Total Synthesis Of Lycopodium Alkaloids (-)-8-Deoxyserratinine

Lycopodium alkaloids are isolated from the pteridophyta lycopodium and related plants with similar biogenesis. These compounds present in lycopodium and related species, especially plants of Huperziaceae and Lycopodiaceae. The Lycopodium alkaloids often possess unusual skeletons and promising bioactivity, which attract the attention of numerous organic chemists and medicinal chemists. In 1986, Jiasen-Liu, a Chinese scientist, isolated Huperzine A from Huperzia serrata, a traditional Chinese medicine. Huperzine A has been shown to be a potent, reversible inhibitor of acetylcholine esterase and significantly impacts the investigate of Lycopodium alkaloids. Owing to their appealing biological activities as well as synthetically challenging polycyclic systems, a number of total syntheses of Lycopodium alkaloids have been conducted and documented in the literature.This thesis describes the synthetic studies on Lycopodium alkaloids of fawcettimine class, the first asymmetric total synthesis of (-)-8-Deoxyserratinine was successfully realized and summarized in this thesis.Three chapters are included in this thesis. In the first chapter, we summarized the synthesis of fawcettimine class alkaloids, including fawcettimine,sieboldine A,paniculate,Magellanine and magellaninone.In chapter 2, studies towards the first asymmetric total synthesis of (-)-8-Deoxyserratinine was described. We completed the first enantioselective total synthesis of (-)-8-Deoxyserratinine in 15 steps from enone (-)-187 with 7% overall yield. The key features include a highly efficient Helquist annulation to furnish the cis-fused 6/5 bicycle, construction of the aza nine-membered ring system employing double N-alkylation strategy and asymmetric Shi epoxidation to secure the desiredβ-epoxide stereospecifically.Experiment procedure, physical and spectrum data for compounds described in Chapter 2 are recorded in Chapter 3.