Publications associées à Liaison osidique

Visualizing Chiral Interactions in Carbohydrates Adsorbed on Au(111) by High-Resolution STM Imaging

Klaus Kern, Uta Schlickum, Stephan Rauschenbach

Carbohydrates are the most abundant organic material on Earth and the structural "material of choice" in many living systems. Nevertheless, design and engineering of synthetic carbohydrate materials presently lag behind that for protein and nucleic acids. ...

Wiley-VCH Verlag GmbH2023

Multistage Ion Mobility Spectrometry Combined with Infrared Spectroscopy for Glycan Analysis

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Priyanka Bansal

The structural complexity of glycans makes their characterization challenging, not only because of the presence of various isomeric forms of the precursor molecule but also because the fragments can themselves be isomeric. We have recently developed an IMS ...

2023

Combining multi-stage ion mobility spectrometry with cryogenic infrared spectroscopy for glycan analysis

Priyanka Bansal

Structural analysis of biomolecules is essential to understanding biological processes. Among the various classes of biomolecules, glycans have gained significant attention recently due to their ubiquitous roles in biological systems. However, study of gly ...

EPFL2022

Identification of Mobility-Resolved N-Glycan Isomers

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Priyanka Bansal, Robert Paul Pellegrinelli

Glycan analysis has evolved considerably during the last decade. The advent of high-resolution ion-mobility spectrometry has enabled the separation of isomers with only the slightest of structural differences. However, the ability to separate such species ...

AMER CHEMICAL SOC2022

A New Strategy Coupling Ion-Mobility-Selective CID and Cryogenic IR Spectroscopy to Identify Glycan Anomers

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Eduardo Carrascosa Casado, Priyanka Bansal, Robert Paul Pellegrinelli, Lei Yue

Determining the primary structure of glycans remains challenging due to their isomeric complexity. While high-resolution ion mobility spectrometry (IMS) has recently allowed distinguishing between many glycan isomers, the arrival-time distributions (ATDs) ...

2022

Combining cryognic ion spectroscopy with ion mobility for the study of glycan fragmentation

Robert Paul Pellegrinelli

The importance of glycans in biological processes are matched by their structural complexity. Coating the surface of most living cells, glycans play key roles in many biological processes, and the role they play is closely related to their structures. Stru ...

EPFL2021

Revealing Single-Bond Anomeric Selectivity in Carbohydrate-Protein Interactions

Oleg Boyarkine, Ruslan Yamaletdinov, Aleksandr Pereverzev, Viktoriia Aladinskaia

The noncovalent binding of proteins to glycans is amazingly selective to the isoforms of carbohydrates, including alpha/beta anomers that coexist in solution. We isolate in the gas phase and study at the atomic level the simplest model system: noncovalent ...

AMER CHEMICAL SOC2020

Copper-Catalyzed Cyanoalkylative Aziridination of N-Sulfonyl Allylamines

Qian Wang, Jieping Zhu, Minh Tu Ha, Weisi Guo

Reaction of N-arylsulfonyl allylamines with alkyl nitriles in the presence of di-tert-butyl peroxide (DTBP) and a catalytic amount of copper salt afforded homologated aziridines in 43-86% yield. A sequence involving addition of the in situ generated cyanom ...

Wiley2020

Using SLIM-Based IMS-IMS Together with Cryogenic Infrared Spectroscopy for Glycan Analysis

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Priyanka Bansal, Ali H Abikhodr, Vasyl Yatsyna, Natalia Yalovenko

The isomeric heterogeneity of glycans poses a great challenge for their analysis. While combining ion mobility spectrometry (IMS) with tandem mass spectrometry is a powerful means for identifying and characterizing glycans, it has difficulty distinguishing ...

2020

Cryogenic Ion Spectroscopy for Identification of Monosaccharide Anomers

Thomas Rizzo, Valeriu Scutelnic

We combine conformer-selective, cryogenic infrared spectroscopy, quantum mechanical computations, and 18O substitution at the reducing end to determine the structural preferences of protonated glucosamine in the gas phase. Cryogenic infrared-infrared (IR-I ...

