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| Titel: |
Synthesis and Structural Analysis of Higher Analogs of Sucrose |
| Auteur: |
Jarosz, Slawomir Mach, Mateusz Frelek, Jadwiga |
| Verschenen in: |
Journal of carbohydrate chemistry |
| Paginering: | Jaargang 19 (2000) nr. 6 pagina's 693-715 |
| Jaar: |
2000 |
| Inhoud: |
Three sucrose monoalcohols with free hydroxyl groups at C-1', C-6, and C-6' (1, 4, and 6) were prepared selectively and in good yield from 2,3,3',4,4'-penta-O-benzylsucrose. These compounds were oxidized to aldehydes and reacted with stabilized ylide, Ph3P=CHCO2Me to afford appropriate α,β-unsaturated esters 10, 11, and 12. Each olefin was cis-hydroxylated with OsO4/NMO to stereoisomeric diols 13/14, 15/16, and 17/18, configurations of which were assigned by chemical correlation and CD evaluation. Stereoselectivity of the osmylation reaction was surprisingly low (ca 3:2), especially as compared to a similar process performed on simple derivatives of 6,7-unsaturated methyl glycosides for which the ratio of isomeric diols was assigned as 10:1. The osmylation of 11 (derivative homologated by a C2-unit at the glucose part) did not obey Kishi's rule. Horner-Emmons reaction of sucrose aldehyde 7 with a sugar-derived phosphonate 22 afforded α,β-unsaturated derivative 24, homologated by a C7-unit at the glucose end. |
| Uitgever: |
Taylor & Francis |
| Bronbestand: |
Elektronische Wetenschappelijke Tijdschriften |
Details van artikel 8 van 9 gevonden artikelen
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