ginseng and they have been the target of a lot of research as they are believed to be the main active principles behind the claims of ginsengs efficacy. Ginseng refers to species within the genus Panax (Araliaceae... 

Plohmann, B., Bader, G., Hiller, K., and Pranz, G. (1997). Immunomodulatory and anti-tumoral effects of triterpenoid saponins. Pharmazie 52, 953-957. 

Astragaloside IV (76) and astragaloside I (77) are the two active cycloar-tane-type major triterpenoid saponins isolated from Astragalus mem-branaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao or A. membranaceus (Fisch.) Bge., were evaluated to exhibit protective effects on the early stage... 

CS022 Lu, Y., T. Umeda, A. Yagi, K. Sakata, T. Chaudhuri, D. K. Ganguly and S. Sarma. Triterpenoid saponins from the roots of tea plant (Camellia sinensis var. assamica). Phytochemistry 2000 53(8) 941-946. 

Yayli, N. Findlay, J.A. (1999) A triterpenoid saponin from Cucumaria frondosa. Phytochemistry, 50, 135-8. 

Shaker, K.H. et al., A new triterpenoid saponin from Ononis spinosa and two new flavonoid glycosides from Ononis vaginalis, Z. Naturforsch. B, 59, 124, 2004. 

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