Bartels Florian, Hong Young J, Ueda Daijiro, Weber Manuela, Sato Tsutomu, Tantillo Dean J, Christmann Mathias
Institute of Chemistry and Biochemistry , Freie Universität Berlin , Takustraße 3 , 14195 Berlin , Germany . Email:
Department of Chemistry , University of California-Davis , Davis , California 95616 , USA . Email:
Chem Sci. 2017 Dec 1;8(12):8285-8290. doi: 10.1039/c7sc03903d. Epub 2017 Oct 16.
The first chemical synthesis of pentacyclic onocerane triterpenoids has been achieved. A putative biomimetic tricyclization cascade is employed to forge a fused decalin-/oxepane ring system. The synthetic route proceeds to (+)-cupacinoxepin in seven steps and to (+)-onoceranoxide in eight steps in the longest linear sequence, when starting from geranyl chloride and (+)-sclareolide. The bioinspired epoxypolyene cyclization is supported by computational and enzymatic studies.
五环奥诺烷三萜类化合物的首次化学合成已经实现。采用一种假定的仿生三环化串联反应来构建稠合的十氢化萘-/氧杂环庚烷环系。从香叶基氯和(+)-香紫苏内酯开始，合成路线在最长线性序列中七步合成(+)-杯苋草氧杂环庚烷，八步合成(+)-奥诺烷氧化物。计算和酶学研究支持了这种受生物启发的环氧多烯环化反应。
