Fluorinated and rearranged gedunin derivatives

When treated with (diethylamino) sulfur trifluoride (DAST), 11 alpha-hydroxygedunin gave 11 beta-fluorogedunin and 9,11-didehydrogedunin, whereas deacetylgedunin afforded two skeletal rearranged products 6 and 7, in which the Me-30 had shifted from position 8 to position 7. Of those products, 11 beta-fluorogedunin and 6 were shown to be more cytotoxic than gedunin on P-388 leukemia cells. (C) 2012 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.