1.

Cytotoxicity of Secondary Metabolites from Dracaena viridiflora Engl & Krause and their Semisynthetic Analogues

Rémy Bertrand Teponno, Jean Paul Dzoyem, Raymond Ngansop Nono, Ulrich Kauhl, Louis P. Sandjo, Léon Azefack Tapondjou, Udo Bakowsky and Till Opatz

Department of Chemistry, Faculty of Science, University of Dschang, Box 67, Dschang, Cameroon

Johannes Gutenberg University Mainz, Institute of Organic Chemistry, Duesbergweg 10–14, D-55128 Mainz, Germany

Department of Biochemistry, Faculty of Science, University of Dschang, Box 67, Dschang, Cameroon

Department of Pharmaceutics and Biopharmaceutics, Philipps University of Marburg, Robert-Koch-Str.4, D-35037 Marburg, Germany

Abstract: The MeOH extract of Dracaena viridiflora was found to display significant cytotoxicity against some cancer cell lines. Systematic phytochemical investigation of this extract led to the isolation and structure elucidation of ten secondary metabolites including five spirostane (1-5) and one furostane (6) steroidal saponins. Furthermore, some acetylated spirostane analogues and three previously unreported derivatives with the 22,26-epoxycholesta-5,22-diene skeleton (15-17) were prepared from trillin (1), prosapogenin A of dioscin (2) and dioscin (4) by reaction with ZnCl 2/Ac 2O. Among the isolated and semisynthetic compounds, dioscin showed the most potent cytotoxicity against A549, Jurkat and Skov-3 cells with IC 50 values of 0.42, 1.70 and 1.90 µg/mL, respectively. It was noteworthy that acetylation of the bioactive compounds led to semisynthetic derivatives which unfortunately did not present any activity. This is the first report on the phytochemical and pharmacological investigation of Dracaena viridiflora.

Keywords: Dracaena viridiflora ; steroidal saponins;epoxycholesta-5,22-dienes; cytotoxicity. © 2017 ACG Publications. All rights reserved.