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Despite strong indications of antimycobacterial activities for clitocybins reported since 1945, no reports linking chemical structure and activity have been reported in the literature since then. In this study, we synthesized some clitocybin derivatives (also called 2-substituted-isoindolinones), and tested their activities and carried out some chemical derivations. Isoindolinones were prepared from methyl 2-formyl-3,5-dimethoxybenzoate and various primary aromatic amines. Compounds were evaluated for in vitro activity against Mycobacterium tuberculosis H37Rv, as well as for cytotoxicity (CC50) on the Vero cell line. 4,6-dihydroxy-2-(4-hydroxyphenyl)isoindolin-1-one, 7, and 4-hydroxy-2-(4-hydroxyphenyl)-6-methoxy-isoindol-1-one, 5, exhibited the highest antimycobacterial activities (minimum inhibitory concentration = 19.45 µM and 18.45 µM, respectively) and were non-toxic (CC50 = 30 µM and 29 µM, respectively).

The recycling of Risidu Pet-Al (a laminated foil made from polyethylene and aluminum foil in food brike packaging) continues to be a challenge. Despite the fact that previous studies proposed green solutions for the recycling of the Pet-Al composite, the handicaps linked to the increase of the cost of the reagents involved in the recycling mechanism, the complexity of the steps, resulting in products with a critical aspect, really reflect a problem. The growing concern about environmental impacts such as greenhouse gas emissions from inceneration treatment is distinctly clear to the scientific community. This article involves chemical treatment by adding a strong base NaOH or KOH as the dissolving reagent, Followed by the addition of the strong acid HCl . The birth of a neutral environment promotes the recovery of aluminum salts as well as sodium (or potassium). The released H2, polyethylene and cardboard are also products regenerated by this recycling.The study contributes to the optimal conditions of time concentration temperature as well as the mode of separation. The recovered salts are identified, however their purity remains an important factor of quality before adapting their use.

Hybrid nanocomposites were obtained in this study by solid–solid reaction based on calixarenic derivatives and natural Tunisian clay: clay-calixarene. For this purpose, two calixarenic derivatives were synthesized and their properties were studied. Results show their affinity towards bivalent mercury and lithium by complexation in a homogeneous medium and vis-a-vis the rubidium by extraction of water to dichloromethane. The clay was purified and characterized by means of X-ray diffraction, X-ray fluorescence, cation exchange capacity and BET techniques. Intercalation of the calixarenes in the interfoliar space of the clay has been demonstrated by the spacing of the basal space after reaction and the comparison of infrared spectra confirms that the reaction has taken place. In addition, these hybrids have developed important specific surfaces area. Both nanocomposites prepared are among the first synthesis of clay-calixarenic hybrids in solid state. According to the calixarenic structures, it is assumed that these materials were of class II hybrids.

The four new multivalent ligands 5-8 derived from calix[4]arene and thiacalix[4]arene backbones in 1,3-Alternate conformation bearing ortho-imino- and ortho-amino-methylpyridine chelating sites have been designed, prepared and characterized. Owing to the imposed 1,3-Alternate conformation of the backbone, ligands 5-8 offer two coordinating pockets composed of two sets of chelates located above and below the mean place of the macrocyclic framework. Ligands 6-8, independent of the nature of the anion associated with Ag+ cation, form binuclear silver complexes (AgX, X = BF4-, PF6-, SbF6-, AsF6-, NO3-) in solution and in the solid state. Ligand 7, in the presence of an excess of Ag+, also forms tetranuclear silver complexes 7-(AgBF4)4, and 7-(AgNO3)4 in presence of two different auxiliary ligands (H2O or NO3-) that have been characterized in the solid state. Due to a rather short Ag-Ag distance of ca 2.89 A, the tetranuclear complex 7-(AgBF4)4 is emissive in the solid state, at 298 K (λexc = 295 nm, λem = 425 nm) resulting from argentophilic interactions between the closely positioned silver cations.

