Synthesis of ajmalicine derivatives using Wittig-Horner and Knoevenagel reactions

Article abstract of DOI:10.1016/S0040-4039(99)01921-8

2-(2,3,4,9-Tetrahydro-1H-β-carbolin-1-yl)acetaldehyde, synthesized from tryptamine in five steps, is easily homologated by Wittig-Horner or Knoevenagel reactions to substituted acrylates. These highly reactive compounds are key intermediates in the synthesis of analogs of the natural indol alkaloid ajmalicine.