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A new decontamination textile involving a cyclodextrin derivative bearing an iodosobenzoate group was developed. It proved its efficiency against soman to decontaminate solid surfaces and to allow up to 3- to 4-fold improvement in accelerating the hydrolysis of the toxic compound under mild conditions. This opens the way to new technologies for decontamination of tools and designing of self-decontaminating protective equipment against chemical weapons. [ABSTRACT FROM AUTHOR]

Novel 2,3-heterodisubstituted β-cyclodextrin derivatives were designed as artificial enzymes to degrade chemical warfare agents. One of them reduced the acetylcholinesterase inhibitory potential by soman faster than its monosubstituted analog. [ABSTRACT FROM AUTHOR]

A novel cobalt corrole bearing 4-vinylphenyl groups at the 5,10,15- meso -positions of the macrocycle has been synthesized from tris(4-bromophenyl)corrole using a Suzuki coupling reaction. The spectral and electrochemical properties are reported in CH 2 Cl 2 along with its ability to form a highly stable six-coordinate complex and cross-linked corrole-based polymer in a 59% yield.

The Double degree in Health and Sciences (DCSS) provides an early training in research for future healthcare professionals. The profound transformation of the healthcare system and the advent of new analytical and digital technologies highlight the urgent need to link research to clinical practice. At the international level, especially in the United States, these programs point out the key role of healthcare professionals with both medical and scientific expertise. In France, a DCSS during medical studies was set up in the 2000's. This training is still heterogeneous and is not organized in all Faculties of Health Sciences. The Rouen Faculty of Health Sciences observed in 2016 that the number of students involved in DCSS was very low or even zero, depending on the year. The Rouen Faculty of Health Sciences initiated an institutional support in 2017 that led to the creation of a student mentorship dedicated to DCSS. This mentorship and the institutional leaders of this course have initiated a theoretical and practical training program. The organization of the DCSS of the Rouen Faculty of Health Sciences and the creation of a student mentorship program enabled us to increase the number of candidates interested in the DCSS (from 2 in 2016 to 26 in 2021) and to obtain an institutional recognition of this double major., (© 2022 médecine/sciences – Inserm.)

Magnetic resonance imaging (MRI) is a powerful tool for non-invasive, high-resolution three-dimensional medical imaging of anatomical structures such as organs and tissues. The use of contrast agents based on gadolinium chelates started in 1988 to improve the quality of the image, since researchers and industry focused their attention on the development of more efficient and stable structures. This review is about the state of the art of MRI contrast agents based on cyclodextrin scaffolds. Chemical engineering strategies are herein reported including host-guest inclusion complexation and covalent linkages. It also offers descriptions of the MRI properties and in vitro and in vivo biomedical applications of these emerging macrostructures. It highlights that these supramolecular associations can improve the image contrast, the sensitivity, and the efficiency of MRI diagnosis by targeting cancer tumors and other diseases with success proving the great potential of this natural macrocycle., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

A molecularly imprinted polymer containing a porphyrin unit was developed as a biomimetic heterogenous catalyst for the oxidation of sulfur derivatives. Its catalytic efficiency under mild conditions and its easy recovery represent a great asset for the design of new decontamination tools for yperite and VX.

The grafting of 5-iodoisatin heterocycle on a cyclic olefin copolymer (COC) and a gold surface was performed using a heterogeneous phase Sonogashira reaction consisting of coupling 5-iodoisatin with an arylalkyne previously introduced onto the surfaces. This optimized strategy takes advantage of the well-established methodology to functionalize COC or gold surfaces using aryldiazonium surface chemistry. Herein, we reported the first example of an isatin decorated polymeric or metallic surface. The surfaces were analyzed with a combination of techniques such as IR (Infrared spectroscopy), XPS (X-Ray photoelectron spectroscopy) and SPR (surface plasmon resonance). Docking studies showed that isatin and two derivatives interact with AmiC, a dimeric protein produced by Pseudomonas aeruginosa. Bacterial adhesion on isatin-COC platform was also observed. This general strategy for robust surface functionalization represents an easy approach for patterning surfaces with compounds of biological interest, allowing access to a large panel of original biosensors., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Liposomes loaded with drug–cyclodextrin complexes are widely used as drug delivery systems, especially for species with low aqueous solubility and stability. Investigation of the intimate interactions of macrocycles with liposomes are essential for formulation of efficient and stable drug-in-cyclodextrin-in-liposome carriers. In this work, we reported the preparation of unilamellar vesicles of 1-palmitoyl-2-oleoyl- sn -glycero-3-phosphocholine (POPC) embedded with native β-cyclodextrin and two synthetic derivatives: heptakis(2,3,6-tri- O -methyl)-β-cyclodextrin (TMCD) and heptakis(2,3-di- O -acetyl)-β-cyclodextrin (DACD). We then studied the effect of these macrocycles on the liposomal size, membrane viscosity, and liposomal stability at different temperatures and concentrations. We observed that TMCD and DACD affected vesicle size and the change of size was related to CD concentration. Irrespective of its nature, the macrocycle established interactions with the phospholipidic head groups, preventing cyclodextrins to diffuse into the lipid bilayer, as confirmed by molecular dynamics simulations. Such supramolecular structuring improves liposome stability making these colloid systems promising carriers for biologically active compounds.