International audience; Opportunistic Gram-negative Pseudomonas aeruginosa uses adhesins (e.g., LecA and LecB lectins, type VI pili and flagella) and iron to invade host cells with the formation of a biofilm, a thick barrier that protects bacteria from drugs and host immune system. Hindering iron uptake and disrupting adhesins’ function could be a relevant antipseudomonal strategy. To test this hypothesis, we designed an iron-chelating glycocluster incorporating a tetrahydroxamic acid and α-l-fucose bearing linker to interfere with both iron uptake and the glycan recognition process involving the LecB lectin. Iron depletion led to increased production of the siderophore pyoverdine by P. aeruginosa to counteract the loss of iron uptake, and strong biofilm inhibition was observed not only with the α-l-fucocluster (72%), but also with its α-d-manno (84%), and α-d-gluco (92%) counterparts used as negative controls. This unprecedented finding suggests that both LecB and biofilm inhibition are closely related to the presence of hydroxamic acid groups.

International audience; Glycan-protein interactions control numerous biological events from cell-cell recognition and signaling to pathogen host cell attachment for infections. To infect cells, some viruses bind to immune cells with the help of DC-SIGN (dendritic cell [DC]-specific ICAM3-grabbing nonintegrin) C-type lectin expressed on dendritic and macrophage cell membranes, via their envelope protein. Prevention of this infectious interaction is a serious therapeutic option. Here, we describe the synthesis of the first water-soluble tetravalent fucocluster pseudopeptide-based 1,3-alternate thiacalixarenes as viral antigen mimics designed for the inhibition of DC-SIGN, to prevent viral particle uptake. Their preparation exploits straightforward convergent strategies involving one-pot Ugi four-component (Ugi-4CR) and azido-alkyne click chemistry reactions as key steps. Surface plasmon resonance showed strong inhibition of DC-SIGN interaction properties by tetravalent ligands designed with high relative potencies and β avidity factors. All ligands block DC-SIGN active sites at nanomolar IC50 preventing cis-cell infection by Ebola viral particles pseudotyped with EBOV glycoprotein (Zaire species of Ebola virus) on Jurkat cells that express DC-SIGN. In addition, we observed strong inhibition of DC-SIGN/human cytomegalovirus (HCMV)-gB recombinant glycoprotein interaction. This finding opens the way to the simple development of new models of water-soluble glycocluster-based thia-calixarenes with wide-ranging antimicrobial activities.

We optimized Origanum majorana (OM) extraction for mild steel corrosion inhibition in neutral 0.5 M chloride medium. The inhibition mechanism evolved in presence of the optimal extract was discussed when calculating the activation energy (Ea), the activation enthalpy (ΔaH) as well as the activation entropy (ΔaS). The OM extract molecules were investigated using the density functional theory (DFT) at B3LYP/6-31G(d,p) basis set level. 1-methyl-4-propan-2-ylcyclohexa-1,3-diene alpha-terpinene was predicted exhibiting the most inhibition capabilities.

The synthesis and catalytic activity of a series of tris-half sandwich cyclopentadienyl nickel (II) N-heterocyclic carbene (NHC) complexes, that have approximate C3 symmetry, is described. The molecules consist of [Ni(NHC)BrCp] groups (Cp = η-C5H5) in which the NHC ligand is grafted on to the lower rim of a 1,3,5 trimethoxy p-tert butylcalix [6] arene via methylene spacers. These species are all synthesized from 1,3,5-trimethoxy-2,4,6 tris-substituted imidazolium tribromide salts via reactions with nickelocene. All complexes were fully characterized by 1H and 13C NMR spectroscopy and by mass spectrometry. Their catalytic activity in the Suzuki-Miyaura cross coupling reaction was probed.

International audience; A series of novel 6-amino-2-aryl-3H-indolone-N-oxides were synthesized at yields of up to 65% and characterized; onewas further characterized using X-ray crystallographic analysis.Synthesized compounds were evaluated for their in vitro activity against a chloroquine-resistant (FcB1) strain of Plasmodium falciparum, as well as for the 50% cytotoxic concentration (CC50) on Vero cell lines. The most promising activities were observed for the fluorinated compounds, the most active in vitro being 6-(2-morpholinoacetamido)-2-(4-(trifluoromethoxy)phenyl)-3H-indolone-N-oxide (IC50: 15.5 nM). In addition, these compounds showed weak cytotoxicity leading to selectivity index values of >170, thus warranting further in vitro and in vivo studies.

