Kohlenhydrate mit 2,6‐Dioxabicyclo[3.3.0]octan‐Gerüst: Vergleichende Untersuchung von 3,6‐Anhydrohexofuranosederivaten mit D‐gluco‐, D‐manno‐, L‐ido‐ und L‐gulo‐Konfiguration

Köll, Peter; Komander, Herbert; Meyer, Bernd

doi:10.1002/jlac.198319830805

Cited by 19 publications

(1 citation statement)

References 47 publications

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“…However, during the purification by column chromatography, it was possible to separate the mixture into three fractions, including a fraction of pure α-6, which was used for the next step of the synthesis. The compound α-8 was identified by correlation 2D NMR experiments; the configuration was suggested based on NOE experiments and similarity with the known analogues [ 38 ]. Several 1 H NMR signals were overlapped, so we also recorded the NMR spectra in C 6 D 6 , in which the signals were more separated, and the NOE spectra were more reliable.…”

Section: Resultsmentioning

confidence: 99%

Selectivity of 1-O-Propargyl-d-Mannose Preparations

2022

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Thanks to their ability to bind to specific biological receptors, mannosylated structures are examined in biomedical applications. One of the most common ways of linking a functional moiety to a structure is to use an azide-alkyne click reaction. Therefore, it is necessary to prepare and isolate a propargylated mannose derivative of high purity to maintain its bioactivity. Three known preparations of propargyl-α-mannopyranoside were revisited, and products were analysed by NMR spectroscopy. The preparations were shown to yield by-products that have not been described in the literature yet. Our experiments showed that one-step procedures could not provide pure propargyl-α-mannopyranoside, while a three-step procedure yielded the desired compound of high purity.

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Section: Resultsmentioning

confidence: 99%

Selectivity of 1-O-Propargyl-d-Mannose Preparations

2022

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ChemInform Abstract: CARBOHYDRATES CONTAINING THE 2,6‐DIOXABICYCLO(3.3.0)OCTANE SKELETON: 3,6‐ANHYDROHEXOFURANOSE DERIVATIVES WITH D‐GLUCO, D‐MANNO, L‐IDO, AND L‐GULO CONFIGURATION

Koell¹,

Komander²,

Meyer³

1983

Chemischer Informationsdienst

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Selektive Tosylierungen an 3,6‐Anhydrohexofuranosiden mit gluco‐, manno‐ und gulo‐Konfiguration

Köll

Komander

1983

Liebigs Ann. Chem.

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Selektive Monotosylierung von Methyl-3,6-anhydro-a-~-mannofuranosid (1 a) ergibt bevorzugt das 5-0-Tosylat le, das durch nucleophile Substitution unter Inversion an C-5 den Zugang zu den Derivaten 2 mit p-L-gulo-Konfiguration erlaubt. Auch die Umsetzung des Ditosylates 1 b rnit Kaliumacetat in Dimethylformamid fuhrt ausschliel3Iich in die I -gulo-Reihe. Eine Substitution an C-2 wird nicht beobachtet. Das p-rnanno-Derivat 3a hingegen wird bevorzugt in 2-Stellung zu 3c tosyliert, das nur bei extrem langen Reaktionszeiten durch nucleophile Substitution in die gluco-Reihe ubergefuhrt werden kann. Die erwunschte Uberfuhrung auch der p-rnanno-Derivate 3 in die a-L-gulo-Reihe 4 gelingt uber das Ditosylat 3b, das bevorzugt in 5-Stellung unter Inversion der Konfiguration zu 4c substituiert werden kann. Zum besseren Verstandnis der unterschiedlichen Selektivitaten bei l a und 3a wurde auch die Monotosylierung von Za, 5 s und 6a mit p-L-gulosowie p-und a-D-gluco-Konfiguration untersucht. Die Ergebnisse werden unter Berdcksichtigung sterischer und polarer Faktoren interpretiert. Selective Tosylations of 3,6-Anhydrohexofuranosides with gluco, manno, andgufo ConfigurationSelective monotosylation of methyl 3,6-anhydro-a-o-mannofuranoside (1 a) preferentially yields the 5-0-tosylate l e which opens via nucleophilic substitution access to p-L-gulo derivatives 2 by inversion of configuration at C-5. Analogously reaction of the ditosylate 1 b with potassium acetate in dirnethylformamide gives L-gulo compounds exclusively. Substitution at C-2 is not observed. Contrary to this, the p-manno derivative 3 a is selectively tosylated at 2-position to give 3c which is transformed only after very long reaction times into the gluco series by nucleophilic substitution. Desired conversion of p-rnanno compounds 3 into a-L-gulu derivatives 4 is achieved only riia the ditosylate 3 b which is preferentially substituted by inversion of configuration at position 5 yielding 4c. Further insight into the different behaviour of l a and 3 a was gained by equal nionotosylation of Za, Sa, and 6a with P-L-gulo and p-and a-o-gluco configuration, respectively.The obtained results are rationalized by considering steric as well as polar effects.Glucose und Mannose lassen sich in wenigen Schritten in 3,6-Anhydride iiberfuhren'92'. Dieser Weg ware im Falle der entsprechenden Anhydride mit ido-und guloKonfiguration prinzipiell auch moglich, aber erheblich aufwendiger. Hier bietet sich Inversion der Konfiguration an C-5 in erstgenannten Verbindungen an. Man gelangt dann zwar in die L-Reihe, was aber fur viele Untersuchungen ohne Belang ist. Die L-idO-Isomeren sind so leicht uber 5-0-Sulfonyloxyderivate der 3,6-Anhydro-l,2-0-

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Kohlenhydrate mit 2,6‐Dioxabicyclo[3.3.0]octan‐Gerüst: Vergleichende Untersuchung von 3,6‐Anhydrohexofuranosederivaten mit D‐gluco‐, D‐manno‐, L‐ido‐ und L‐gulo‐Konfiguration

Cited by 19 publications

References 47 publications

Selectivity of 1-O-Propargyl-d-Mannose Preparations

Selectivity of 1-O-Propargyl-d-Mannose Preparations

ChemInform Abstract: CARBOHYDRATES CONTAINING THE 2,6‐DIOXABICYCLO(3.3.0)OCTANE SKELETON: 3,6‐ANHYDROHEXOFURANOSE DERIVATIVES WITH D‐GLUCO, D‐MANNO, L‐IDO, AND L‐GULO CONFIGURATION

Selektive Tosylierungen an 3,6‐Anhydrohexofuranosiden mit gluco‐, manno‐ und gulo‐Konfiguration

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