Total Synthesis Of Alkaloid(±)-205B C-5a Isomer

Alkaloid(-)-205 B is a natural product of Alkaloid,which has attracted a lot of organic synthesizers due to its complex structure and potential biological activity.In this paper,Alkaloid(-)-205 B C-5a isomer are used as our research target,and designed a unique and novel total synthesis route.This paper is divided into the following three chapters:The first chapter summarizes the natural products,and briefly analyzes the purpose,significance and related research status at home and abroad.The second chapter introduces the total synthesis of Alkaloid(-)-205 B C-5a isomer.Starting from the retrosynthetic design,we explain the simple,reasonable and efficient synthesis route based on the retrosynthetic design.In the synthesis route of Alkaloid(-)-205 B C-5a isomer designed in this paper,the key two steps asymmetric Michael addition reaction was used to complete the construction of intermediate of tetra-piperidine and tricyclic system respectively.In the final we completed the total synthesis of Alkaloid(-)-205 B C-5a isomer.And the products were characterized by NMR.This entire route is simple and efficient.The third chapter summarizes the specific content of the route design,including the specific experimental steps and conditions,the yield of each step and the spectra data of the compound.