Brønsted acid-promoted glycosylations of disaccharide glycal substructures of the saccharomicins

Organic Letters

Volumn 11, Issue 21, 2009, Pages 4850-4853

  Balthaser, Bradley R ^a   McDonald, Frank E ^a  

^a EMORY UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ANTIINFECTIVE AGENT; DISACCHARIDE; FUCOSE; OLIGOSACCHARIDE; SACCHAROMICIN A;

ACTINOBACTERIA; ARTICLE; CATALYSIS; CHEMICAL STRUCTURE; CHEMISTRY; GLYCOSYLATION; STEREOISOMERISM; SYNTHESIS;

ACTINOBACTERIA; ANTI-BACTERIAL AGENTS; CATALYSIS; DISACCHARIDES; FUCOSE; GLYCOSYLATION; MOLECULAR STRUCTURE; OLIGOSACCHARIDES; STEREOISOMERISM;

EID: 70350630571     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol901923x     Document Type: Article

References (25)

1. (a) Kong, F.; Zhao, N.; Siegel, M. M.; Janota, K.; Ashcroft, J. S.; Koehn, F. E.; Borders, D. B.; Carter, G. T. J. Am. Chem. Soc. 1998, 120, 13301.
2. (b) Singh, M. P.; Petersen, P. J.; Weiss, W. J.; Kong, F.; Greenstein, M. Antimicrob. Agents Chemother. 2000, 44, 2154.
3. Pletcher, J. M.; McDonald, F. E. Org. Lett. 2005, 7, 4749.
4. Cutchins, W. W.; McDonald, F. E. Org. Lett. 2002, 4, 749.
5. (a) Schmidt, R. R.; Wegmann, B.; Jung, K.-H. Liebigs Ann. Chem. 1991, 121.
6. (b) Schmidt, R. R.; Kinzy, W. Adv. Carbohydr. Chem. Biochem. 1994, 50, 21.
7. The identity of glycosides 6 and 7 was confirmed by X-ray crystallography (Supporting Information).
8. (a) Corey, E. J.; Bakshi, R. K. Tetrahedron Lett. 1990, 31, 611.
9. (b) Corey, E. J.; Helal, C. J. Angew. Chem., Int. Ed. 1998, 37, 1986.
10. A variety of substrate-controlled reduction methods gave poor stereoselectivity; see Supporting Information for a summary of these results. The (R)-diastereomer was produced in approximately 5% yield in the oxazaborolidine reduction and was recycled by IBX oxidation to the methyl ketone.
11. (a) Evans, C. M.; Kirby, A. J. J. Chem. Soc., Perkin Trans. II 1984, 1269.
12. (b) Hecker, S. J.; Heathcock, C. H. J. Am. Chem. Soc. 1986, 108, 4586.
13. Desilylation with tetrabutylammonium fluoride in the presence of acetic acid gave byproducts consistent with hydration of the alkyne, possibly from 5-exo-cyclization of the alkynyl alcohol and hydrolysis of the exocyclic enol ether, whereas the desilylation with tetrabutylammonium difluorotriphenylsilane afforded good yields of alkynyl alcohol 10.
14. (a) Barluenga, J.; Diéguez, A.; Rodríguez, F.; Fananás, F. J.; Sordo, T.; Campomanes, P. Chem.-Eur. J. 2005, 11, 5735.
15. (b) Katz, T. J. Angew. Chem., Int. Ed. 2005, 44, 3010.
16. Fuchibe, K.; Iwasawa, N. Chem.-Eur. J. 2003, 9, 905.
17. Davidson, M. H.; McDonald, F. E. Org. Lett. 2004, 6, 1601.
18. We thank Drs. Fangming Kong and Guy T. Carter (Wyeth Research) for providing 1H and 13C NMR spectra of compound 3 (Supporting Information).
19. We thank Drs. Rui Cao and Kenneth I. Hardcastle (Emory University) for solving the crystal structure of compound 16 (Supporting Information).
20. The L-fucosyl-D-saccharosamine diastereomer of 16 has also been prepared by a similar protocol beginning with compound 7 (Supporting Information).
21. McDonald, F. E.; Reddy, K. S. Angew. Chem., Int. Ed. 2001, 40, 3653.
22. These results are consistent with anchimeric assistance from the N-carbonyl substituent at C3. For examples of glycosylations trans- to C3-ester substituents, see: (a) Tsai, T. Y. R.; Jin, H.; Wiesner, K. Can. J. Chem. 1984, 62, 1403.
23. (b) Komarova, B. S.; Tsvetkov, Y. E.; Knivel, Y. A.; Zähringer, U.; Pier, G. B.; Nifantiev, N. E. Tetrahedron Lett. 2006, 47, 3583.
24. Chiba, S.; Kitamura, M.; Narasaka, K. J. Am. Chem. Soc. 2006, 128, 6931.
25. McDonald, F. E.; Wu, M. Org. Lett. 2002, 4, 3979.