Total Synthesis of Pestalotioprolide E and Structural Revision of Pestalotioprolide F
作者:Debobrata Paul、Sanu Saha、Rajib Kumar Goswami
DOI:10.1021/acs.orglett.8b01894
日期:2018.8.3
A short and convergent strategy for the first asymmetric total synthesis of cytotoxic macrolides pestalotioprolides E and F has been developed. The key features of this synthesis include Takai olefination, Sonogashira coupling, Ni-assisted partial hydrogenation of alkyne, modified Steglich reaction to generate the ester moiety, and intramolecular Horner–Wadsworth–Emmons (HWE) olefination to complete
The absolute configuration at C-17, the carbon bearing the distal hydroxy group of the 14-membered natural product gliomasolide D, was assigned as R by comparison of 13C NMR shifts and specific rotation values of the epimers at C-17. The first total synthesis of gliomasolide D along with its C-17 epimer, regioselective macrocyclization (18 membered vs 14 membered), and regioselective Wacker oxidation
通过比较13 C NMR位移和差向异构体在C-17处的比旋光度,将C 14处的绝对构型(带有14元天然产物胶质瘤固体D的远端羟基的碳)指定为R。胶质瘤固体D及其C-17差向异构体的首次全合成,区域选择性大环化(18元对14元)和区域选择性Wacker氧化是本研究的重点。