A relay route for the synthesis of azadirachtin

Angewandte Chemie - International Edition

Volumn 46, Issue 40, 2007, Pages 7633-7635

  Veitch, Gemma E ^a   Beckmann, Edith ^a   Burke, Brenda J ^a   Boyer, Alistair ^a   Ayats, Carles ^a   Ley, Steven V ^a  

^a UNIVERSITY OF CAMBRIDGE   (United Kingdom)

Author keywords

Azadirachtin; Degradation; Natural products; Total synthesis

Indexed keywords

CYCLIZATION; DEGRADATION; GAME THEORY; SYNTHESIS (CHEMICAL);

AZADIRACHTIN; CLAISEN REARRANGEMENT; NATURAL PRODUCTS; RADICAL CYCLIZATION;

INSECTICIDES;

AZADIRACHTIN; LIMONOID;

ARTICLE; CHEMICAL STRUCTURE; CHEMISTRY; CONFORMATION; OXIDATION REDUCTION REACTION; SYNTHESIS;

LIMONINS; MODELS, MOLECULAR; MOLECULAR CONFORMATION; OXIDATION-REDUCTION;

EID: 35048900932     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200703028     Document Type: Article

References (31)

1. J. H. Butterworth, E. D. Morgan, Chem. Commun. 1968, 23-24.
2. H. Schmutterer, The Neem Tree, VCH, Weinheim, 1995.
3. P. R. Zanno, I. Miura, K. Nakanishi, D. L. Elder, J. Am. Chem. Soc. 1975, 97, 1975-1977.
4. J. N. Bilton, H. B. Broughton, S. V. Ley, Z. Lidert, E. D. Morgan, H. S. Rzepa, R. N. Sheppard, J. Chem. Soc. Chem. Commun. 1985, 968-971.
5. W. Kraus, M. Bokel, A. Klenk, H. Poehnl, Tetrahedron Lett. 1985, 26, 6435-6438.
6. H. B. Broughton, S. V. Ley, A. M. Z. Slawin, D. J. Williams, J. Chem. Soc. Chem. Commun. 1986, 46-47.
7. C. J. Turner, M. S. Tempesta, R. B. Taylor, M. G. Zagorski, J. S. Termini, D. R. Schroeder, K. Nakanishi, Tetrahedron 1987, 43, 2789-2803.
8. J. N. Bilton, H. B. Broughton, P. S. Jones, S. V. Ley, Z. Lidert, E. D. Morgan, H. S. Rzepa, R. N. Sheppard, A. M. Z. Slawin, D. J. Williams, Tetrahedron 1987, 43, 2805-2815.
9. W. Kraus, M. Bokel, A. Bruhn, R. Cramer, I. Klaiber, A. Klenk, G. Nagl, H. Poehnl, H. Sadlo, B. Volger, Tetrahedron 1987, 43, 2817-2830.
10. S. V. Ley, H. Lovell, D. J. Williams, J. Chem. Soc. Chem. Commun. 1992, 1304-1306.
11. S. V. Ley, K. Doherty, G. Massiot, J.-M. Nuzillard, Tetrahedron 1994, 50, 12267-12280.
12. For a review see A. J. Mordue, A. Blackwell, J. Insect Physiol. 1993, 39, 903-924.
13. S. V. Ley, J. C. Anderson, W. M. Blaney, E. D. Morgan, R. N. Sheppard, M. S. J. Simmonds, A. M. Z. Slawin, S. C. Smith, D. J. Williams, A. Wood, Tetrahedron 1991, 47, 9231-9246.
14. S. V. Ley, J. C. Anderson, W. M. Blaney, P. S. Jones, Z. Lidert, E. D. Morgan, N. G. Robinson, D. Santafianos, M. S. J. Simmonds, P. L. Toogood, Tetrahedron 1989, 45, 5175-5192.
15. M. S. J. Simmonds, W. M. Blaney, S. V. Ley, J. C. Anderson, P. L. Toogood, Entomol. Exp. Appl. 1990, 55, 169-181.
16. W. M. Blaney, M. S. J. Simmonds, S. V. Ley, J. C. Anderson, P. L. Toogood, Entomol. Exp. Appl. 1990, 55, 149-160.
17. S. V. Ley, J. C. Anderson, W. M. Blaney, P. S. Jones, L. Z. , E. D. Morgan, N. G. Robinson, D. Santafianos, M. S. J. Simmonds, P. L. Toogood, Tetrahedron 1989, 45, 5175-5192.
18. S. V. Ley, A. A. Denholm, A. Wood, Nat. Prod. Rep. 1993, 10, 109-157.
19. J. N. Bilton, P. S. Jones, S. V. Ley, N. G. Robinson, R. N. Sheppard, Tetrahedron Lett. 1988, 29, 1849-1852.
20. S. Johnson, E. D. Morgan, I. D. Wilson, M. Spraul, M. Hofmann, J. Chem. Soc. Perkin Trans. 1 1994, 1499-1502.
21. A. A. Denholm, L. Jennens, S. V. Ley, A. Wood, Tetrahedron 1995, 51, 6591-6604.
22. S. V. Ley, J. C. Anderson, W. M. Blaney, Z. Lidert, E. D. Morgan, N. G. Robinson, M. S. J. Simmonds, Tetrahedron Lett. 1988, 29, 5433-5436.
23. G. E. Veitch, E. Beckmann, B. J. Burke, A. Boyer, S. L. Maslen, S. V. Ley, Angew. Chem. 2007, 10.1002/ange.200703027;
24. Angew. Chem. Int. Ed. 2007, 10.1002/anie.200703027.
25. The availabilty of azadirachtin has permitted its use in this relay approach, however, it can only be obtained commercially as crude neem extract (30% azadirachtin), which requires extensive purification prior to use.
26. V. Kabaleeswaran, S. S. Rajan, T. R. Govindachari, G. Gopalakrishnan, Curr. Sci. 1994, 66, 392-394.
27. The C11,C20 dibenzylated compound was the major product, but it was accompanied by small quantities of mixed-alkylation products, the ratios of which were dependent on the reaction conditions.
28. C1 reactivity during alkylation reactions was in all examples lower than at any other position, presumbaly owing to steric constraints imposed by the molecule's conformation.
29. Selectivity in the debenzylation was obtained by careful experimentation and solvent screening.
30. The tiglic acid/Yamaguchi mixed anhydride was purified prior to use, for details see M. Ball, S. P. Andrews, F. Wierschem, E. Cleator, M. Smith, S. V. Ley, Org. Lett. 2007, 9, 663-666.
31. J. L. Luche, J. Am. Chem. Soc. 1978, 100, 2226-2227.