Described herein is a convenient, odorless, metal-free, one-pot strategy for the synthesis of unsymmetrical thioethers. The key step in this new strategy is a base-catalyzed 1,5-thiol transfer reaction via a pseudointramolecular mechanism of a 1-bromo-2-alkylthiolcarbonate, which is itself obtained through a straightforward microwave-assisted thioalkylation of a 1,2-cyclic-thionocarbonate precursor with an appropriate alkyl bromide. The starting 1,2-cyclic-thionocarbonates are easily obtained from the corresponding diols. When a propargylthiolcarbonate constitutes the key alkylthiolcarbonate 1,5-shift precursor, a copper-mediated dipolar cycloaddition reaction ("click") with azide partners is rendered possible. This increases the versatility of the approach, as a very large variety of complex triazole-tethered substrates can potentially be integrated into the target unsymmetrical thioether final products. As an example of the scope of the reaction, four 1,5-shift reactions have been triggered simultaneously from a sugar-derived tetrathiolcarbonate precursor using base catalysis, to allow four 6-thioglucose moieties to be installed (78% yield for each sugar unit) onto a 1,3-alternate thiacalix[4]arene scaffold in a one-pot transformation.

International audience; Five new multivalent ligands based on either p-tert-butylthiacalix[4]arene (TCA) 1 or p-tertbutylcalix[4]arene (CA) 2 backbones in 1,3-Alternate conformation bearing four oxamate coordinating groups at their lower rim were designed and synthesized by a multistep strategy. These ligands differ either by the nature of the calix[4]arene backbone (CA or TCA) or by the nature of the spacer ((CH2)n) connecting the oxamate binding units to the backbone.

Dedicated to Professor Vincenzo Balzani on the occasion of his 80th birthday; International audience; Pillar[5]arene derivatives bearing peripheral porphyrin subunits have been efficiently prepared from a decaazide pillar[5]arene building block (17) and ZnII-porphyrin derivatives bearing a terminal alkyne function (9 and 16). For the resulting deca-ZnII-porphyrin arrays (18 and 20), variable temperature NMR studies revealed an intramolecular complexation of the peripheral ZnII-porphyrin moieties by 1,2,3-triazole subunits. As a result, the molecules adopt a folded conformation. This was further confirmed by UV/Visspectroscopy and cyclic voltammetry. In addition, we have also demonstrated that the coordination-driven unfolding of 18 and 20 can be controlled by an external chemical stimulus.Specifically, addition of an imidazole derivative (22) to solution of 18 or 20 breaks the intramolecular coordination at the origin of the folding. The resulting molecular motions triggered by the addition of the imidazole ligand mimic the blooming of a flower.

Herein, the multistep synthesis of eight new ligands based on either calix[4]arene or thiacalix[4]arene backbone blocked in a 1,3-alternate conformation was achieved. Both types of backbones were functionalized with pyridyl coordinating units using either imino or amino junctions. The introduction of the pyridyl units was achieved using either the position 3 (meta) or 4 (para) of the aromatic moiety. Moreover, four out of the eight ligands were structurally investigated in the solid state via X-ray diffraction methods on single crystals.

International audience; Combinations of six new coordinating tectons (3-8) tetrakis-pyrazolyl appended calix[4]arenes, blocked in 1,3-A conformation, based on 1 (tetrathiacalix[4]arene) and 2 (tetrathiatetramercaptocalix[4]arene) derivatives, with AgX salts (X = NO3-, BF4-, XF6-(X = P, As and Sb)) lead to nine new silver coordination networks. The flexible nature of tectons 3-8 (length of the spacer between the macrocycle and the pyrazolyl coordinating unit), their high number of potential coordinating sites and the loose coordination demand of Ag + cation lead to the formation of a large variety of networks with different dimensionality: from 1D (5-AgSbF6, 5-AgBF4, 7-AgSbF6 and 8-AgNO3) to extended 2D (6-AgBF4 and 8-AgSbF6) and to a series of three isostructural porous diamond-like 3D architectures (6-AgXF6 (X = P, As and Sb)).

