Study on the Total Synthesis of Et 743 and its Analogues: Synthesis of a Tricyclic Intermediate and its 11-Epimer  

作　　者：Ye Feng TANG, Zhan Zhu LIU, Shi Zhi CHENInstitute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union MedicalCollege, Beijing 100050 

出　　处：《Chinese Chemical Letters》2003年第10期996-998,共3页中国化学快报（英文版）

摘　　要：The tricyclic compound 1, a key intermediate of the pentacyclic core of Et 743 and its analogues, was synthesized. Its 11-epimer was found as the product of racemization when BOP was used as the coupling agent, but not when BOP-C1 used in the same reaction. The stereochemistry of both isomers was confirmed on basis of the 1H NMR and NOE-difference spectra.The tricyclic compound 1, a key intermediate of the pentacyclic core of Et 743 and its analogues, was synthesized. Its 11-epimer was found as the product of racemization when BOP was used as the coupling agent, but not when BOP-C1 used in the same reaction. The stereochemistry of both isomers was confirmed on basis of the 1H NMR and NOE-difference spectra.

关 键 词：Et 743 tricyclic compound synthesis stereochemistry. 

分 类 号：O624[理学—有机化学]