Studies on Taxadiene Synthase: Interception of the Cyclization Cascade at the Isocembrene Stage with GGPP Analogues
作者:Siew Yin Chow、Howard J. Williams、Qiulong Huang、Samik Nanda、A. Ian Scott
DOI:10.1021/jo0517489
日期:2005.11.1
analogue was transformed by taxadiene synthase in vitro to hydrocarbon products in varying yields, and the structures of the major product in each reaction were solved by GCEIMS and one- and two-dimensional (1H and 13C) NMR and found to be 14-membered monocyclic isocembrenyl diterpenes, indicating that the first C−C bond formation catalyzed by taxadiene synthase could be uncoupled from the other subsequent
已经建议由紫杉二烯合酶催化的GGPP向紫杉二烯的环化通过一系列单环异辛烯基和双环黄连基-碳环化中间阶段进行。一组GGPP类似物与废除或在Δ扰动π-亲核10双键(GGPP编号)合成,并在单阶段与紫杉二烯合酶孵育以截距环化级联。紫杉二烯合酶在体外将每个类似物以不同的产率转化为烃产物,并且每个反应中主要产物的结构均通过GCEIMS以及一维和二维(1 H和13C)NMR,发现是14元单环异辛烯基二萜,表明通过使用适当设计的底物类似物,由紫杉二烯合酶催化的第一个C-C键形成可与其他后续键形成事件脱钩。使用紫杉二烯合酶形成和分离这些异异戊烯基二萜产物支持了异异戊烯基阳离子是GGPP环合到紫杉二烯的中间体的提议。