A new approach to the total synthesis of (±)-nordasycarpidone by ring-closure with tetrachloro-1,4-benzoquinone

Abstract

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-molecu-lar structure and the addition of amine, which resulted in an aza-tetracyclic substructure that contained the ABCD-ring of the strychnos alkaloid family. © 2020, Macedonian Journal of Chemistry and Chemical Engineering.