Simple enantioselective total synthesis of glabrescol, a chiral C2-symmetric pentacyclic oxasqualenoid [17]

Journal of the American Chemical Society

Volumn 122, Issue 38, 2000, Pages 9328-9329

  Xiong, Zhaoming ^a   Corey, E J ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

GLABRESCOL; SQUALENE DERIVATIVE; UNCLASSIFIED DRUG;

CHIRALITY; DRUG STRUCTURE; DRUG SYNTHESIS; ENANTIOMER; LETTER; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0034721450     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja0024901     Document Type: Letter

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12. 3N in THF, at -45 °C for 45 min) and in situ displacement of mesylate by addition of 5 equiv of LiBr, and reaction at 0 °C for 1 h. (b) See also: Huang, A. X.; Xiong, Z.; Corey, E. J. J. Am. Chem. Soc. 1999, 121, 9999.
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19. 2O); 6, 0.15 (1:1 hex-EtOAc); 8, 0.24 (10:1 EtOAc-EtOH); 9, 0.26 (1:2 hex-EtOAc); 10, 0.19 (1:2 hex-EtOAc); 3, 0.37 (1:2 hex-EtOAc).
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21. 2.
22. Kindly provided by Dr. Helen Jacobs, University of the West Indies.
23. Personal communication to E.J.C. from Dr. Helen Jacobs, May 3, 2000. We are indebted to Dr. Jacobs for this information and for her generous assistance in this research.
24. 3).
25. 3 substituents at C(2) and C(5) of the two equivalent A rings and also the two equivalent B rings, as required by that structure.