Theopalauamide, a Bicyclic Glycopeptide from Filamentous Bacterial Symbionts of the Lithistid Sponge Theonella swinhoei from Palau and Mozambique

Journal of Organic Chemistry

Volumn 63, Issue 4, 1998, Pages 1254-1258

  Schmidt, Eric W ^a   Bewley, Carole A ^a   Faulkner, D John ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001475887     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo9718455     Document Type: Article

References (13)

1. (a) Bewley, C. A.; Faulkner, D. J. Angew. Chem., Int. Edit. Engl. Submitted,
2. (b) Faulkner, D. J. Nat. Prod. Rep. 1997, 14, 259-302 and previous reports in this series.
3. Bewley, C. A.; Holland, N. D.; Faulkner, D. J. Experientia 1996, 52, 716-722.
4. The name isotheopalauamide is used because compound 2 is a stable conformational isomer of theopalauamide (1) with different physical and spectral properties. There does not appear to be a special prefix to describe this situation.
5. Bewley, C. A.; Faulkner, D. J. J. Org. Chem. 1994, 59, 4849-4852.
6. We eventually found that isomerization occurred during removal of the solvent after HPLC separation and that isomerization could be suppressed by addition of ammonia to neutralize the TFA.
7. Stothers, J. B. Carbon-13 NMR Spectroscopy; Academic Press: New York, 1972; p 461.
8. Matsunaga, S.; Fusetani, N.; Hashimoto, K.; Walchli, M. J. Am. Chem. Soc. 1989, 111, 2582-2588.
9. 7 reported that hydrogenation of theonellamide F followed by hydrolysis of the peptide and 2,4-DNP derivatization gave a 5:1 mixture of epimers, of which the major isomer was identical to lactone 4. When we hydrogenated theonellamide F and performed the standard hydrolysis and derivatization for GC-MS analysis, we found that the retention time of the minor peak resulting from the AHMP residue was approximately the same as that of the major peak produced by hydrogenation, hydrolysis, and derivatization of isotheopalauamide (2).
10. Morita, H.; Kayashita, T.; Takeya, K.; Itokawa, H.; Shiro, M. tetrahedron 1997, 53, 1607-1616.
11. A search of the marine natural product literature failed to Provide other examples of the isolation of stable conformers of cyclic Peptides.
12. For general experimental procedures, see: Schmidt, E. W.; Harper, M. K.; Faulkner, D. J. J. Nat. Prod. 1997, 60, 779-782.
13. Kho, E.; Imagawa, D. K.; Rohmer, M.; Kashman, Y.; Djerassi, C. J. Org. Chem. 1981, 46, 1836-1839.