Studies On The Biomimetic Total Synthesis Of Valjatrate E

Valjatrate E is a natural product isolated from the rhizome of the traditional Chinese medicine Valeriana jatamansi Jones.Structurally,Valjatrate E bears a cis-fused cyclopentane and dihydropyran skeleton with three adjacent chiral centers.Valjatrate E has attracted great attention due to its anti-anxiety activity.To date,the main sours of Valjatrate E mainly include extraction and isolation,which greatly limits its application in pharmaceutical chemistry.The effective synthesis of Valjatrate E skeleton by using available starting material under mild reaction condition was proposed base on the biomimetic synthesis,which could provide helpful instruction in the total synthesis of Valjatrate EIn the first chapter,we briefly summarized the structure,classification and physiological activities of iridoids.We focused on the separation and extraction,structural characteristics and biological activity of Valjatrate E;we systematically summarized the research progress of monoterpene iridoids based on different synthetic target products in recent years(Scheme 1)In the second chapter,we concentrated on the biomimetic synthesis of neonepetalactone.In the first part,we introduced the basic concepts of biomimetic synthesis and the biosynthesis pathway of monoterpenoids.In the second part,we summarized the total synthesis of neonepetalactone;Both formic acid and 5-Deazaflavins could be used as cyclization reagents to synthesize the neonepetalactone(Scheme 2).In the third chapter,we concentrated on the biomimetic synthesis of Valjatrate E.In the first part,we introduced the biosynthesis pathway of iridoids.In the second part,Nmethylaniline were used as cyclization reagents to synthesize the Valjatrate E skeleton(Scheme 3).In this paper,we synthesis the core structure of Valjatrate E base on biomimetric synthesis.