New derivatives of cyclodextrins were prepared in order to determine the relative importance of the structural key elements involved in the degradation of organophosphorus nerve agents. To avoid a competitive inclusion between the organophosphorus substrate and the iodosobenzoate group, responsible for its degradation, the latter group had to be covalently bound to the cyclodextrin scaffold. Although the presence of the α nucleophile iodosobenzoate was a determinant in the hydrolysis process, an imidazole group was added to get a synergistic effect towards the degradation of the agents. The degradation efficiency was found to be dependent on the relative position of the heterocycle towards the reactive group as well as on the nature of the organophosphorus derivative.

The aim of this review is to provide an update on the current use of cyclodextrins against organophosphorus compound intoxications. Organophosphorus pesticides and nerve agents play a determinant role in the inhibition of cholinesterases. The cyclic structure of cyclodextrins and their toroidal shape are perfectly suitable to design new chemical scavengers able to trap and hydrolyze the organophosphorus compounds before they reach their biological target.

As standard therapy of intoxication with organophosphorus (OP) compounds is still insufficient, developing new treatment strategies is urgently required. For evaluating potential of OP detoxification of several compounds correctly, different toxicodynamic impact of OP enantiomers has to be considered thoroughly. It has already been demonstrated that β-cyclodextrin (β-CD) derivatives with attached nucleophilic substituent iodosobenzoic acid (IBA) can be regarded as potent OP scavengers due to an accelerating effect on decay of different OP. Herein, six CD derivatives permethylated or not on CD torus as well as differently attached nucleophilic substituent IBA derivative were investigated regarding detoxification of GF as an OP model substance. Acceleration of GF detoxification could be detected for all compounds with highest rate constants for propylene chain linked nucleophilic substituents on CD derivative. In addition, fast initial binding of GF on CD could be observed and is ascribed to formation of CD complexes. Furthermore, terminal plateau phase was detected of about 1% of each enantiomer reflecting the necessity of a quantitative determination at low concentrations. Moreover, this molecular depot formation may represent an additional detoxification pathway for OP., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Current treatments of organophosphorus nerve agents poisoning are imperfect, and more efficient medical countermeasures need to be developed. Chemical scavengers based on β-cyclodextrin displayed promising results, but further investigations have to be performed to evaluate the possibility of application of substituted cyclodextrins as potential detoxification agents. Herein, five new cyclodextrins scavengers were synthesized. New optimal conditions for regioselectively monosubstitution of β-cyclodextrin at O-2 position were then studied to access to key intermediates. After these optimizations, a new series of three permethylated derivatives was developed, and two compounds bearing an α-nucleophilic group via a three carbon atoms linker were prepared. The ability of these five scavengers to detoxify nerve agents (cyclosarin, soman, tabun and VX) was evaluated by a semi-quantitative biological assay. All the modified cyclodextrins significantly decreased the inhibitory effect of chemical warfare G agents on acetylcholinesterase activity. For this purpose, we showed that the specific interactions between the organophosphorus compound and the oligosaccharidic moiety of the scavenger played a pivotal role in the detoxification process., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

A new generation of organophosphate (OP) scavengers was obtained by synthesis of β-cyclodextrin-oxime derivatives 8-12. Selective monosubstitution of β-cyclodextrin was the main difficulty in order to access these compounds, because reaction onto the oligosaccharide was closely related to the nature of the incoming group. For this purpose, non-conventional activation conditions were also evaluated. Intermediates 5 and 7 were then obtained with the better yields under ultrasounds irradiation. Finally, the desired compounds 8-10 were obtained from 5-7 in high purity by desilylation using potassium fluoride. Quaternarisation of compounds 8 and 9 was carried out. OP hydrolytic activity of compounds 8-12 was evaluated against cyclosarin (GF) and VX. None of the tested compounds was active against VX, but these five cyclodextrin derivatives detoxified GF, and the most active scavengers 10 and 11 allowed an almost complete hydrolysis of GF within 10 min. Even more fascinating is the fact that compounds 9 and 10 were able to hydrolyze enantioselectively GF.

