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Updated: May 4, 2026

A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
The chemical and biological potential of C ring modified triterpenoids
Bianka Siewert1, Jana Wiemann1, Alexander Köwitsch1
1Bereich Organische Chemie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, D-06120 Halle, Saale, Germany.
Abstract:
A convenient and elegant route has been developed to separate the natural regioisomers triterpenoids ursolic acid (UA) and oleanolic acid (OA) as well as derivatives thereof. Eleven unknown derivatives of OA were designed, synthesized, and their cytotoxicity was investigated. Further sixteen compounds were prepared to correlate all compounds in a SAR study. It could be shown that C-ring modifications of OA and UA have only a moderate influence onto the cytotoxic activity of the compounds but a significant impact onto the ability to trigger apoptosis in ovarian cancer cells (cell line A2780).
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