Document Type
Article (Restricted)
Publication Date
1-1-2010
Abstract
A total of 25 alkaloids were isolated from the leaf and stem-bark extracts of Alstonia spatulata, of which five are new alkaloids of the strychnan type (alstolucines A-E, 1-5)and the other, a new alkaloid of the secoangustilobine A type(alstolobine A, 6). The structures of these alkaloids were established using NMR and MS analysis and, in the case of alstolucine B (2), also confirmed by X-ray diffraction analysis. A reinvestigation of the stereochemical assignment of scholaricine (13) by NMR and X-ray analyses indicated that the configuration at C-20 required revision. Alkaloids 1, 2, 6, 7, 9, 10, and 13 reversed multidrug resistance in vincristine-resistant KB cells.
Keywords
Alkaloids, NMR, Alstonia spatulata, Alstolucine.
Divisions
CHEMISTRY
Publication Title
Journal of Natural Products
Volume
73
Publisher
American Chemical Society and American Society of Pharmacognosy
Additional Information
Department of Chemistry, University of Malaya --- doi: 10.1021/np100552b