Synfacts 2008(2): 0111-0111  
DOI: 10.1055/s-2007-992496
Synthesis of Natural Products and Potential Drugs
© Georg Thieme Verlag Stuttgart · New York

Relay Synthesis of Azadirachtin

Contributor(s):Philip Kocienski
G. E. Veitch, E. Beckmann, B. J. Burke, A. Boyer, S. L. Maslen, S. V. Ley*
University of Cambridge, UK
Synthesis of Azadirachtin: A Long but Successful Journey
Angew. Chem. Int. Ed.  2007,  46:  7629-7632  
Further Information

Publication History

Publication Date:
23 January 2008 (online)


Azadirachtin is an insect antifeedant. A major challenge in this 22-year odyssey was the construction of 16 contiguous stereogenic centers seven of which are quaternary. The excerpt depicted here focuses on the Claisen rearrangment used to construct the congested C8-C14 bond.


Compounds A and G were obtained by total synthesis and by degradation of azadirachtin. The degradation route enabled exploration of the difficult closing stages of the synthesis. Note the harsh conditions required to effect the difficult epoxidation FG.