Serratezomine A 是一种结构多样的化合物,被称为石松生物碱。本文描述了锯雷佐明 A 的关键支持研究和成功的全合成。该合成的显着特征包括首次在全合成中应用自由基介导的乙烯基胺化和 Hwu 氧化烯丙基化,以及通过跨环 S N i 反应进行分子内内酯化。从战略角度来看,保护基团的最少使用以及使用umpolung烯丙基化高度非对映选择性形成受阻四元立构中心也是亮点。通过逆曼尼希/曼尼希序列观察季碳差向异构化,凸显了沙雷佐明 A 中 C8 处的轴向醇带来的额外挑战。
Use of the <i>V</i><i>icinal</i> Element Effect for Regiochemical Control of Quinone Substitutions and Its Implication for Convergent Mitomycin Construction
作者:Amie L. Cox、Jeffrey N. Johnston
DOI:10.1021/ol016625z
日期:2001.11.1
[GRAPHICS]Nucleophilic substitution reactions of 2-methoxy-3-alkyl-p-benzoquinones are described as they relate to the construction of the mitomycin backbone. Normally controlled by activating groups attached to the olefin, the observed regioselection in these cases is determined by the deactivating substituent. Approximation of carbonyl activating ability would not have predicted the behavior of two systems investigated in which the poorer of two leaving groups is substituted in each case.
Free Radical-Mediated Vinyl Amination: Access to <i>N,N</i>-Dialkyl Enamines and Their β-Stannyl and β-Thio Derivatives
作者:Erode N. Prabhakaran、Benjamin M. Nugent、Amie L. Williams、Kristen E. Nailor、Jeffrey N. Johnston
DOI:10.1021/ol027064u
日期:2002.11.1
The first examples of free radical-mediated vinyl amination are described by nonconventional vinyl radical addition to azomethine nitrogen. This new vinyl amination protocol is mild and provides convenient synthetic access to nonstabilized N,N-dialkyl enamines and tandem bond-forming processes.