Dinuclear Copper(I) Thiodiacetate Complex-Mediated Expeditious Synthesis of the Chlorine-Containing Cyclen-Cored 36-Glucose-Coated Glycodendrimer

High-sugar-tethered glycodendrimers are a remarkable tool in glycobiology for the investigation of carbohydrate-protein interaction using its multivalency property. An enthralling double-stage convergent synthetic approach was selected to build a novel class of chlorine-containing glucose-coated dendrimers using an efficient click catalyst ‘dinuclear copper(I) thiodiacetate complex.’ In this context, cyclen core was developed through a divergent approach, while the glucodendron was developed via a convergent approach independently. Both azide-alkyne partners were coupled through a modular copper azide-alkyne cycloaddition (CuAAC) strategy to afford a high yield of the desired 36-glucose-coated glycodendrimer. The synthesized glycodendrimer has been elucidated by NMR, gel permeation chromatography (GPC), and IR spectral analysis.

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Fractionation of lignosulphonates released during the early stages of delignification

Canadian Journal of Chemistry ◽

10.1139/v83-074 ◽

1983 ◽

Vol 61 (2) ◽

pp. 416-420 ◽

Cited By ~ 8

Author(s):

Norman G. Lewis ◽

David A. I. Goring ◽

Alfred Wong

Keyword(s):

Molecular Weight ◽

High Performance ◽

Black Spruce ◽

Gel Permeation Chromatography ◽

Bimodal Distribution ◽

High Yield ◽

Low Molecular Weight ◽

Lower Yield ◽

Spruce Wood ◽

Gel Permeation

High-yield spent bisulphite liquor (HY-SBL) from sulphonated black spruce wood (Piceamariana) was fractionated by gel permeation chromatography (GPC) and by high-performance liquid chromatography (HPLC). The GPC fractionation gave a wide bimodal distribution, whereas with HPLC, a more detailed resolution was seen with the bulk of the fraction giving several clearly defined peaks. The paucidisperse material was further concentrated by a bulk fractionation of the crude SBL which included complexing the lignosulphonates with dicyclohexylamine. The isolated paucidisperse material was found to be dialyzable and to constitute 90% of the lignosulphonate in the sample of SBL. If the bisulphite pulp obtained was recooked in fresh acid sulphite liquor to a lower yield, most of the lignosulphonate dissolved was widely polydisperse with no indication of the discrete components resolvable by HPLC. However, 25% of the lignin made soluble was in the form of the paucidisperse fractions. In all, we were able to obtain about 50% of the lignin in spruce wood as a relatively low molecular weight lignosulphonate resolvable into discrete fractions by HPLC.

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Examination of dye–protein interaction by gel-permeation chromatography

Biomedical Chromatography ◽

10.1002/bmc.552 ◽

2006 ◽

Vol 20 (2) ◽

pp. 195-199 ◽

Cited By ~ 9

Author(s):

Jolanta Sereikaite ◽

Vladas-Algirdas Bumelis

Keyword(s):

Protein Interaction ◽

Gel Permeation Chromatography ◽

Gel Permeation

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A New Method for Synthesis of Poly(2,6-dimethyl-1,4-phenylene oxide) and Poly(2,6-diphenyl-1,4-phenyl oxide)

Journal of Chemistry ◽

10.1155/2013/856928 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4

Author(s):

Naser M. Al Andis

Keyword(s):

Differential Scanning Calorimetry ◽

Nmr Spectroscopy ◽

Microwave Heating ◽

Molar Mass ◽

Gel Permeation Chromatography ◽

High Yield ◽

Scanning Calorimetry ◽

Phenylene Oxide ◽

Gel Permeation ◽

Amine Complex

The polymerization of two monomers 2,6-dimethylphenol and 2,6-diphenylphenol was carried out by an oxidative route in the presence of Cu(I) as a catalyst and amine complex as a solvent assisted by microwave heating. The synthesized polymers were characterized by NMR spectroscopy, differential scanning calorimetry (DSC), and gel permeation chromatography (GPC). It was observed that this process of polymerization gives high yield (98 wt%) of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) and poly(2,6-diphenyl-1,4-phenylene oxide) (PPPO) with a molar mass of 1180 (M¯n), 1400 (M¯w) and 28000 (M¯n), 46500 (M¯w) gm/mol, respectively. A negligible amount of diphenoquinone was also observed and its dispersity was rather moderate, 1.17 and 1.68, respectively.

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Aggregated, Conformationally Changed Fibrinogen Exposes the Stimulating Sites for t-PA-Catalysed Plasminogen Activation

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650269 ◽

1996 ◽

Vol 75 (02) ◽

pp. 326-331 ◽

Cited By ~ 7

Author(s):

Unni Haddeland ◽

Knut Sletten ◽

Anne Bennick ◽

Willem Nieuwenhuizen ◽

Frank Brosstad

Keyword(s):

Conformational Changes ◽

Gel Permeation Chromatography ◽

Tissue Type ◽

Plasminogen Activation ◽

Chromogenic Substrate ◽

Type Plasminogen Activator ◽

Gel Permeation ◽

Self Association ◽

Fibrin Monomers ◽

Stimulation Of

SummaryThe present paper shows that conformationally changed fibrinogen can expose the sites Aα-(148-160) and γ-(312-324) involved in stimulation of the tissue-type plasminogen activator (t-PA)-catalysed plasminogen activation. The exposure of the stimulating sites was determined by ELISA using mABs directed to these sites, and was shown to coincide with stimulation of t-PA-catalysed plasminogen activation as assessed in an assay using a chromogenic substrate for plasmin. Gel permeation chromatography of fibrinogen conformationally changed by heat (46.5° C for 25 min) demonstrated the presence of both aggregated and monomeric fibrinogen. The aggregated fibrinogen, but not the monomeric fibrinogen, had exposed the epitopes Aα-(148-160) and γ-(312-324) involved in t-PA-stimulation. Fibrinogen subjected to heat in the presence of 3 mM of the tetrapeptide GPRP neither aggregates nor exposes the rate-enhancing sites. Thus, aggregation and exposure of t-PA-stimulating sites in fibrinogen seem to be related phenomena, and it is tempting to believe that the exposure of stimulating sites is a consequence of the conformational changes that occur during aggregation, or self-association. Fibrin monomers kept in a monomeric state by a final GPRP concentration of 3 mM do not expose the epitopes Aα-(148-160) and γ-(312-324) involved in t-PA-stimulation, whereas dilution of GPRP to a concentration that is no longer anti-polymerizing, results in exposure of these sites. Consequently, the exposure of t-PA-stimulating sites in fibrin as well is due to the conformational changes that occur during selfassociation.

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