钙化固醇3的总合成无需使用光化学方法即可完成。9α-Chloro- des- AB -cholestan-8-one {5α-chloro-1β-[(1 R)-1,5-methyldimethylhexyl]-7aβ-methyl- trans - perhydroindan -4-one}(1; X =将(α-Cl)和(1 S)-3-乙炔基-4-甲基环己-3-烯-1-醇(2; R = H)合并得到氯醇(3; X =α-Cl),首先转化为二烯炔(4),然后通过乙炔键的半氢化反应转化为前钙化甾醇3(5)。描述了与维生素原和相关途径有关的模型实验。
Investigating Direct Access to 2-Oxospiro[4.5]decanones via 6π-Electrocyclisation
作者:Rebecca H. Pouwer、Heiko Schill、Craig M. Williams、Paul V. Bernhardt
DOI:10.1002/ejoc.200700367
日期:2007.10
The 2-oxospiro[4.5]decan-1-one (or spiro-γ-lactone) structural motif is contained within a number of natural products, for example, the clerodane family of diterpenes. Methods to construct this structural motif are somewhat limited and usually involve multiple functional group interconversions. A novel synthetic approach to this system utilising 6π-electrocyclisation has been identified and associated