Enantioselective Total Synthesis of (+)-Gelsemine: Determination of Its Absolute Configuration

The unique hexacyclic cagelike structure of (+)-gelsemine (1) has been accomplished. The first enantioselective total synthesis of this alkaloid features a facile construction of the bicyclo[3.2.1] core by means of two rearrangement reactions and the efficient formation of the pyrrolidine ring by an intramolecular Michael addition. Bn=Benzyl.