Conformational equilibria in amino steroids derived from fusidic acid

Abstract

The conformation of ring A of the 3α-hydroxy-2β-piperidino steroid 9, derived from fusidic acid, has been investigated by ¹H NMR and is determined by the polarity of the medium: it is primarily in a twist-boat conformation in a non-polar solvent and a chair conformation in a polar solvent.

References

1. L. Fielding and G. H. Grant, J. Am. Chem. Soc., 1991, 113, 9785.
2. (a) L. Fielding, N. Hamilton, R. McGuire, M. Maidment and A. C. Campbell, Magn. Reson. Chem., 1996, 34, 59; (b) L. Fielding, N. Hamilton, R. McGuire, M. Maidment and A. C. Campbell, Bull. Magn. Reson., 1995, 17, 208; (c) L. Fielding, N. Hamilton and R. McGuire, Magn. Reson. Chem., 1997, 35, 184; L. Fielding, Magn. Reson. Chem., 1998, 36, 387.
3. A. W. Muir, J. Houston, K. L. Green, R. J. Marshall, W. C. Bowman and I. G. Marshall, Br. J. Anaesth., 1989, 63, 400.
4. W. C. Bowman, Trends Pharmacol. Sci., 1980, 1, 263.
5. (a) W. O. Godtfredsen, Fusidic Acid and Some Related Antibiotics, Aarhuus Stiftsbogtrykkerie, Copenhagen, 1967; (b) W. O. Godtfredsen, W. von Daehne, S. Vangedal, D. Arigoni, A. Marquet and A. Melera, Tetrahedron, 1965, 21, 3505; (c) A. Cooper and D. C. Hodgkin, Tetrahedron, 1968, 24, 909.
6. W. S. Murphy, B. Sarsam, G. Ferguson and J. F. Gallagher, J. Chem. Soc., Perkin Trans. 1, 1998, 4121.
7. P. A. Diassi, I. Basco, G. W. Krakower and H. A. Van Dine, Tetrahedron, 1966, 22, 3459.
8. J. L. Beton, T. G. Halsall, E. R. H. Jones and P. C. Phillips, J. Chem. Soc., 1957, 753.
9. M. Tanabe, D. M. Yasuda and R. H. Peters, Tetrahedron Lett., 1977, 1481.
10. W. von Daehne, W. O. Godfredsen and P. R. Rasmussen, Adv. Appl. Microbiol., 1979, 25, 95.
11. E. Batres, G. Monroy and H. J. Ringold, J. Org. Chem., 1961, 26, 878; A. C. Campbell, Eur. Pat., 1995, 656365.
12. W. R. Buckett, C. L. Hewett and D. S. Savage, J. Med. Chem., 1973, 16, 1116.
13. J. R. Hanson, P. B. Hitchcock, V. Thangavelu and C. Uyanik, J. Chem. Res., 1999, 256.
14. N. L. Allinger, J. Am. Chem. Soc., 1977, 99, 8127.
15. L. Fielding and G. H. Grant, J. Am. Chem. Soc., 1993, 115, 1902.
16. D. S. Savage, A. F. Cameron, G. Ferguson, C. Hannaway and I. R. Mackay, J. Chem. Soc. B., 1971, 410.
17. W. S. Murphy and D. Cocker, J. Chem. Soc., Perkin Trans. 1, 1977, 2565.
18. T. Riisom, H. J. Jakobsen, N. Rastrup-Anderson and H. Lorck, Tetrahedron Lett., 1974, 2247.