A seven-step synthesis of the 1-methyl-3-(o-azidophenyl)quinolin-2-one, a c
ommon intermediate for the synthesis of the cryptotackieine and cryptosangu
inolentine alkaloids, is described. This intermediate is directly converted
into cryptotackieine 1 by an intramolecular aza-Wittig reaction with trime
thylphosphine; alternatively heating followed by reduction of the resulting
indoloquinoline derivative provided cryptosanguinolentine 2. (C) 1999 Else
vier Science Ltd. All rights reserved.