Photochemical transformations of some neoclerodane and labdane diterpene ketones

European Journal of Organic Chemistry

Volumn , Issue 9, 1999, Pages 2011-2015

  Fontana, Gianfranco ^a   Savona, Giuseppe ^a   Vivona, Nicolò ^a   Rodríguez, Benjamín ^b  

^a UNIVERSITY OF PALERMO   (Italy)

^b CSIC   (Spain)

Author keywords

Fruticolide; Fruticolone; Hydroxy ketones; Lactones; Epoxy ketones; Diketones

Indexed keywords

CLERODANE DERIVATIVE; DITERPENE; KETONE DERIVATIVE;

ARTICLE; CHEMICAL REACTION; DRUG ISOLATION; DRUG TRANSFORMATION; EXTRACTION; IRRADIATION; PHOTOCHEMISTRY; PHOTOLYSIS; REACTION ANALYSIS; STRUCTURE ANALYSIS;

EID: 0032856401     PISSN: 1434193X     EISSN: None     Source Type: Journal    
DOI: 10.1002/(sici)1099-0690(199909)1999:9<2011::aid-ejoc2011>3.0.co;2-%23     Document Type: Article

References (28)

1. Although the hydrocarbon skeleton of these diterpenes is biogenetically derived from an ent-labdane and hence they should be named ent-clerodanes, we prefer to use the term neoclerodane proposed by Rogers et al. for defining the absolute configuration (D. Rogers, G. G. Unal, D. J. Williams, S. V. Ley, G. A. Sim, B. S. Joshi, K. R. Ravindranath, J. Chem. Soc., Chem. Commun. 1979, 97-99) since this nomenclature is adopted in the majority of the articles published on this subject since 1979.
2. [2a] A. T. Merritt, S. V. Ley, Nat. Prod. Rep. 1992, 9, 243-287.
3. [2b] L. Rodríguez-Hahn, B. Esquivel, J. Cárdenas in: Progress in the Chemistry of Organic Natural Products (Eds.: W. Herz, G. W. Kirby, R. E. Moore, W. Steglich, Ch. Tamm), Springer-Verlag, Vienna, 1994, vol. 63, pp. 107-196.
4. [2c] F. Piozzi, B. Rodríguez, G. Savona, Heterocycles 1987, 25, 807-841.
5. [2d] F. Piozzi, Heterocycles 1994, 37, 603-626.
6. [3a] M. S. J. Simmonds, W. M. Blaney in: Advances in Labiate Science (Eds.: R. M. Harley, T. Reynolds) Royal Botanic Gardens, Kew, U.K., 1992, pp. 375-392.
7. [3b] M. S. J. Simmonds, W. M. Blaney, S. V. Ley, G. Savona, M. Bruno, B. Rodríguez, Phytochemistry 1989, 28, 1069-1071.
8. [3c] F. Ortego, B. Rodríguez, P. Castañera, J. Chem. Ecol. 1995, 21, 1375-1386.
9. [3d] R. D. Enriz, H. A. Baldoni, E. A. Jauregui, M. E. Sosa, C. E. Tonn, O. S. Giordano, J. Agric. Food Chem. 1994, 42, 2958-2963.
10. [4a] S. A. Kouzi, R. J. McMurtry, S. D. Nelson, Chem. Res. Toxicol. 1994, 7, 850-856.
11. [4b] M. Lekehal, D. Pessayre, J. M. Lereau, C. Moulis, I. Fourasté, D. Fau, Hepatology 1996, 24, 212-218.
12. [5a] M. C. de la Torre, B. Rodríguez, M. Bruno, C. Fazio, K. H. C. Baser, H. Duman, Phytochemistry 1997, 45, 1653-1662.
13. [5b] E. Mössner, M. C. de la Torre, B. Rodríguez, J. Nat. Prod. 1996, 59, 367-373.
14. [5c] G. Fontana, M. P. Paternostro, G. Savona, B. Rodríguez, M. C. de la Torre, J. Nat. Prod. 1998, 61, 1242-1247.
15. M. Bruno, R. Alcázar, M. C. de la Torre, F. Piozzi, B. Rodríguez, G. Savona, A. Perales, N. A. Arnold, Phytochemistry 1992, 31, 3531-3534.
16. [7a] G. Savona, S. Passannanti, M. P. Paternostro, F. Piozzi, J. R. Hanson, P. B. Hitchcock, M. Siverns, J. Chem. Soc., Perkin Trans. 1 1978, 356-359.
17. [7b] G. Savona, S. Passannanti, M. P. Paternostro, F. Piozzi, J. R. Hanson, M. Siverns, Phytochemistry 1978, 17, 320-322.
18. G. Savona, F. Piozzi, B. Rodríguez, Heterocycles 1978, 9, 257-261.
19. M. C. García-Alvarez, L. Pérez-Sirvent, B. Rodríguez, M. Bruno, G. Savona, An. Quím. 1981, 77, 316-319.
20. N. J. Turro, Modern Molecular Photochemistry, Benjamin, Cummings, Menlo Park, California, 1978.
21. [11a] E. L. Ghisalberti, P. R. Jefferies, M. A. Sefton, Tetrahedron 1978, 34, 3337-3340.
22. [11b] S. Stiver, P. Yates, Can. J. Chem. 1988, 66, 214-226, and references cited therein.
23. In compound 7, irradiation at δ = 4.54 (16β-H) under NOE conditions caused enhancements in the 7α-H (δ = 2.85, 3%) and 15-H (δ = 6.43, 1%) protons, but this result does not provide any reliable information about the stereochemistry at C-16. However, a structure with the opposite configuration at the C-13 and C-16 carbon atoms is not possible, because of the presence in 7 of an additional five-membered carbocycle comprising the C-8, C-9, C-11, C-12, and C-13 carbon atoms (see a molecular model of 7).
24. [13a] G. Büchi, I. M. Goldman, J. Am. Chem. Soc. 1957, 79, 4741-4748.
25. [13b] C. H. Heathcock, R. M. Badger, J. Chem. Soc., Chem. Commun. 1968, 1510-1511.
26. [14a] H. Wehrli, C. Lehmann, K. Schaffner, O. Jeger, Helv. Chim. Acta 1964, 47, 1336-1340.
27. [14b] H. Wehrli, C. Lehmann, P. Keller, J. J. Bonet, K. Schaffner, O. Jeger, Helv. Chim. Acta 1966, 49, 2218-2256.
28. [14c] H. Wehrli, C. Lehmann, T. Iizuka, K. Schaffner, O. Jeger, Helv. Chim. Acta 1967, 50, 2403-2420.