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Escins constitute an abundant family of saponins (saponosides) and are the most active components in Aesculum hippocastanum (horse chestnut—HC) seeds. They are of great pharmaceutical interest as a short-term treatment for venous insufficiency. ...

In this work, a simple, fast (10 min) and environmentally friendly extraction method using deep eutectic solvents (DES), based on choline chloride and glycerol, was established to extract saponins from five quinoa samples...

In this work, we tested the impacts of sunflower phenolamides on healthy and parasite infected buff-tailed bumble bees. Expectedly, sunflower pollen had harmful consequences on bumble bee development but surprisingly, it did not alter parasite load. By contrast, sunflower phenolamides had milder effects on bumble bee development but unexpectedly increased parasite load.

Saponins are specific metabolites abundantly present in plants and several marine animals. Their high cytotoxicity is associated with their membranolytic properties, i.e., their propensity to disrupt cell membranes upon incorporation. ...

On Wednesday February 9, Fabrice SAINTMONT has defended his PhD thesis entitled “Synthetic macromolecules and nucleic acids : experimental and theoretical investigation of dendriplex structures”

Although N-(S)-phenylethyl peptoids are known to adopt helical structures in solutions, the corresponding positively charged ions lose their helical structure during the transfer from the solution to the gas phase due to the so-called charge solvation effect. We, here...

Saponins are plant and marine animal specific metabolites that are commonly considered as molecular vectors for chemical defenses against unicellular and pluricellular organisms. Their toxicity is attributed to their membranolytic properties. Modifying the molecular structures of saponins...

An increasing number of studies take advantage of ion mobility spectrometry (IMS) coupled to mass spectrometry (IMS-MS) to investigate the spatial structure of gaseous ions. Synthetic polymers occupy a unique place in the field of IMS-MS. Indeed...

On Tuesday October 26, Gaela CAUCHIE has defended her PhD thesis entitled “Profilage chimique de la biomasse microalgale par MS et RMN : étude de cas avec Microchloropsis gaditana ” at the Université de Reims Champagne-Ardenne. The thesis was co-directed by Prof Jean-Hugues Renault (URCA) and Prof Pascal Gerbaux (UMONS) in the frame of the ALPO project granted by the Interreg program.

On Friday September 24, Sébastien HOYAS has defended his PhD thesis entitled “Characterization and exploitation of peptoid secondary structures: a synergetic experimental and computational approach ” at the University of Mons.

Pseudomonas aeruginosa (P.A.) is a human pathogen belonging to the top priorities for the discovery of new therapeutic solutions. Its propensity to generate biofilms strongly complicates the treatments required to cure P.A. infections. Herein, we describe the synthesis of a series of novel rotaxanes composed of a central galactosylated pillar[5]arene, a tetrafucosylated dendron, and a tetraguanidinium subunit. Besides the high affinity of the final glycorotaxanes for the two P.A. ...

Saponins are amphiphilic molecules of pharmaceutical interest and most of their biological activities (i.e., cytotoxic, hemolytic, fungicide, etc.) are associated to their membranolytic properties. These molecules are secondary metabolites present in numerous plants and in some marine animals...

In this paper, we benefit from the expertise of Prof. Luca Muccioli in the modeling of self-assembly monolayers to study the interaction between peptoids and chiral guests. Indeed, peptoids can act as chiral selectors depending on the choice of the side chain.

We recently reported a joint experimental and theoretical study of peptoid ions bearing (S)-N-1-phenylethyl side chains. In this study, we demonstrated that the gas phase conformation, probed by ion mobility mass spectrometry, was different from the solution phase conformation (loop vs. helix) because the charge, mandatory for mass spectrometry analysis, must be stabilized and causes the backbone to wrap around to maximize the ion-dipole interactions.

Liquid chromatography – mass spectrometry (LC-MS) experiments were used to qualitatively and semi-quantitatively monitor the impact of bead milling and the influence of the nature of the extraction solvents, Bligh and Dyer (B&D) versus n-heptane, on the composition of the structural lipids extracted from the microalgae Microchloropsis gaditana.

Recent advances in catalysis enriched the toolbox to prepare well-defined polyester materials such as polylactide (PLA). Herein, we report the use of crown ethers to speed up the polymerization of L-lactide (L-LA) initiated by an exogenous alcohol and catalyzed by potassium acetate (KOAc).

On Thursday march 11, Tiffani BOUANATI has defended her PhD thesis entitled “Production, characterization and valorization of the polysaccharidic fraction of  macroalgae and microalgae”.

On Friday October 30, Sébastien DELPIERRE has defended his PhD thesis entitled “Self-Healable and Recyclable Polymer Networks Based on Dynamic Covalent Boroxine Chemistry”.

In this work, we evaluate whether a relationship exists between the primary structures of synthetic homo and copolymers and their secondary structures as gaseous ions. IMS−MS experiments are further complemented by MD simulations.

