Total synthesis of the Strychnos alkaloid tubotaiwine

Abstract
The total synthesis of racemic tubotaiwine 8 has been achieved from the tetracyclic intermediate 1, the key steps being the construction of the C(7)-quaternary centre by cyclization of a thionium ion upon the indole 3-position and the introduction of the C(16)-methoxycarbonyl substituent by photochemical rearrangement of the N-methoxycarbonylenamine 7.