Synthesis and cytotoxic screening of beta-boswellic acid derivatives


  • Ratna Kancana Wolfram Martin-Luther Universität Halle-Wittenberg
  • Anja Barthel-Niesen Martin-Luther Universität Halle-Wittenberg
  • Renate Schäfer Martin-Luther Universität Halle-Wittenberg
  • Lucie Heller Martin-Luther Universität Halle-Wittenberg
  • Ahmed Al-Harrasi University of Nizwa
  • René Csuk Martin-Luther Universität Halle-Wittenberg



Beta-boswellic acids are triterpenoids being generic to the plants of genus boswellia. Although they were shown to exhibit different biological activities, the cytotoxic potential of b-boswellic acid derivatives remained by and large unexploited. To expand the potential of these compounds we developed simple procedures for the interconversion of the most important b-boswellic acids 1-4 and prepared several other derivatives 5-48. These compounds were screened for their cytotoxic activity in sulforhodamine B assays employing several human tumor cell lines and nonmalignant mouse fibroblasts. One of these compounds, a difluoromethylester of 3-O-acetyl-11-keto-beta-boswellic acid 23, was cytotoxic for human breast adenocarcinoma cells MCF-7 (EC50 = 6.5 mM) while being significantly less cytotoxic for the mouse fibroblasts.

Author Biographies

Ratna Kancana Wolfram, Martin-Luther Universität Halle-Wittenberg

Organic Chemistry

Anja Barthel-Niesen, Martin-Luther Universität Halle-Wittenberg

Organic Chemistry

Renate Schäfer, Martin-Luther Universität Halle-Wittenberg

Organic Chemistry

Lucie Heller, Martin-Luther Universität Halle-Wittenberg

Organic Chemistry

Ahmed Al-Harrasi, University of Nizwa

Chair of Oman's Medicinal Plants and Marine Natural Products

René Csuk, Martin-Luther Universität Halle-Wittenberg

Organic ChemistryHead of Department


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Medicinal Chemistry