| Autor: |
Nyamboki DK; Department of Chemistry, Faculty of Sciences, Egerton University, P.O. Box 536, 20115 Egerton, Kenya.; Institute of Environmental Research (INFU), Department of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Straße 6, 44227 Dortmund, Germany., Bedane KG; Department of Chemistry, Addis Ababa University, P.O. Box 33658, 1230 Addis Ababa, Ethiopia., Hassan K; Department of Microbial Drugs, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany., Brieger L; Inorganic Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Straße 6, 44227 Dortmund, Germany., Strohmann C; Inorganic Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Straße 6, 44227 Dortmund, Germany., Spiteller M; Institute of Environmental Research (INFU), Department of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Straße 6, 44227 Dortmund, Germany., Matasyoh JC; Department of Chemistry, Faculty of Sciences, Egerton University, P.O. Box 536, 20115 Egerton, Kenya. |
| Abstrakt: |
Three new bufadienolides, namely, paulliniogenin A ( 1 ), paulliniogenin B ( 2 ), and 16β-formyloxybersamagenin 1,3,5-orthoacetate ( 3 ), together with two known bufadienolides and six known phenolic substances, were isolated from the stem bark of Bersama abyssinica subsp. abyssinica and B. abyssinica subsp. paullinioides . The structures of the compounds were elucidated based on their NMR and HRMS data analyses. The relative configurations were defined by single-crystal X-ray crystallography and NOESY correlations. Cytotoxicity against the L929 and KB3.1 cancer cell lines of the isolated compounds was investigated using an MTT assay. Paulliniogenin A ( 1 ) and 16β-hydroxybersamagenin-1,3,5-orthoacetate ( 4 ) showed cytotoxicity against the KB3.1 cell line with IC 50 values of 1.4 ± 0.77 and 1.6 ± 0.81 μM, respectively. Moreover, paulliniogenin A ( 1 ) and paulliniogenin B ( 2 ) demonstrated weak activity against Staphylococcus aureus . |
