A Systematic NMR Approach for the Determination of the Molecular Structure of Steroidal Saponins

  • Pawan K. Agrawal
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 405)


Steroidal saponins and their aglycones (steroidal sapogenins), which are widely distributed in various plant families, are attracting the attention of research workers not only as economically important raw material convertible into various steroid hormonal drugs, but recently also as biologically active materials having independent value.1–6 All steroidal sapogenins possess a parent cholestane carbon skeleton (C27), having perhydrocyclopentenophenanthrene nucleus (rings A, B, C, and D), the side chain of which undergoes cyclization resulting in either a hexacyclic system (four carbocyclic and two heterocyclic rings) or a pentacyclic system (four carbocyclic and one heterocyclic ring). Most of these contain, in addition, one 5-membered ring (E) and one 6- or 5-membered ring (F), both of which are heterocyclic and fixed in a spiran fashion at C-22. Those cholestane derivatives which are formed by the ring opening of both heterocyclic rings are also included in this class because these have been regarded as intermediate in the biosynthesis of steroidal sapogenins.7–9


Steroidal Saponin Monosaccharide Residue Olefinic Bond Anomeric Configuration Chemical Shift Range 
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Copyright information

© Plenum Press, New York 1996

Authors and Affiliations

  • Pawan K. Agrawal
    • 1
  1. 1.Central Institute of Medicinal and Aromatic PlantsLucknowIndia

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