2019

Carbohydrate stabilization extends the kinetic limits of chemical polysaccharide depolymerization

Jeremy Luterbacher, Masoud Talebi Amiri, Ydna Marie Questell-Santiago, Raquel Zambrano Varela

Polysaccharide depolymerization is an essential step for valorizing lignocellulosic biomass. In inexpensive systems such as pure water or dilute acid mixtures, carbohydrate monomer degradation rates exceed hemicellulose—and especially cellulose—depolymeriz ...

2018

Cryogenic Vibrational Spectroscopy Provides Unique Fingerprints for Glycan Identification

Thomas Rizzo, Michael Zachary Kamrath, Chiara Masellis, Neelam Khanal

The structural characterization of glycans by mass spectrometry is particularly challenging. This is because of the high degree of isomerism in which glycans of the same mass can differ in their stereochemistry, attachment points, and degree of branching. ...

2017

Strain-Promoted C-C Bond Cleavages of Cyclobutanes : A Molecular Complexity Generating Tool

Laetitia Marie Mélanie Souillart

The catalytic activation of carbon-carbon single bonds is a major challenge in organometallic chemistry, since the lack of prefunctionalization steps opens the way to new, economically and ecologically attractive reaction pathways. Strained ring substrates ...

EPFL2015

Toward Quantitative Measurements of Enzyme Kinetics by Dissolution Dynamic Nuclear Polarization

Geoffrey Bodenhausen, Aurélien Bornet, Sami Jannin, Jonas Milani, Daniel Abergel

Dissolution dynamic nuclear polarization (D-DNP) experiments enabled us to study the kinetics of the enzymatic phosphorylation reaction of glucose to form glucose-6-phosphate (G6P) by hexokinase (HK), with or without the presence of an excess of G6P, which ...

2014

Synthesis of C-linked Disaccharides and Analogues as Biomimetics of the TF Epitope

Maria Kolympadi

Glycoproteins and glycolipids are major components of the outer surface of mammalian cells. Their carbohydrate moieties, which are directed into the outer environment, serve as ligands for receptor proteins, such as lectins, pathogen proteins and antibodie ...

EPFL2011

Synthesis of Glycomimetics as Potential Anti-Cancer Agents

Annabelle Gillig

Cancer cells exhibit different properties that make them dangerous to the host, such as the ability to invade other tissues and the abnormal response to the control mechanisms that regulate the division of normal cells, which allow them to divide in a rela ...

EPFL2010

Recent Synthetic Approaches Toward Non-anomeric Spiroketals in Natural Products

Pierre Vogel, Sandrine Gerber, Sylvain Favre

Many natural products of biological interest contain [6,5]- and [6,6]-spiroketal moieties that can adopt various configurations, benefiting or not from anomeric conformation stabilizing effects. The spiroketal fragments are often important for the biologic ...

2008

One-Step Conversion of Cellobiose to C6-Alcohols Using a Ruthenium Nanocluster Catalyst

Paul Joseph Dyson, Ning Yan, Cheng Zhao, Huizhen Liu

The one-step conversion of cellulose to C6-alcs. via green and energy efficient approaches has, as far as we are aware, not been reported. Such a process presents a considerable challenge, the two key problems being (1) finding a suitable solvent that diss ...

2006

Synthesis of C-glycosides and C-linked disaccharides through carbonylative Stille coupling reactions

Peter Steunenberg

In the first part, we described the synthesis of C-(1'→1) and C-(1'→4) disaccharide precursors, which are readily obtained via the carbonylative Stille coupling of glucal and isolevoglucosenone derivatives. Tin glycals and triflates, derived from isolevogl ...

EPFL2005

Synthesis of 2'-O-[(triisopropylsilyl)oxy]methyl(=tom)-protected ribonucleoside phosphoramidites containing various nucleobase analogs

Sébastien Porcher

The first results of a study aiming at an efficient prepn. of a large variety of 2'-O-[(triisopropylsilyl)oxy]methyl(=tom)-protected ribonucleoside phosphoramidite building blocks contg. modified nucleobases are reported. All of the here presented nucleosi ...

Wiley-VHCA AG2005