Total synthesis and assignment of stereochemistry of raocyclamide cyclopeptides from cyanobacterium Oscillatoria raoi

Tetrahedron Letters

Volumn 39, Issue 20, 1998, Pages 3251-3254

  Freeman, David J ^a   Pattenden, Gerald ^a  

^a UNIVERSITY OF NOTTINGHAM   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

CYCLOPEPTIDE; RAOCYCLAMIDE; UNCLASSIFIED DRUG;

AMINO ACID ANALYSIS; ARTICLE; CYANOBACTERIUM; DRUG ISOLATION; HIGH PERFORMANCE LIQUID CHROMATOGRAPHY; PROTEIN FOLDING; STEREOCHEMISTRY; STRUCTURE ACTIVITY RELATION; SYNTHESIS;

EID: 0032516335     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(98)00404-3     Document Type: Article

References (18)

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10. 3. Boden, C. D. J.; Pattenden, G. Tetrahedron Lett. 1995, 36, 6153-6156; Boden, C. D. J.; Pattenden, G. Tetrahedron Lett. 1994, 35, 8271-8274; Wipf, P. Chem. Rev. 1995, 95, 2115-2134.
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12. 5. Meyers, A.I.; Tavares, F.X. J. Org. Chem. 1996, 61, 8207-8215; this oxazole was reported as an oil with an [α]D -29 whereas in our hands it was a white crystalline solid with an [α]D -50.
13. 6. Satisfactory spectroscopic and mass spectrometry data were obtained for all new compounds.
14. 7. The ethyl ester corresponding to 9 has been prepared by an alternative route. See: Hamada, H.; Shibata, M.; Sugiura, T.; Kato, S.; Shioiri, T. J. Org. Chem. 1987, 52, 1252-1255.
15. 8. (a) Burgess, E.M.; Penton, Jr., H.R.; Taylor, E.A. J. Org. Chem. 1973, 38, 26-31.
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17. 3), 7.21 (5H, m, Ph), 7.78 (1H, s, SCH), 7.83 (1H, d, J 7.2, NHCO), 7.84 (1H, d, J 8.0, NHCO), 8.18 (1H, s, OCH), 8.32 (2H, m, 2 x NHCO).
18. 3) 11.9 (q), 15.7 (q), 20.2 (q), 24.2 (q), 37.7 (t), 42.3 (d), 44.8 (d), 48.0 (d), 55.6 (d), 67.6 (d), 69.9 (d), 124.6 (d), 125.9 (d), 127.6 (d), 129.5 (d), 134.9 (s), 135.6 (s), 141.0 (d), 147.8 (s), 159.3 (s), 159.5 (s), 164.1 (s), 167.0 (s), 169.5 (s), 170.1 (s).