Publications related to Structural isomer

Carboxylic acid isomer-directed synthesis of CdS nanocluster isomers

Selective synthesis of nanocluster (NC) isomers with tailored structures holds significant importance for enhancing their applications. Here, we develop an effective strategy for the selective synthesis of CdS NC isomers through the judicious choice of a p ...

Royal Soc Chemistry2024

Identification of N-glycan positional isomers by combining IMS and vibrational fingerprinting of structurally determinant CID fragments

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

While glycans are present on the surface of cells in all living organisms and play key roles in most biological processes, their isomeric complexity makes their structural characterization challenging. Of particular importance are positional isomers, for w ...

ROYAL SOC CHEMISTRY2022

Acid-base-induced fac → mer isomerization of luminescent iridium(iii) complexes

Kay Severin, Farzaneh Fadaei Tirani, Albert Ruggi, Anastasia Gitlina, Carolina Luciana Plaice

Luminescent Ir(C^N)3 complexes (C^N = cyclometalated arylpyridine ligand) exist in the form of two stable isomers with distinct photophysical and electrochemical properties: fac and mer. Herein, we show that fac-Ir(C^N)3 complexes can be converted into the ...

2022

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

Mechanistic Insight into Supramolecular Polymerization in Water Tunable by Molecular Geometry

Lukas Pfeifer

Supramolecular self-assembly in water based on non-covalent bonding is attracting major attention due to the potential of hydrogels and aqueous polymers in biomedical applications. Although supramolecular polymerization in organic solvents is well establis ...

CHINESE 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

A new approach for identifying positional isomers of glycans cleaved from monoclonal antibodies

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

Glycosylation patterns in monoclonal antibodies (mAbs) can vary significantly between different host cell types, and these differences may affect mAbs safety, efficacy, and immunogenicity. Recent studies have demonstrated that glycan isomers with the termi ...

2021

Natural Product Synthesis Enabled by Domino Processes Incorporating a 1,2-Rearrangement Step

Qian Wang, Jieping Zhu, Bastien Delayre

The art of natural product total synthesis is closely associated with two major determinants: the development/application of novel chemical reactions and the innovation in strategic use of classic organic reactions. While purposely seeking/applying a new s ...

2021

Photoisomerization of Linear and Stacked Isomers of a Charged Styryl Dye: A Tandem Ion Mobility Study

Eduardo Carrascosa Casado

The photoisomerization behavior of styryl 9M, a common dye used in material sciences, is investigated using tandem ion mobility spectrometry (IMS) coupled with laser spectroscopy. Styryl 9M has two alkene linkages, potentially allowing for four geometric i ...

AMER CHEMICAL SOC2021

Action spectroscopy of deprotomer-selected hydroxycinnamate anions

Eduardo Carrascosa Casado

Tandem ion mobility mass spectrometry-coupled laser excitation is used to record photodetachment, photoisomerization and photodepletion action spectra for a series of deprotomer-selected hydroxycinnamate anions, including deprotonated caffeic, ferulic and ...

SPRINGER2021

Tuning the Thermal Stability and Photoisomerization of Azoheteroarenes through Macrocycle Strain**

Anne-Clémence Corminboeuf, Alan Scheidegger, Sergio Vela Llausi, Raimon Fabregat I De Aguilar-Amat

Azobenzene and its derivatives are one of the most widespread molecular scaffolds used in a range of modern applications, as well as in fundamental research. After photoexcitation, azo-based photoswitches revert back to the most stable isomer on a timescal ...

WILEY-V C H VERLAG GMBH2021

Cryogenic Infrared Action Spectroscopy Fingerprints the Hydrogen Bonding Network in Gas-Phase Coumarin Cations

Thomas Rizzo, Eduardo Carrascosa Casado, Robert Paul Pellegrinelli

We report cryogenic vibrational spectra of gas-phase cations of two common hydroxycoumarins, scopoletin and esculetin, as well as their glycosidic derivatives, scopolin and esculin. The study allows direct observation of the intramolecular interactions bet ...

2020

Quantifying Fano properties in self-assembled metamaterials

Olivier Martin

Fano resonances in metamaterials can be explained by the coupling between different modes sustained by the meta-atom. While the associated spectral features are usually quite easy to identify for top-down metamaterials, thanks to the deterministic arrangem ...

2019

Combining ultra-high resolution ion-mobility spectrometry with cryogenic IR spectroscopy for the study of biomolecular ions

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Robert Paul Pellegrinelli, Natalia Yalovenko

Double-resonance spectroscopic schemes in combination with cryogenic ion traps are the go-to techniques when isomer-specific high-resolution spectra are required for analysis of molecular ions. Their limitation lies in the requirement for well-resolved, is ...

2019

Separation and Identification of Glycan Anomers Using Ultrahigh-Resolution Ion Mobility Spectrometry and Cryogenic Ion Spectroscopy

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Valeriu Scutelnic

The analysis of carbohydrates, or glycans, is challenging for established structure-sensitive gas-phase methods. The multitude of possible stereo-, regio- and structural isomers make them substantially more complex to ana-lyze than DNA or proteins, and no ...

2019

Versatile coordination of acetazolamide to ruthenium(ii) p-cymene complexes and preliminary cytotoxicity studies

Paul Joseph Dyson, Lucinda Kate Batchelor

The carbonic anhydrase inhibitor acetazolamide (AcmH2) reacted with [(η6-p-cymene)RuCl(μ-Cl)]2 to afford [(η6-p-cymene)RuCl2(κN-AcmH2)], 1A, in near-quantitative yield. In methanol, 1A exists in equilibrium with 1B, being probably a coordination isomer, as ...

2018

Intense fluorescence of Au-20

Harald Brune, Wolfgang Harbich, Chongqi Yu

Ligand-protected Au clusters are non-bleaching fluorescence markers in bio- and medical applications. Here we show that their fluorescence can be an intrinsic property of the Au cluster itself. We find a very intense and sharp fluorescence peak located at ...

American Institute of Physics2017

A Decapeptide Hydrated by Two Waters: Conformers Determined by Theory and Validated by Cold Ion Spectroscopy

Natalia Nagornova, Oleg Boyarkine, Robert Benny Gerber

The intrinsic structures of biomolecules in the gas phase may not reflect their native solution geometries. Microsolvation of the molecules bridges the two environments, enabling a tracking of molecular structural changes upon hydration at the atomistic le ...

American Chemical Society2017

A systematic approach for thermal stability predictions of chemicals and their risk assessment: Pattern recognition and compounds classification based on thermal decomposition curves

Thierry Meyer, Nadia Baati, Annik Nanchen, Laetitia Mage

In the context of process and product design, predictive models are increasingly employed. Decomposition properties of chemicals may be experimentally determined through calorimetric measurements, and a few molecular structure-based models- which correlate ...

Institution of Chemical Engineers2017

A Spotlight on the Compatibility between XFEL and Ab Initio Structures of the Oxygen Evolving Complex in Photosystem II

Daniele Narzi, Leonardo Guidoni

The Mn4CaO5 cluster of photosystem II promotes a crucial step in the oxygenic photosynthesis, namely, the water-splitting reaction. The structure of such cluster in the S-1 state of the Kok-Joliot's cycle has been recently resolved by femtosecond X-ray fre ...

Wiley-V C H Verlag Gmbh2017