structure of the novel pentacyclic indole, danuphylline, from Kopsia dasyrachis was established by spectral analysis. Anodic oxidation of the hexacylic alkaloid methyl 11,12-methylenedioxychanofruticosinate on platinum in TEAP/MeCN-CH2Cl2 (2 F mol(-1)) yielded an iminium ion salt which on silica gel chromatography underwent a facile retro-aldol process to give danuphylline. Allowing the oxidation to proceed until consumption of 4 F mol(-1) of charge resulted in an unprecedented electrochemically-mediated aromatic chlorination yielding 10-chloro-danuphylline. (C) 1999 Elsevier Science Ltd. All rights reserved.