Syntheses and stereochemical revision of pseudopterosin G - J aglycon and helioporin E

Organic Letters

Volumn 2, Issue 15, 2000, Pages 2389-2392

  Lazerwith, Scott E ^a   Johnson, Ted W ^a   Corey, E J ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BROMOBENZOIC ACID DERIVATIVE; DITERPENE; GLYCOSIDE; HELIOPORIN E; NONSTEROID ANTIINFLAMMATORY AGENT; POLYCYCLIC HYDROCARBON; PSEUDOPTEROSINS;

ARTICLE; CHEMISTRY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; STEREOISOMERISM; SYNTHESIS; X RAY CRYSTALLOGRAPHY;

ANTI-INFLAMMATORY AGENTS, NON-STEROIDAL; BROMOBENZOATES; CRYSTALLOGRAPHY, X-RAY; DITERPENES; GLYCOSIDES; MAGNETIC RESONANCE SPECTROSCOPY; POLYCYCLIC COMPOUNDS; STEREOISOMERISM;

EID: 0034720927     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol006192k     Document Type: Article

References (31)

1. Corey, E. J.; Lazerwith, S. E. J. Am. Chem. Soc. 1998, 120, 12777.
2. For other synthetic routes to the pseudopterosin family, see: (a) Broka, C. A.; Chan, S.; Peterson, B. J. Org. Chem. 1988, 53, 1584.
3. (b) Corey, E. J.; Carpino, P. J. Am. Chem. Soc. 1989, 111, 5472.
4. (c) Corey, E. J.; Carpino, P. Tetrahedron Lett. 1990, 31, 3857.
5. (d) McCombie, S. W.; Cox, B.; Lin, S.-I.; Ganguly, A. K.; McPhail, A. T. Tetrahedron Lett. 1991, 32, 2083.
6. (e) McCombie, S. W.; Ortiz, C.; Cox, B.; Ganguly, A. K. Synlett 1993, 541.
7. (f) Buszek, K. R. Tetrahedron Lett. 1995, 36, 9125.
8. (g) Buszek, K. R.; Bixby, D. L. Tetrahedron Lett. 1995, 36, 9129.
9. (h) Gill, S.; Kocienski, P.; Kohler, A.; Pontiroli, A.; Qun, L. J. Chem. Soc., Chem. Commun. 1996, 1743.
10. (i) Majdalani, A.; Schmalz, H.-G. Tetrahedron Lett. 1997, 38, 4545.
11. (j) Majdalani, A.; Schmalz, H.-G. Synlett 1997, 1303.
12. (k) Kato, N.; Zhang, C.-S.; Matsui, T.; Iwabachi, H.; Mori, A.; Ballio, A.; Sassa, T. J. Chem. Soc., Perkin Trans. 1 1998, 2475.
13. In these cases, the peak shapes are similar broad doublets with couplings of approximately 9 Hz.
14. 3 arises from the deprotection of 6 (see ref 1).
15. 15 arises via the deprotection of 7 (sed Schemes 2 and 3 below).
16. Rousis, V.; Wu, Z.; Fenical, W.; Strobel, S. A.; Van Duyne, G. D.; Clardy, J. J. Org. Chem. 1990, 55, 4916.
17. Pseudopterosins G - J were originally assigned to be C(7) diastereomers of pseudopterosins A - F by NOE experiments. See ref 6.
18. For isolation and original structural determinanon of the helioporins, see; Tanaka, J.-i.; Ogawa, N.; Liang, J.; Higa, T.; Gravalos, D. G. Tetrahedron 1993, 49, 811.
19. For structural revision of helioporin C and D, see: (a) Geller, T.; Schmalz, H.-G.; Bats, J. W. Tetrahedron Lett. 1998, 39, 1537.
20. (b) Hörstermann, D.; Schmalz, H.-G.; Kociok-Köhn, G. Tetrahedron 1999, 55, 6905.
21. Shimshock, S. J.; Waltermire, R. E.; DeShong, P. J. Am. Chem. Soc. 1991, 113, 8791.
22. A natural sample of pseudopterosin I was generously donated by Professor William Fenical. It was converted into its methylated aglycon by (1) treatment with methyl iodide and potassium carbonate in hot acetone to afford a mixture of methylated products (arising from acetyl migration in the sugar portion of the molecule) and (2) deglycosylation with HCl (aq) in methanol. See ref 6.
23. 3).
24. Professor Fenical and co-workers independently discovered indirect evidence for this stereochemical reassignment, but lacked experimental proof (personal communication).
25. Stereochemical assignments for pseudopterosins G - J were made by NOE. See ref 6.
26. Clark, J. H.; Holland, H. L.; Miller, J. M. Tetrahedron Lett. 1976, 38, 3361.
27. 1H NMR spectrum of helioporin E (16).
28. A similar reassignment was hypothesized by Schmalz and co-workers. See ref 8b.
29. 2, followed by preparative TLC purification. Recrystallization from methol afforded X-ray quality crystals, mp 140-144 °C.
30. Detailed X-ray crystallographic data are available from the Cambridge Crystallographic Data Center, 12 Union Road, Cambridge CB2 1EZ, U.K.
31. Rodríguez, A. D.; Ramírez, C.; Rodríguez, I. I.; González, E. Org. Lett. 1999, 1, 527.