On Friday September 25, Quentin DUEZ has defended his PhD thesis entitled “Gas-Phase Structure of Polymer Ions : Ionization, Relaxation, and Implications for Structural Characterization”.

On Friday September 18, Emmanuel Colson - Manu - has defended his PhD thesis entitled “Green Waste Valorization : tuning the biological properties of horse chestnut and quinoa husk saponins by molecular engineering”.

On Friday September 11, Romain Liénard, PhD student at the Organic Synthesis Lab (S²MOs) and Polymer Lab (SMPC), has defended his PhD thesis entitled “Original Cyclo-based Macrostructures: Elaboration and Characterization” under the joint supervision of Olivier Coulembier and Julien De Winter.

We report the synthesis, characterization and biological profile of new bis-triazoled cyclo-(polylactide)s functionalized with folic acid (c-PLA-FA) or rhodamine (c-PLA-Rhod), obtained by an optimized combination of ROP and “click” chemistry reactions.

Algae biomass is nowadays considered as a unique reservoir of a huge variety of different molecules, such as lipids, carbohydrates, proteins and secondary metabolites, awaiting development in various fields. In particular, the valorization of the algae polysaccharide content is still in its infancy and intense research activity is starting to appear.

The paper untitled “Enzymatic Polycondensation of 1,6-Hexanediol and Diethyl Adipate: A Statistical Approach Predicting the Key-Parameters in Solution and in Bulk" Discussed about enzymatic polycondensation of 1,6-hexanediol and diethyl adipate.

Following the GCB-CBB incentive award received by Julien De Winter during the last SRC meeting (Namur, October 2019), it has been requested to write a mini review for “Chimie Nouvelle”.

In this paper, we study the structure of different generations and charge states of PAMAM and PPI dendrimers in the gas phase by Ion Mobility Spectrometry and Molecular Dynamics.

Excessive pollen harvesting by bees can compromise the reproductive success of plants. Plants have therefore evolved different morphological structures and floral cues to narrow the spectrum of pollen feeding visitors.

We are proud to announce the acceptance of our second review about cyclic polymers, which will be published in Journal of Polymer Science Part A: Polymer Chemistry. Cyclic polymers have been considered a hot topic for over two decades now. ...

In this paper, we are interested to Chenopodium quinoa seed, a staple food widely used around the world due to high nutritive values and the resistance of the crop to drought, cold and hard climate. However, the husk represents a waste that contains huge amounts of saponins that certainly deserve valorization. ...

In the present study, we use this approach to investigate the release of polylactide (PLA) ions from water/acetonitrile ESI droplets. We found that cationized gaseous PLA ions can be formed via various competing pathways. Some MD runs showed extrusion and subsequent separation of polymer chains from the droplet, as envisioned by the chain ejection model (CEM). ...

We demonstrate with the help of theoretical modelling that peptoids actually adopt a loop-like geometry in the gas phase even though the measured collision cross sections are very similar to those expected for helices. ...

New just accepted paper in Polymers “Reactive Extrusion and Magnesium (II) N-Heterocyclic Carbene Catalyst in Continuous PLA Production” ...

On Friday November 29, Emilie Halin has defended her PhD thesis entitled “On the Mass Spectrometry Characterization of peptoids, a new class of biomimetic synthetic polymers with tunable secondary structures”.

In this work, we are investigating the suitability of Ion Mobility Spectrometry-Mass Spectrometry (IMS) for the quantification of two isomers. A cyclic poly(L-lactide) is prepared through photodimerization of its linear homologue. ...

in the present work, the controlled radical homopolymerization of ethylene via organometallic-mediated radical polymerization (OMRP) using a cobalt complex as controlling agent was investigated. For the first time, block copolymers composed of ethylene and polar vinyl monomers, e.g. poly(vinyl acetate)-b-polyethylene (PVAc-b-PE) and poly(ethylene vinyl acetate)-b-polyethylene (EVA-b-PE) were prepared. ...

In this article we investigate association of the Ni-catalyst during Kumada catalyst transfer condensative polymerization (KCTCP) and hypothesize that when adding a para-phenylene monomer to a living thiophene block to synthesize poly(thiophene)-b-poly(para-phenylene), an equilibrium exist between the incorporation of the para-phenylene monomer and the trapping of the Ni-catalyst by association with the thiophene block. ...

In the present paper, it has been shown that ion mobility experiments together with liquid chromatography separation can be utilized for the structural characterization of stereoisomeric and regioisomeric saponins. Saponins presenting isomeric side chains, such as tiglic and angelic acid residues, can be distinguished by recording the Arrival Time Distributions (ATD), provided that high resolution ion mobility separation is used. ...

Voici un petit souvenir du BBQ 2019

Echinoderms form a remarkable phylum of marine invertebrates that present specific chemical signatures unique in the animal kingdom. It is particularly the case for essential triterpenoids that evolved separately in each of the five echinoderm classes.

A novel class of star-shaped multi-azobenzene photoswitches comprising individual photochromes connected to a central trisubstituted 1,3,5-benzene core is reported. ...