Introduction . L’orange (Citrus aurantium sinensis ) est une source de composes bioactifs : vitamines C et E, flavonoides (flavanes et flavanones glycosyles et polymethoxyles). Pour valoriser les dechets des peaux d’orange, nous avons mesure l’activite antiradicalaire du jus et des peaux seches et fraiches de cinq varietes d’orangers de Tunisie afin d’evaluer leur concentration en composes antioxydants utilisables dans l’industrie. Materiel et methodes . Le pouvoir antiradicalaire du jus et des extraits des peaux a ete evalue en suivant, en fonction du temps, la disparition du radical stable DPPH• par spectrophotometrie d’absorption UV-visible a 515 nm. L’activite antiradicalaire mesuree a ete exprimee en concentration efficace (CE50). La determination du volume V50 de vitamine C d’une solution d’acide ascorbique de concentration connue et d’un volume V50 des extraits de jus et des peaux seches et fraiches d’orange a permis d’estimer la concentration molaire et massique de vitamine C equivalente dans les extraits. Resultats . Les jus d’orange contiennent environ 400 mg·L–1 d’equivalent de vitamine C. Dans le cas de reactions tres rapides avec le radical DPPH•, la totalite de l’activite antiradicalaire peut etre attribuee a la vitamine C. Dans le cas de reactions plus lentes, en plus de la vitamine C, ce sont les polyphenols (citroflavonoides) qui contribuent a l’activite antioxydante totale. Les extraits methanoliques des peaux fraiches (flavedo) contiennent plus de vitamine C que les extraits de peaux seches. Conclusion . Les peaux d’oranges constituent d’immenses sources d’antioxydants qui peuvent trouver leur application dans differents domaines : agroalimentaire, cosmetique, pharmaceutique et autres.

Экспериментальные и квантово-химические исследования были проведены для установления взаимосвязи между молекулами экстракта Malva sylvestris и их антикоррозийными свойствами. Экстракт растения представлял собой смесь химических реагентов, из которых только 4 были избыточными. Две группы молекул были определены путем использования квантово-химических параметров. С помощью электрохимических исследований растительный экстракт был классифицирован как ингибитор смешанного типа. Процент ингибирования составил всего лишь 54,5 %, вследствие антагонистического эффекта молекул экстракта., Experimental and quantum chemical investigations have been coupled in order to determine anticorrosion potential of Malva sylvestris extract molecules. The plant extract is a mixture of chemicals of which only four are abundant. Two groups of molecules are evidenced using quantum chemical parameters. The electrochemical investigation has classified the plant extract as a mixedtype inhibitor. The %EI has been only 54.5% due to antagonistic effects of the extract molecules.

The title compound, C(47)H(60)O(6).3CHCl(3), is the first example of a lower-rim mono-ester calixarene derivative to be crystallographically characterized. The cone conformation adopted by the macrocycle is stabilized by three intramolecular hydrogen bonds. Self-inclusion of the methyl ester chain in the cavity of an adjacent molecule gives rise to infinite chains parallel to the c axis. C-H...pi interactions involving the methyl group most imbedded in the cavity contribute to the stabilization of the system.

In the present work, the focus is the study of complexing and extracting properties of three nanoscale derivatives namely multicalixarenes 2C, 3C and 4C which the latter structure is a dendrimer structure of first generation. The metal cations included in this study are the alkali metal, alkaline earth metal, some transition metals, heavy metals and lanthanides. This study was conducted essentially in methanol to determine the stoichiometry of the complexes formed, or the location of the coordination sites, and finally to evaluate selectivity's. These studies have been conducted by UV-visible spectrophotometry, conductivity and proton NMR. The liquid-liquid extraction picrates metal cations followed by UV-visible showed strong selectivity dicalixarenic derived for sodium. The solid liquid extraction of metal picrates followed by 1H-NMR shows an intra- or intermolecular exchange of cations within the calixarene units studied nanocomposites.

The binding properties of three p-tert-butyldihomooxacalix[4]arene tetraketone derivatives (tert-butyl 2b, adamantyl 2c and phenyl 2d) in the cone conformation and one derivative (methyl 2a) in a partial cone conformation, towards alkali and alkaline earth metal cations have been established by extraction studies of metal picrates from water into dichloromethane, stability constant measurements in methanol and acetonitrile, and by H-1 NMR spectrometry. Transport experiments of metal picrates through a dichloromethane membrane were also performed. The results are compared to those obtained with closely-related calix[n]arene derivatives (n = 4 and 5) and discussed in terms of the substituents, size and conformational effects. Methylketone 2a is a poor binder for all the cations studied, due to its partial cone conformation. Ketones 2b, 2c and 2d show high extraction and complexation levels for the alkali cations, with similar profiles and preference for K+ and Na+ (plateau selectivity). Towards alkaline earth cations, these ketones show a strong peak selectivity for Ba2+ in extraction, but a plateau selectivity for Ca2+, Sr2+ and Ba2+ in complexation. The nature of the substituent attached to the ketone function has some influence on their binding properties, with phenylketone 2d being a slightly weaker binder than ketones 2b and 2c. H-1 NMR titrations confirm the formation of 1:1 complexes between the ketones and the cations studied, also indicating that they should be located inside the cavity defined by the phenoxy and carbonyl oxygen atoms. Ketones 2b, 2c and 2d show transport rates that do not follow, in general, the same trends observed in extraction and complexation.