Developing potent detoxification strategies for prophylaxis and therapy against organophosphate (OP) intoxication still represents a challenging task. Clinical application of numerous investigated substances including enzymes and low molecular scavengers like metal ions or nucleophiles could not yet be realised due to profound disadvantages. Presenting a promising attempt, cyclodextrins (CDs) efficiently enhance the degradation of some organophosphorus compounds. The present study examined the in vitro GF degradation mediated by three CDs and a nucleophilic precursor performed by mass spectrometric detection with ammonia chemical ionisation. All four compounds caused a notable enhancement of GF detoxification that was synergistically accelerated in the case of 2-O-(3-carboxy-4-iodosobenzyl)-β-cyclodextrin (IBA-β-CD) with the alpha-nucleophile 2-iodosobenzoic acid (IBA) grafted on the secondary face of β-cyclodextrin (β-CD). In vitro toxicokinetic investigations of CD derivatives are needed to evaluate the effect of slow terminal elimination phase of the more toxic (-)-GF shown for two CD-derivatives underlining the necessity of detecting the complete kinetic course of inactivation. The observed effect of fast high affinity binding (20-30%) represents an additional therapeutic option of an extremely rapid reduction of GF concentration in vivo. Distinctive differences in the course of reaction are detected depending on β-CD-derivatives, allowing a first inference of possible mechanisms and relevance of attached substituents. However, further profound investigation needs to be done to evaluate the basis of a clinical application of substituted CDs as potential detoxification agents., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

The goal of this study was to assess mitochondrial function and ROS production in an experimental model of cocaine-induced cardiac dysfunction. We hypothesized that cocaine abuse may lead to altered mitochondrial function that in turn may cause left ventricular dysfunction. Seven days of cocaine administration to rats led to an increased oxygen consumption detected in cardiac fibers, specifically through complex I and complex III. ROS levels were increased, specifically in interfibrillar mitochondria. In parallel there was a decrease in ATP synthesis, whereas no difference was observed in subsarcolemmal mitochondria. This uncoupling effect on oxidative phosphorylation was not detectable after short-term exposure to cocaine, suggesting that these mitochondrial abnormalities were a late rather than a primary event in the pathological response to cocaine. MitoQ, a mitochondrial-targeted antioxidant, was shown to completely prevent these mitochondrial abnormalities as well as cardiac dysfunction characterized here by a diastolic dysfunction studied with a conductance catheter to obtain pressure-volume data. Taken together, these results extend previous studies and demonstrate that cocaine-induced cardiac dysfunction may be due to a mitochondrial defect., (Copyright 2010 Elsevier Inc. All rights reserved.)

Formation of a copper(ii)-beta-cyclodextrin (beta-CD) complex in an aqueous medium allowed the regioselective introduction into the oligosaccharide of a benzyl or a bromo-allyl substituent at O-3.

The stability of N-substituted derivatives of thalidomide was studied and compared to that of thalidomide itself. Nitrogen atom included in glutarimide ring was successively substituted by a hydroxy group, a methyl acetate group, and an ethyl group. Lipophilicities of these compounds were determined using the method based on experimental determinations of partition coefficients developed by Hansch. Hydroxy group led to a decrease of lipophilicity. Substitution of the nitrogen atom by an ethyl group or a methyl acetate group allowed an increase of lipophilicity. Relative stabilities of each compound were determined under physiological conditions: pH (7.4) and temperature (37 degrees C) using high performance liquid chromatography procedure. The program Sigma Plot was used to fit experimental data in order to obtain the half-lifes of thalidomide and its analogs. In the case of substitution by an ethyl group, the increase of lipophilicity (Delta log P = 0.36) was in agreement with a higher stability in aqueous medium. In the case of methyl acetate group, hydrolysis of the cycle was chemically favoured despite a higher lipophilicity compared to those of thalidomide. In the case of N-hydroxy compound, the decrease in lipophilicity was not sufficient to affect the stability.

Among all molecules used to develop biomimetic catalysts, cyclodextrins are extremely attractive compounds. These oligosaccharides can form inclusion complexes with various organic substrates and in particular with organophosphorus poisons, which are widely used as chemical weapons and insecticides. Soman, a frightening neurotoxic agent, once "trapped" in the internal cavity of beta-cyclodextrin can moreover undergo the nucleophilic attack of an oligosaccharide hydroxyl group, miming the first step of the enzymatic process. Selective substitution of beta-cyclodextrin by a 2-iodosobenzoic acid derivative has enabled effective synthesis of scavangers against organophosphorus compounds. Hydrolysis trials were carried out with paraoxon, as an organophosphorus model. The OP-hydrolyzing activity could reach more than two order of magnitude compared with free 2-iodosobenzoïc acid. Nevertheless, hydrolysis of paraoxon showed saturation kinetics. Although the activity was strongly dependent on the relative position of the reactive group, these results showed the interest of a strategy, resulting in the "trapping" of the organophosphorus substrate in the internal cavity of the oligosaccharide in order to maintain it near the catalytic function.