Several families of polymers possessing various end-groups are characterized by ion mobility mass spectrometry (IMMS). A significant contribution of the end-groups to the ion collision cross section (CCS) is observed, although their role is neglected in current fitting models described in literature. ...

A poly(3-hexylthiophene)-block-perfluoropolyether-block-poly(3-hexylthiophene) (P3HT-b-PFPE-b-P3HT) triblock copolymer was synthesized by copper(I)-catalyzed alkyne–azide cycloaddition. The copolymer was unequivocally characterized by size exclusion chromatography, mass spectrometry and nuclear magnetic resonance (NMR). ...

End-functionalized poly(3-hexylthiophene) (P3HT) and poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA) were synthesized using controlled polymerization techniques and linked together to lead to a diblock copolymer structure via click cycloaddition.

The 12th Meeting of the Young Chemists of the Royal Society of Chemistry took place on April 26th in Brussels. During this meeting, Irène Semay (S²MOs – Center on the picture) and Quentin Duez (S²MOs/CMN – Left on the picture) were respectively awarded of the Best Poster Prize and the Jean-Claude Braekman Prize for the best oral communication describing his collaboration with a foreign lab!

Here, we report the synthesis of a novel diester bearing a pendant lactam unit from methyl levulinate and aspartic acid. The palladiumcatalyzed reductive amination/cyclization sequence was carefully optimized to afford the diacid with high yield (>95 %).

A paper entitled “Identification of 4-Hydroxyproline at the Xaa Position in Collagen by Mass Spectrometry” has just been accepted for publication in the Journal of Proteome Research, an ACS scientific journal.

In this work, an atmospheric aerosol assisted pulsed plasma process is reported as an environmentally friendly technique for the preparation of tunable catechol-bearing thin films under solvent and catalyst free conditions.

The S2MOs laboratory is involved in the ALPO Interreg project that aims at producing building blocks for polymer preparation starting from the micro-algae biomass....

Tuleariocaris holthuisi and Arete indicus are two ectocommensal shrimps closely associated with the tropical sea urchin Echinometra mathaei. This study provides a comparison of these two E. mathaei symbiotic crustaceans and particularly focuses on the relationship between T....

In the present paper, we submitted protonated tailor-made peptoids to (energy-resolved) collision-induced dissociation experiments to investigate the side-chain loss reaction mechanisms....

In this manuscript, a novel solvent-free and organocatalyzed ring-opening (co)polymerization (ORO(c)P) method utilizing benzoic acid(BA) as simple thermostable carboxylic acid-type catalyst is proposed to not only produce structurally well-defined aliphatic homopolyesters derived from L-lactide (L-LA) and Ɛ-caprolactone (CL), but also and, unexpectedly, statistical copolyesters based on the two monomer units. RO(c)P reactions were conducted in bulk in a  temperature range of 155-180°C, in presence of alcohols as initiators.

In this manuscript, the new conjugated poly(4,4-bis(2- ethylhexyl)cyclopentadithiophene-alt-p-phenylene) (PCPDTPP) has been synthesized in a controlled way via catalyst transfer condensative polymerization (CTCP) of the corresponding bi-aryl monomer....

On Friday October 11, Corentin Decroo, M.Sc., successfully presented his doctorate results to a jury composed of Professors Isabelle Fournier (Lille), Catherine Lavaud (Reims), Pierre Duez, Jérôme Cornil, Roberto Lazzaroni, Patrick Flammang and Pascal Gerbaux.

This work presents the controlled synthesis and characterization of star shaped poly(3-alkylthiophene) (P3AT). The perfect control over the synthesis was mostly confirmed by MALDI mass spectrometry.  The originality of this study was the synthesis of controlled star-shaped polymers (P3AT)  presenting the formation of a strong (chiral) supramolecular organization into fibers, different and stronger obtained with the linear P3ATs...

In this work, we probed the gas phase structure of alkylamines/Ag+ complexes by ion mobility mass spectrometry and tandem mass spectrometry with the support of DFT-level calculations....

Peptoids are an emergent class of biosynthetic foldamers finding applications in area such as chiral resolution or catalysis [10-11]. CD and NMR are the common techniques used to decipher the secondary structures of peptoid oligomers in solution [5-6]. IMMS represents an elegant way to access to the gas-phase structure of ions. ...

Brasseur et al., Mapping of Spinochromes in the Body of Three Tropical Shallow Water Sea Urchins, Natural Product Communications, just accepted.

Pascal Gerbaux and Luisa Mattoli (Aboca, Italy) have officiated as chair and co-chair of the Natural substances and their complexes” session at the International Conference of Mass Spectrometry, IMSC 2018. This conference was organized in Florence between August 26 and 31 and gathered 1800 attendees from 70 different countries.

We have developed the PEPDROID force field by evaluating a new set of parameters to be incorporated in the original DREIDING force field and applied to (α or β) peptoids bearing different type of side chains.

BBQ chimistes 2015-2016