Authors: | Randolph, J. T.; Danishefsky, S. J. |
Article Title: | First synthesis of a digitalis saponin. Demonstration of the scope and limitations of a convergent scheme for branched oligosaccharide synthesis by the logic of glycal assembly |
Abstract: | The synthesis of complex glycosides, with branching at C2, is demonstrated. The key element involves the use of a 1, 2-oxirane donor. Upon glycosylation, a C2 hydroxyl is exposed to serve as the acceptor in the next glycosylation. Branching at C2 with a β-linked glycoside at C1 was not achievable with epoxy 23 donor, but was accomplished with fluoro donor 25, in turn derived from 23. (See 19 + 18 → 20; 20 + 25 → 26. Compound 26 was deprotected to complete the first total synthesis of a natural saponin, desgalactotigonin (3)). A limitation in stereospecifity in the use of donor 23 and monoprotected galactal acceptor 28 was also encountered. © 1995, American Chemical Society. All rights reserved. |
Keywords: | unclassified drug; methodology; drug synthesis; nuclear magnetic resonance; reaction analysis; stereochemistry; glycoside; saponin; article; degalactotigonin |
Journal Title: | Journal of the American Chemical Society |
Volume: | 117 |
Issue: | 21 |
ISSN: | 0002-7863 |
Publisher: | American Chemical Society |
Date Published: | 1995-05-31 |
Start Page: | 5693 |
End Page: | 5700 |
Language: | English |
DOI: | 10.1021/ja00126a010 |
PROVIDER: | scopus |
DOI/URL: | |
Notes: | Article -- Export Date: 28 August 2018 -- Source: Scopus |