Studies On The Synthesis Of (±)-Kopsihainanine A, (±)-Aspidospermidine And Calycilactone A

The thesis aims at the synthetic studies toward total syntheses of (±)-Kopsihainanine A,(±)-Aspidospermidine and Calycilactone A. It consists of the following four parts:Chapter 1. The use of Claisen rearrangement in the organic synthesis in recent five years(review)Introduce the synthetic method of Claisen rearrangement and their applications in organic synthesis, especially the synthesis of natural products in recent five years (2009-2013), besides,their advantages and limitations are compared.Chapter 2. Total Synthesis of Kopsihainanine AConcise separation and the activity of Kopsihainanine A are introduced. The first total synthesis of Kopsihainanine A has been achieved in 10 steps with 12% overall yield from the commercial available 1,2,3,9-tetrahydro-4H-carbazol-4-one, featured with an intramolecular conjugate addition of the iminium ion formed in situ with amide and a substrate controlled diastereoselective a-hydroxylation.Chapter 3. Total Synthesis of (±)-AspidospermidineThe total synthesis of (±)-Aspidospermidine has been acomplished in 10 steps with 14%overall yield from the commercial available 1,2,3,9-tetrahydro-4H-carbazol-4-one, exploiting an intramolecular conjugate addition of the iminium ion formed in situ with amide as the key step.Chapter 4. Study on Synthesis of Calycilactone AThe synthetic studies towards the ECD rings of Calycilactone A have been performed. Two five-member ring segments of Calycilactone A have been achived, and they are connected with ester.