作者:Laëtitia Chausset-Boissarie、Roman Àrvai、Graham R. Cumming、Laure Guénée、E. Peter Kündig
DOI:10.1039/c2ob25880c
日期:——
The total syntheses of the Lythracea alkaloids (+)-vertine and (+)-lythrine are described. Enantioenriched pelletierine is used as a chiral building block and engaged into a two step pelletierine condensation leading to two quinolizidin-2-one diastereomers in a 8 : 1 ratio. The major product is used in the synthesis of (+)-vertine via aryl–aryl coupling and ring closing metathesis to provide a Z-alkene α to the lactone carbonyl function. The same procedure was used for (+)-lythrine after base induced epimerization of the main quinolizidin-2-one diastereomer. Alternative classical ring closure strategies like macrolactonisation or aryl–aryl coupling failed.
描述了(+)-vertine和(+)-lythrine这两种Lythracea生物碱的全合成过程。使用对映富集的pelletierine作为手性构建块,并通过两步pelletierine缩合反应,以8:1的比例生成两种喹啉环己二酮二异构体。主要产物通过芳基-芳基偶联和环闭合复分解反应合成(+)-vertine,提供了与内酯羰基功能团α位的Z-烯烃。对主要喹啉环己二酮二异构体进行碱诱导的异构化后,采用相同步骤合成了(+)-lythrine。传统的环闭合策略,如大环内酯化或芳基-芳基偶联都未能成功。