A comparative study of reaction conditions was performed for the synthesis of a 2-O-monobenzyl ether of cyclomaltoheptaose (beta-CD). Optimal conditions involved sodium ethoxide in Me(2)SO and benzyl bromide. The methodology was extended to the preparation of various 2(I)-O-iodobenzyl and 2(I)-O-carboxymethylbenzyl derivatives of beta-CD including a 3-carboxymethyl-4-iodobenzyl derivative of interest as precursor of an enzyme mimic to degrade the organophosphoryl ester diethyl 4-nitrophenyl phosphate (paraoxon).

Beta-cyclodextrin was substituted by an iodosobenzoic acid derivative to create a catalytic hydrolytic activity against neurotoxic organophosphorus agents. The catalytic moiety was introduced on a secondary hydroxy group at the position 2 of a glucose unit. Several beta-cyclodextrin derivatives were obtained. In these derivatives, the methylene linker occupied all potential positions on the aromatic ring. Kinetic assays were carried out with paraoxon as organophosphate model. Three regioisomers hydrolyzed paraoxon, although the paraoxon-leaving group, para-nitrophenol, was not released from the beta-cyclodextrin torus.

Both enantiomers of methyloctalone were oxidized by a biomimetic manganese/porphyrin/imidazole catalytic system in order to obtain sufficient amounts of various model metabolites. The double bond proved to be less sensitive than the ring methylenes. Hydroxylation occurred mainly in the allylic position (position 8) and also at positions 7 and 6. In position 8, two diastereomers were obtained while in positions 7 and 6 the reaction was diastereospecific. In the case of position 8 only the oxidation yielded a keto compound. The efficiency of this method for the preparation of functionalized chiral synthons was better than it was for biological pathways., (Copyright 2004 Wiley-Liss, Inc.)

In order to examine the biotransformations of xenobiotics, it is essential to realize studies of metabolism of drugs in living animals. It is generally difficult to extract quantitatively the metabolites from biological media or excreta. Alternative methods have then been developed. Application of such techniques to 4a-methylhexahydronaphthalenones, which constitute starting material for the stereospecific synthesis of terpenoids or steroids, is particularly demonstrative. By biosynthetical ways, it was not possible to access with good yields to all the metabolites obtained in vivo. A novel methodology, based on the use of a manganoporphyrin catalyst, allowed to synthesize large amounts of several models of metabolites corresponding to those which had been isolated in living rats. Only one of the metabolites obtained in vivo could not be synthesized by this biomimetic system. This proved that alternative methods are precious to obtain models with good yields, but need to be validated by controls in living animals.

The conditions of the use of the manganese/porphyrin/imidazole system needed to be improved in order to obtain larger amounts of models of metabolites. An increase of the oxidation yields and a better preservation of this catalytic system have been obtained on the examples of various alkanes, by an acid addition in the reaction mixture. Three manganoporphyrins were checked for evaluation of the reaction. These results were extended to molecules of therapeutical interest such as ibuprofen and phenylbutazone.

Tetraalkylammonium (TAA) salts are well known reversible inhibitors of cholinesterases. However, at concentrations around 10 mm, they have been found to activate the hydrolysis of positively charged substrates, catalyzed by wild-type human butyrylcholinesterase (EC 3.1.1.8) [Erdoes, E.G., Foldes, F.F., Zsigmond, E.K., Baart, N. & Zwartz, J.A. (1958) Science 128, 92]. The present study was undertaken to determine whether the peripheral anionic site (PAS) of human BuChE (Y332, D70) and/or the catalytic substrate binding site (CS) (W82, A328) are involved in this phenomenon. For this purpose, the kinetics of butyrylthiocholine (BTC) hydrolysis by wild-type human BuChE, by selected mutants and by horse BuChE was carried out at 25 degreeC and pH 7.0 in the presence of tetraethylammonium (TEA). It appears that human enzymes with more intact structure of the PAS show more prominent activation phenomenon. The following explanation has been put forward: TEA competes with the substrate at the peripheral site thus inhibiting the substrate hydrolysis at the CS. As the inhibition by TEA is less effective than the substrate inhibition itself, it mimics activation. At the concentrations around 40 mm, well within the range of TEA competition at both substrate binding sites, it lowers the activity of all tested enzymes.