General methods of alkaloid synthesis. A new approach to the synthesis of the 5,10b-ethanophenanthridine Amaryllidaceae alkaloids. The total synthesis of (±)-3-epi-elwesine
Abstract
Methyl vinyl ketone annelation of the Δ2- pyrroline (5b) prepared by acid-catalysed thermal rearrangement of the cyclopropyl imine (7) has been exploited in an efficient eight-step stereoselective total synthesis of racemic 3-epi-elwesine (3b).