Studies Toward Total Synthesis Of Palhinine A,Strychnochromine And Goniomine

This dissertation describes recent development of the synthetic approaches to access of natural products with medium-sized rings as well as synthetic studies toward Lycopodium alkaloid palhinine A and Indole alkaloids strychnochromine and goniomine was provided.Chapter 1.Advances of the construction of medium-sized rings and their applications in natural products synthesis(review)A brief introduction of the construction methods of high-strained medium-sized rings is described,thereafter,applications of these methods in natural products synthesis in recent years are selectively provided by classification based on the reaction types.Chapter 2.Synthetic studies toward Lycopodium alkaloid palhinine AA brief introduction of the isolation,structure characteristics and former synthetic efforts of Lycopodium alkaloid palhinine A is given.And an efficient approach for the synthesis of 9/6/6 tricyclic structure of Lycopodium alkaloid palhinine A has been proposed and accomplished.The developed synthetic route,featureing oxidative dearomatization and tandem hydroxyl oxidation/intramolecular Diels-Alder(IMDA)reactions to assemble the A/C/D tricyclic ring system,realized the construction of the highly strained nine-membered azonane ring of palhinines.Chapter 3.Biosynthetic studies toward Indole alkaloid strychnochromine and goniomineA brief introduction of the isolation and biosynthetic hypothesis of Indole alkaloids strychnochromine and goniomine is provided.And then we proposed a synthetic pathway features Michael addition and Mitsunobu reaction toward these two Indole alkaloids through the completion of stemmadenine alkaloid.