A totalsynthesis of (+)-aspidospermidine (1) is described. The key reactions used in the synthesis of this pentacyclic Aspidospermaalkaloid were a deracemizing imine alkylation/Robinson annulation sequence, a selective “redox ketalization”, and an intramolecular Schmidt reaction. A Fischer indolization step carried out on a tricyclic ketone mirrored the sequence reported by Stork and Dolfini in their
Regiocontrol in an Intramolecular Schmidt Reaction: Total Synthesis of (+)-Aspidospermidine
作者:Rajesh Iyengar、Klaas Schildknegt、Jeffrey Aubé
DOI:10.1021/ol005913c
日期:2000.6.1
[reaction--see text] A total synthesis of (+)-aspidospermidine (1) is described, featuring an intramolecular Schmidt reaction as the key step. The effects of stereochemistry and protectinggroup status on the regio- and chemoselectivity of this reaction were examined.