Joziknipholones A and B: The first axially chiral dimeric phenylanthraquinones from the roots of Bulbine frutescen
Date
2006Author
G, Bringmann
J, Mutanyatta
K, Maksimenka
R, Brun
G, Peter M
M, Heydenreich
O, Midiwo J
M, Wanjohi J
A, Yenesew
Type
ArticleLanguage
enMetadata
Show full item recordAbstract
From the roots of the African plant Bulbine frutescens (Asphodelaceae), two unprecedented novel dimeric phenylanthraquinones, named joziknipholones A and B, possessing axial and centrochirality, were isolated, together with six known compounds. Structural elucidation of the new metabolites was achieved by spectroscopic and chiroptical methods, by reductive cleavage of the central bond between the monomeric phenylanthraquinone and -anthrone portions with sodium dithionite, and by quantum chemical CD calculations. Based on the recently revised absolute axial configuration of the parent phenylanthraquinones, knipholone and knipholone anthrone, the new dimers were attributed to possess the P-configuration (i.e., with the acetyl portions below the anthraquinone plane) at both axes in the case of joziknipholone A, whereas in joziknipholone B, the knipholone part was found to be M-configured. Joziknipholones A and B are active against the chloroquine resistant strain K1 of the malaria pathogen, Plasmodium falciparum, and show moderate activity against murine leukemic lymphoma L5178y cells.
URI
http://profiles.uonbi.ac.ke/jwanjohi/publications/yenesew-wanjohi-j-m-midiwo-j-o-heydenreich-m-peter-m-g-brun-r-maksimenka-k-muthttp://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/28123
http://onlinelibrary.wiley.com/doi/10.1002/chem.200701328/abstract
Citation
Yenesew, A. Wanjohi, J. M., Midiwo, J. O., Heydenreich, M. Peter, M. G., Brun, R., Maksimenka, K., Mutanyatta, J., and Bringmann, G. (2006). Joziknipholones A and B: The first axially chiral dimeric phenylanthraquinones from the roots of Bulbine frutescen, MURABA, DR. WANJOHI JOHN , Bulbine frutescens, (2006) copy at http://profiles.uonbi.ac.ke/jwanjohi/publications/yenesew-wanjohi-j-m-midiwo-j-o-heydenreich-m-peter-m-g-brun-r-maksimenka-k-mutPublisher
Department of Chemistry