959922-63-5Relevant articles and documents
The synthesis of azadirachtin: A potent insect antifeedant
Ley, Steven V.,Abad-Somovilla, Antonio,Anderson, James C.,Ayats, Carles,Baenteli, Rolf,Beckmann, Edith,Boyer, Alistair,Brasca, Maria G.,Brice, Abigail,Broughton, Howard B.,Burke, Brenda J.,Cleator, Ed,Craig, Donald,Denholm, Alastair A.,Denton, Ross M.,Durand-Reville, Thomas,Gobbi, Luca B.,Goebel, Michael,Gray, Brian Lawrence,Grossmann, Robert B.,Gutteridge, Claire E.,Hahn, Norbert,Harding, Sarah L.,Jennens, David C.,Jennens, Lynn,Lovell, Peter J.,Lovell, Helen J.,De La Puente, Mary L.,Kolb, Hartmuth C.,Koot, Win-Jan,Maslen, Sarah L.,McCusker, Catherine F.,Mattes, Amos,Pape, Andrew R.,Pinto, Andrea,Santafianos, Dinos,Scott, James S.,Smith, Stephen C.,Somers, Andrew Q.,Spilling, Christopher D.,Stelzer, Frank,Toogood, Peter L.,Turner, Richard M.,Veitch, Gemma E.,Wood, Anthony,Zumbrunn, Cornelia
experimental part, p. 10683 - 10704 (2009/12/31)
We describe in full the first synthesis of the potent insect antifeedant azadirachtin through a highly convergent approach. An O-alkylation reaction is used to unite decalin ketone and propargylic mesylate fragments, after which a Claisen rearrangement constructs the central C8-C14 bond in a stereoselective fashion. The allene which results from this sequence then enables a second critical carboncarbon bond forming event whereby the [3.2.1] bicyclic system, present in the natural product, is generated via a 5-exo-radical cyclisation process. Finally, using knowledge gained through our early studies into the reactivity of the natural product, a series of carefully designed steps completes the synthesis of this challenging molecule.
