Crystal structures of three bicyclic carbohydrate derivatives
- The title compounds, [(1R,3R,4R,5R,6S)-4,5-bis(acetyloxy)-7-oxo-2-oxabicyclo-
[4.2.0]octan-3-yl]methyl acetate, C14H18O8, (I), [(1S,4R,5S,6R)-5-acetyloxy-7-
hydroxyimino-2-oxobicyclo[4.2.0]octan-4-yl acetate, C11H15NO6, (II), and
[(3aR,5R,6R,7R,7aS)-6,7-bis(acetyloxy)-2-oxooctahydropyrano[3,2-b]pyrrol-5-
yl]methyl acetate, C14H19NO8, (III), are stable bicyclic carbohydrate derivatives.
They can easily be synthesized in a few steps from commercially available
glycals. As a result of the ring strain from the four-membered rings in (I) and
(II), the conformations of the carbohydrates deviate strongly from the ideal
chair form. Compound (II) occurs in the boat form. In the five-membered
lactam (III), on the other hand, the carbohydrate adopts an almost ideal chair
conformation. As a result of the distortion of the sugar rings, the configurations
of the three bicyclic carbohydrate derivatives could not be determined from
their NMR coupling constants. From our three crystal structure determinations,
we were able to establishThe title compounds, [(1R,3R,4R,5R,6S)-4,5-bis(acetyloxy)-7-oxo-2-oxabicyclo-
[4.2.0]octan-3-yl]methyl acetate, C14H18O8, (I), [(1S,4R,5S,6R)-5-acetyloxy-7-
hydroxyimino-2-oxobicyclo[4.2.0]octan-4-yl acetate, C11H15NO6, (II), and
[(3aR,5R,6R,7R,7aS)-6,7-bis(acetyloxy)-2-oxooctahydropyrano[3,2-b]pyrrol-5-
yl]methyl acetate, C14H19NO8, (III), are stable bicyclic carbohydrate derivatives.
They can easily be synthesized in a few steps from commercially available
glycals. As a result of the ring strain from the four-membered rings in (I) and
(II), the conformations of the carbohydrates deviate strongly from the ideal
chair form. Compound (II) occurs in the boat form. In the five-membered
lactam (III), on the other hand, the carbohydrate adopts an almost ideal chair
conformation. As a result of the distortion of the sugar rings, the configurations
of the three bicyclic carbohydrate derivatives could not be determined from
their NMR coupling constants. From our three crystal structure determinations,
we were able to establish for the first time the absolute configurations of all new
stereocenters of the carbohydrate rings.…
Verfasserangaben: | Uwe SchildeORCiDGND, Alexandra Kelling, Sumaira Umbreen, Torsten LinkerORCiDGND |
---|---|
DOI: | https://doi.org/10.1107/S2056989016018727 |
ISSN: | 2056-9890 |
Titel des übergeordneten Werks (Englisch): | Acta crystallographica Section E ; Crystallographic communications |
Verlag: | IUCR |
Verlagsort: | Chester |
Publikationstyp: | Wissenschaftlicher Artikel |
Sprache: | Englisch |
Datum der Erstveröffentlichung: | 29.11.2016 |
Erscheinungsjahr: | 2016 |
Veröffentlichende Institution: | Universität Potsdam |
Datum der Freischaltung: | 16.12.2016 |
Freies Schlagwort / Tag: | carbohydrate derivatives; configuration; conformation; crystal structure |
Band: | 72 |
Ausgabe: | 12 |
Erste Seite: | 1839 |
Letzte Seite: | 1844 |
Fördernde Institution: | Universität Potsdam, Publikationsfonds |
Fördernummer: | PA 2016_43 |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Peer Review: | Referiert |
Fördermittelquelle: | Publikationsfonds der Universität Potsdam |
Publikationsweg: | Open Access |
Lizenz (Deutsch): | ![]() |
Externe Anmerkung: | Zweitveröffentlichung in der Schriftenreihe Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe ; 296 |