Protonenresonanz‐Untersuchungen an Polysaccharid‐Derivaten

Friebolin, H.; Keilich, G.; Siefert, E.

doi:10.1002/ange.19690812018

Cited by 15 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…NMR spectrum of allylated and acetylated viscose. Peak assignment was achieved with [ 1 H,13 C]-HSQC and [ 1 H,13 C]-HMBC spectra shown inFigure 3and agrees with literature[22,23]. The peaks were assigned as follows: δ (ppm) = 1.89,1.94 and 2.00 (H-112,3, acetyl-CH3), 2.12 (H-116, acetyl-CH3), 3.52 (H5 on AGU), 3.71 (H4 on AGU), 3.85 (H-7, allyl H), 4.05 (H6' on AGU), 4.32 (H6 on AGU), 4.40 (H1 on AGU), 4.79 (H2 on AGU), 5.06 (H3 on AGU), 5.20 (H-9, allyl H), 5.33 (H-10, allyl H), 5.85 (H-8, allyl H2).…”

supporting

confidence: 81%

Determination of the xanthate group distribution on viscose by liquid-state 1H NMR spectroscopy

et al. 2010

View full text Add to dashboard Cite

An analytical method for determination of the xanthate group distribution on viscoses based on liquid-state NMR spectroscopy was developed. Sample preparation involves stabilization of the xanthate group by allylation followed by derivatization of the remaining free hydroxyl groups at the glucose unit. The method was applied for studying (1) the γ-value (number of xanthate groups per 100 glucose units) of viscose, (2) the distribution of the xanthate groups on the anhydroglucose unit (AGU), and (3) changes of the xanthate group distribution during ripening. Results of the γ-value determination are well comparable with reference methods. Elucidation of the xanthate group distribution on the AGU gives the percentage at the C-6 position and a cumulative share of the positions C-2 and C-3. During ripening, xanthate groups at C-2 and C-3 degrade first, while xanthates at C-6 decompose at a slower rate.

show abstract

supporting

confidence: 81%

Determination of the xanthate group distribution on viscose by liquid-state 1H NMR spectroscopy

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Aus der Literatur9-14) und aus eigenen Arbeiten") geht hervor, da8 noch keine ahnlich gesicherten GesetzmaDigkeiten abgeleitet werden konnen, wie es uns bei den Untersuchungen an den Polysacchariden mittels 'H-NMR-Spektroskopie gelang'. [4][5][6][7]. So ist u. a. noch unbekannt, ob und wie die Kettenlange die Resonanzfrequenzen aller C-Atome einer polymerhomologen Reihe von Kohlenhydraten beeinfluljt undim Falle einer Abhangigkeit welcher Zusammenhang mit strukturellen Parametern besteht.…”

unclassified

C‐13‐NMR‐spektroskopische untersuchungen an polymerhomologen reihen von α,1→6‐ und α,1→4‐glucanen

et al. 1976

View full text Add to dashboard Cite

Eingangsdatum: 10. Juni 1975) ZUSAMMENFASSUNG :Die 3C-NMR-Spektren von polymerhomologen Reihen der Malto-und Isomaltooligosaccharide, sowie die von Amylose und Dextran wurden aufgenommen und analysiert. Dabei wurde festgestellt, daI3 bei den Polymerhomologen die Resonanzen der C-Atome der mittelstandigen Glucoseeinheiten unabhangig von der Kettenlange sind. Wahrend sich das Polysaccharid Dextran wie die Oligosaccharide verhalt, zeigen im Falle der Amylose die Resonanzen der C-Atome 1 und 4 Abweichungen von 0,4 bzw. 0,5ppm. Diese-wenn auch kleinen -Effekte geben moglicherweise einen Hinweis auf das Vorliegen einer Uberstruktur in Losung. SUMMARY:The 3C-NMR spectra of malto-and isomalto-oligosaccharides, amylose and dextrane were analysed. It was observed that in both series of oligosaccharides and polysaccharides the resonances of the central glucose units are independent of the chain length with the exception of the C-atoms 1 and 4 of amylose which show deviations of 0,4 and 0,s ppm. These small effects can possibly be explained by a definite polysaccharide chain conformation in solution.

show abstract

“…A particularly valuable method in identifying polysaccharides is nuclear magnetic resonance spectroscopy (19) . When benzoyl or acetyl derivatives of polysaccharides are studied by this method, they exhibit proton signals highly characteristic for the kind of sugar present as well as for the special type of linkage .…”

Section: Chemistrymentioning

confidence: 99%

“…Both spectra are virtually identical, but they differ from comparative spectra of the benzoyl derivatives of other polysaccharides, e .g. amylose, pullulan, and mannan (19) .…”

Section: Chemistrymentioning

confidence: 99%

Scale Formation in Chrysophycean Algae

Brown

Franke

Kleinig

et al. 1970

The Journal of Cell Biology

135

View full text Add to dashboard Cite

The cell wall of the marine chrysophycean alga Pleurochrysis scherfellii is composed of distinct wall fragments embedded in a gelatinous mass . The latter is a polysaccharide of pectic character which is rich in galactose and ribose . These wall fragments are identified as scales . They have been isolated and purified from the vegetative mother cell walls after zoospore formation . Their ultrastructure is described in an electron microscope study combining sectioning, freeze-etch, and negative staining techniques. The scales consist of a layer of concentrically arranged microfibrils (ribbons with cross-sections of 12 to 25 X 25 to 40 A) and underlying radial fibrils of similar dimensions . Such a network-plate is densely coated with particles which are assumed to be identical to the pectic component . The microfibrils are resistant to strong alkaline treatment and have been identified as cellulose by different methods, including sugar analysis after total hydrolysis, proton resonance spectroscopical examination (NMR spectroscopy) of the benzoylated product, and diverse histochemical tests. The formation and secretion of the scales can be followed along the maturing Golgi cisternae starting from a pronounced dilated "polymerization center" as a completely intracisternal process which ends in the exocytotic extrusion of the scales . The scales reveal the very same ultrastructure within the Golgi cisternae as they do in the cell wall . The present finding represents the first evidence on cellulose formation by the Golgi apparatus and is discussed in relation to a basic scheme for cellulose synthesis in plant cells in general .

show abstract

Protonenresonanz‐Untersuchungen an Polysaccharid‐Derivaten

Cited by 15 publications

References 0 publications

Determination of the xanthate group distribution on viscose by liquid-state 1H NMR spectroscopy

Determination of the xanthate group distribution on viscose by liquid-state 1H NMR spectroscopy

C‐13‐NMR‐spektroskopische untersuchungen an polymerhomologen reihen von α,1→6‐ und α,1→4‐glucanen

Scale Formation in Chrysophycean Algae

Contact Info

Product

Resources

About