Inventors:
Martin E. Kuehne - Burlington VT
Assignee:
University of Vermont - Burlington VT
International Classification:
C07D48716
Abstract:
The invention relates to the preparation of vincadifformine. Tetrahydro-. beta. -carboline (II) is reacted with benzoyl chloride to provide 2-benzoyl-1,2,3,4-tetrahydro-9H-pyrido-[3,4b]-indole (III). Then compound (III) is reduced to give 2-benzyl-1,2,3,4-tetrahydro-9H-pyrido[3,4b]-indole (IV). Thereafter, compound (IV) is transformed by t-butyl hypochlorite into chloroindolenine derivative (V) which is immediately treated with thallium t-butyl methyl malonate to give t-butyl methyl 3-benzyl-1,2,3,4,5,6-hexahydroazepino-[4,5b]-indole-5,5-dicarboxylate (VI). Compound (VI) is then partly decarboxylated into methyl 3-benzyl-1,2,3,4,5,6-hexahydroazepino-[4,5b]-indole-5-carboxylate (VII). Compound (VII) is hydrogenated to give methyl 1,2,3,4,5,6-hexahydroazepino-[4,5b]-indole-5-carboxylate (IX). In an alternative embodiment, compound (VI) can be hydrogenated to methyl t-butyl 1,2,3,4,5,6-hexahydroazepino-[4,5b]-indole-5,5-dicarboxylate (VIII) which is then decarboxylated into compound (IX).