Clickable pillar[5]arene building blocks have been used for the efficient grafting of peripheral subunits onto the macrocyclic core. New liquid-crystalline pillar[5]arene derivatives have been prepared by grafting either p-dodecyloxybenzoate groups or percec-type dendrons on the macrocyclic scaffold. On the other hand, pillar[5]arene derivatives bearing peripheral porphyrin subunits have been efficiently prepared from the clickable pillar[5]arene building block and Zn(II)-porphyrin derivatives bearing a terminal alkyne function. Owing to an intramolecular complexation of the peripheral Zn(II)-porphyrin moieties by 1,2,3-triazole subunits, an original dynamic conformational equilibrium leading to a folding of the molecules has been evidenced by variable temperature 1H NMR studies. Finally, a clickable [2]rotaxane scaffold incorporating a free-base porphyrin stopper has been prepared and functionalized with ten peripheral Zn(II)-porphyrin moieties to afford a sophisticated photoactive supramolecular device., La préparation de briques élémentaires de pillar[5]arènes « clickables » nous ont permis de construire des édifices moléculaires complexes, en greffant différents groupements fonctionnels autour du coeur macrocyclique. Dans ce contexte, des nouveaux dérivés du pillar[5]arène présentant des propriétés cristaux-liquides ont été synthétisés en greffant du p-dodecyloxybenzoate ou encore des dendrons de type percec. D’autres part, des dérivés pillarèniques portant des unités de porphyrines ont été préparés à partir du squelette « clickable » pillar[5]arène et de porphyrines de Zinc portant des fonctions alcynes vrai. Les études de ce système par RMN du proton à des températures variables ont permis de mettre en évidence un équilibre conformationnel dynamique conduisant au repliement des molécules. Ceci a été expliqué par une complexation intramoléculaire des porphyrines de Zinc par les groupements 1,2,3-triazole. Finalement un support « clickable » detype [2]rotaxane comportant une porphyrine base libre comme bouchon, a été préparé et ensuite fonctionnalisé par dix porphyrines de Zinc permettant l’obtention d’un dispositif supramoléculaire photoactif.

Molecular receptors are preorganised architectures held by covalent bonds and capable of binding selectively ionic and / or molecular substrates via various intermolecular interactions, leading to the formation of molecular complexes composed of at least two species.In this work, the synthesis of a library of calix[4]arene and its analogue thiacalix[4]arene in 1,3-alternate conformation based ligands and tectons has been investigated. These two types of platforms have been equipped with pyridine, catechol, imidazole, pyrazole and, for the first time, oxamate units as coordinating sites. All compounds prepared were characterized in solution and in some cases in the crystalline state. Their binding propensity in solution towards transition metals has been determined and discussed. For some derivatives, their metal extracting properties have been investigated and presented. Finally, the formation of extended periodic architectures of the coordination network type in the crystalline state by self-assembly of calixarene based tectons and silver cation was achieved and presented., Les récepteurs moléculaires sont des architectures maintenues par des liaisons covalentes et capables de fixer sélectivement des substances (ioniques et/ou moléculaires) au moyen d’interactions intermoléculaires diverses, aboutissant ainsi à la formation d’un assemblage d’au moins de deux espèces nommé complexe moléculaire. Au cours de ce travail, des stratégies de synthèse de dérivés de calix[4]arène et de son analogue thiacalix[4]arène en conformation 1,3-alternée ont été mises au point. Ces composés ont été fonctionnalisés par des groupements pyridine, catéchol, imidazole, pyrazole et pour la première fois oxamate. Les composés obtenus ont été caractérisés à la fois en solution par RMN et à l’état cristallin. Les propriétés complexantes vis-à-vis des métaux de transition en solution sont présentées. Pour certains dérivés, le pouvoir extractant envers les métaux de transition a été étudié et discuté. Enfin, la formation de réseaux de coordination à l’état cristallin par auto-assemblage de dérivés de calixarène ou de thiacalixarène et le cation argent est présentée et commentée.