Studies towards asymmetric total synthesis of bioactive natural product via regioselective Fischer indolization: (-)-tabersonine

Abstract

Recently we have demonstrated that ene-hydrazide is readily available from enol triflate in regiochemically defined form, which may undergo Fischer indolization reaction with no regiochemical scrambling. In order to prove its usefulness, we then started to apply our new method to the synthesis of various aspidosperma alkaloids. Prior to syntheses of a variety of intricate aspidosperma alkaloids, we initiated synthesis of (-)-tabersonine. Regioselective Fischer indolization under Lewis acid condition led us to be close to the total synthesis of (-)-tabersonine. Presented herein are the results so far of total synthesis of (-)-tabersonine.