Enantioselective synthesis of oasomycin A, part I: Synthesis of the C1-C12 and C13-C28 subunits

Angewandte Chemie - International Edition

Volumn 46, Issue 4, 2007, Pages 537-540

  Evans, David A ^a   Nagorny, Pavel ^a   McRae, Kenneth J ^a   Reynolds, Dominic J ^a   Sonntag, Louis Sebastian ^a   Vounatsos, Filisaty ^a   Xu, Risheng ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

Aldol reaction; Kocienski Julia olefination; Macrolactonization; Natural products; Total synthesis

Indexed keywords

ALDOL REACTION; KOCIENSKI JULIA OLEFINATION; MACROLACTONIZATION; NATURAL PRODUCTS; OASOMYCIN;

ACYLATION; ADDITION REACTIONS; METABOLITES; STEREOCHEMISTRY; SYNTHESIS (CHEMICAL); UNSATURATED COMPOUNDS;

KETONES;

ALDEHYDE; MACROLIDE; OASOMYCIN; UNCLASSIFIED DRUG;

ARTICLE; CHEMISTRY; HYDROGENATION; STEREOISOMERISM; SYNTHESIS;

ALDEHYDES; HYDROGENATION; MACROLIDES; STEREOISOMERISM;

EID: 33846495712     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200603653     Document Type: Article

References (34)

1. a) S. Grabley, G. Kretzschmar, M. Mayer, S. Philipps, R. Thiericke, J. Wink, A. Zeeck, Liebigs Ann. Chem. 1993, 5, 573-579;
2. b) M. Mayer, R. Thiericke, J. Chem. Soc. Ferkin Trans. 1 1993, 21, 2525-2531.
3. For the stereochemical assignment of oasomycin A, see: Y. Kobayashi, S.-H. Tan, Y. Kishi, J. Am. Chem. Soc. 2001, 123, 2076-2078, and references therein.
4. For the preparation of 1, see: a) D. A. Evans, M. D. Ennis, T. Le, N. Mandel, G. Mandel, J. Am. Chem. Soc. 1984, 106, 1154-1156;
5. b) D. A. Evans, J. R. Gage, Org. Synth. 1989, 68, 83-91.
6. T. Ishikawa, S. Ikeda, M. Ibe, S. Saito, Tetrahedron 1998, 54, 5869-5882.
7. A. M. P. Koskien, K. Karisalmi, Chem. Soc. Rev. 2005, 34, 677-690.
8. 13C NMR signals (δ = 97.9, 29.9, and 19.4 ppm) for the acetonide moiety confirmed that the aforementioned reduction proceeded to afford the syn diastereomer. a) S. D. Rychnovsky, D. J. Skalitzky, Tetrahedron Lett. 1990, 31, 945-948;
9. b) S. D. Rychnovsky, B. Rogers, G. Yang, J. Org. Chem. 1997, 62, 3511-3515;
10. c) D. A. Evans, D. L. Rieger, J. R. Gage, Tetrahedron Lett. 1990, 31, 7099-7100.
11. T. Oishi, T. Nakata, Acc. Chem. Res. 1984, 17, 338-344.
12. For the preparation of phosphonate 5, see: a) G. Pattenden, B. C. L. Weedon, J. Chem. Soc. C 1968, 1984-1997;
13. b) T. Kitara, A. Horiguchi, K. Mori, Tetrahedron 1988, 44, 4713-4720.
14. 4 olefin).
15. R. H. Crabtree, M. W. Davis, J. Org. Chem. 1986, 51, 2655-2661.
16. The mixture was separated by medium-pressure chromatography (MPLC).
17. 24] resulted in partial cleavage of the secondary TES group of 3 before the sulfoxide oxidation was complete (8-10%). The corresponding desilylated product could be recovered and reprotected (TESOTf, lutidine).
18. H. S. Schultz, H. B. Freyermuth, S. R. Buc, J. Org. Chem. 1963, 28, 1140-1142.
19. R. Baker, J. L. Castro, J. Chem. Soc. Perkin Trans. 1 1990, 47-65, and references therein.
20. For the synthesis of enantiomer 22, see: a) S. D. Rychnovsky, J. Org. Chem. 1989, 54, 4982-4984;
21. b) J. A. Christopher, P. J. Kocienski, A. Kuhl, R. Bell, Synlett 2000, 463-466;
22. c) M. J. Remuiñán, G. Pattenden, Tetrahedron Lett. 2000, 41, 7367-7371.
23. J. R. Parikh, W. von Doering, J. Am. Chem. Soc. 1967, 89, 5505-5507.
24. D. A. Evans, B. D. Allison, M. G. Yang, C. E. Masse, J. Am. Chem. Soc. 2001, 123, 10 840-10 852. The stereochemistry of the major allylation product was proven by comparing the spectroscopic characteristics of 22 to analogous compound 22 a, the stereochemistry of which was confirmed by X-ray crystallography. (Chemical Equation Presented)
25. B. S. Bal, W. E. Childers, H. W. Pinnick, Tetrahedron 1981, 37, 2091-2096.
26. J. M. Williams, R. B. Jobson, N. Yasuda, G. Marchesini, U-H. Dolling, E. J. Grabowski, Tetrahedron Lett. 1995, 36, 5461-5464.
27. For examples of acetoxysuccinic anhydride reactivity that illustrate the mentioned effect, see: D. J. Hart, T. K. Yang, J. Org. Chem. 1985, 50, 235-242;
28. S. Gogoi, N. P. Argade, Tetrahedron 2006, 62, 2999-3003, and references therein.
29. Both the presence of THF and transmetalation of 16b to 16c were essential for this reaction to run to completion. Thus, the acylations of 16b and 16c in the absence of THF proceeded in 45% and 66% yield respectively.
30. Y. Oikawa, T. Tanaka, K. Horita, T. Yoshioka, O. Yonemitsu, Tetrahedron Lett. 1984, 25, 5393-5396.
31. a) D. A. Evans, P. Nagorny, K. J. McRae, D. J. Reynolds, L.-S. Sonntag, F. Vounatsos, R. Xu, Angew. Chem. 2007, 119, 547-550;
32. Angew. Chem. Int. Ed. 2007, 46, 541-544;
33. b) D. A. Evans, P. Nagorny, K. J. McRae, L.-S. Sonntag, D. J. Reynolds, F. Vounatsos, Angew. Chem. 2007, 119, 551-554;
34. Angew. Chem. Int. Ed. 2007, 46, 545-548.