6879-73-8Relevant articles and documents
Total Synthesis of the Galbulimima Alkaloids Himandravine and GB17 Using Biomimetic Diels-Alder Reactions of Double Diene Precursors
Larson, Reed T.,Pemberton, Ryan P.,Franke, Jenna M.,Tantillo, Dean J.,Thomson, Regan J.
, p. 11197 - 11204 (2015)
The enantioselective total syntheses of himandravine and GB17 were completed through a common biomimetic strategy involving Diels-Alder reactions of unusual double diene containing linear precursors. The double diene precursors, containing or lacking a C12 substituent as required to produce GB17 or himandravine, respectively, were found to undergo Diels-Alder reactions to afford mixtures of regioisomeric cycloadducts that map onto the alternative carbocyclic frameworks of both himandravine and GB17. Computational investigations revealed that these Diels-Alder reactions proceed via transition state structures of similar energy that have a high degree of bispericyclic character and that the low levels of regioselectivity observed in the reactions are a consequence of competing orbital interaction and distortion energies. The combined experimental and computational results provide valuable insights into the biosynthesis of the Galbulimima alkaloids. (Chemical Equation Presented).
Biomimetic approach to Galbulimina type I alkaloids
Tchabanenko, Kirill,Chesworth, Richard,Parker, Jeremy S.,Anand, Neel K.,Russell, Andrew T.,Adlington, Robert M.,Baldwin, Jack E.
, p. 11649 - 11656 (2007/10/03)
On treatment with trifluoroacetic acid the tetraene precursor 23 underwent Boc deprotection, condensation and an iminium ion accelerated intramolecular Diels-Alder cycloaddition resulting in an iminium species 12, which was further converted into himbacin
