Non-destructive structural analysis
of triterpen and steroid glycosides
by 2D NMR
A.S. Shashkov, V. V. Kachala





    Triterpene glycosides, also known as  saponines, represent one of numerous class of natural compounds. They  serve as secondary metabolites of mixed biosynthesis, like alkaloids, flavonoids, oligosaccharides etc.).
    Growing interest to natural saponines caused as by scientific aspects of extraction and structural analysis of these compound, as by the fact of their wide spectrum of biological activities, like bacteriñidal, fungicidal, antvirial, cytotoxic, anticancer, ichtiotoxic, spermicidal, cardiovsicular, analhetic, antiallergic and many others.
    Saponines are glycosides of tpiterpenoids, which form one of the most numerous group of natural terpenoids. The main groups of triterpenoids and their glycosides represented by tetracyclic derivatives of lanostane 1, cycloartane 2, dammarane 3, eufane 4, and pentacyclic derivatives of ursane (alpha-amirine) 5 , lanostane (beta-amirine) 6, lupane 7, and hopane 8. (Pic.1)
Pic1. Triterpenes

There are many methods for determination of the structure of glycosides, such as chemical analysis, IR, UV, and NMR spectroscopy, mass-spectrometry and X-ray structure analysis. But most suitable method is NMR as non-destructive and informative one. We developed  reserach scheme for triterpene glycosides which allows us make complete distrubutions of peaks both in 1H NMR and 13C NMR spectra (Pic. 2)
 
Pic.2 Research scheme


Under construction
Updated 18.10.2000