Astragalus sapogenins

During the almost 20-years of research on Astragalus sapogenins and saponins, more than 40 species firom this genus have been studied and above 40 triterpenoid sapogenins and up to 130 saponins have been isolated and identified until now, and for some of them the biological activity has also been studied. 

Table (1) and Table (2), listed in alphabetic order, include the triterpenoid sapogenins and their glycosides (saponins), respectively, extracted fi om Astragalus spp., their structures and plant sources, covering a literature up to the beginning of2000. [146,147,219]... 

Structure determination of sapogenins and saponins from genus Astragalus originally involves a combination of chromatographic, chemical and spectral methods nuclear magnetic resonance spectroscopy (NMR) with chemical transformation and enzymatic degradation, as well as MS (mass spectroscopy). 

The side chain m. Astragalus cycloartane sapogenins and saponins may be of different type (Table 1) side chain with acyclic construction, or with tetrahydrofuranic ring at C-17 (20,24-epoxy cycloartane, the most rapresentative side chain as in cycloastragenol, 18), or with a tetrahydropyranic ring (20,25-epoxy and 16,23-epoxy cycloartane derivatives) and with two condenced epoxy ring (16P,23 16a,24-diepoxycycloartane compounds). All these chains influence the signals of the carbons and protons involved and that of the vicinal atoms [147,219]. 

---