Unexpected Dramatic Substituent Effect for Tuning the Selectivity in the Double Ring-Closing Metathesis Reaction of N-Containing Tetraenes. An Efficient Synthesis of Bicyclic Izidine Alkaloid Skeletons
作者:Shengming Ma、Bukuo Ni
DOI:10.1021/ol0172673
日期:2002.2.1
[reaction: see text] A doublering-closingmetathesisreaction for the efficientconstruction of the fused bicyclic izidine alkaloidskeleton was developed. In this reaction, high selectivity was realized by tuning of electronic and steric effects of substituents in the N-containing tetraenes. It was observed that the reactivity of electron-rich carbon-carbon double bonds is higher than that of electron-deficient
Synthetic Transformations of Sulfur-Substituted 4-Quinolizidinones
作者:Shang-Shing P. Chou、Chao-Hsiang Kao
DOI:10.1002/jccs.201300250
日期:2013.7.26
Sulfur‐substituted 4‐quinolizidinones, previously prepared by aza‐Diels‐Alderreactions and ring‐closing metathesis, are now subjected to further synthetic transformations. Formal synthesis of cermizine C and 5‐epi‐cermizine C, and some other useful reactions have been achieved.