A New Approach to the Total Synthesıs of (±)-Nordasycarpıdone by Rıng-closure wıth Tetrachloro-1,4-benzoquınone

Abstract

A new synthetic route for the (±)-nordasycarpidone was achieved in five steps with an overall yield of 41%. This route involves ring closure and formation of 5 which has a methanoazocino[4,3-b]indole skeleton in the key step. The reaction also involved a cyclization reaction of tetrahydrocarbazole with a monoalkyl nitrile side chain at the C-2 position, and this reaction was mediated by tetrachloro-1,4-benzoquinone (TCB). The central step in the synthesis was the closure of the D-ring of the intra-molecular structure and the addition of amine, which resulted in an aza-tetracyclic substructure that contained the ABCD-ring of the strychnos alkaloid family.