Abstract
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).
Original language | English (US) |
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Pages (from-to) | 11197-11204 |
Number of pages | 8 |
Journal | Journal of the American Chemical Society |
Volume | 137 |
Issue number | 34 |
DOIs | |
State | Published - Sep 2 2015 |
ASJC Scopus subject areas
- Catalysis
- Chemistry(all)
- Biochemistry
- Colloid and Surface Chemistry