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Piétrick Hudhomme - One of the best experts on this subject based on the ideXlab platform.
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This article is part of the Thematic Series "Tetrathiafulvalene chemistry".
2015Co-Authors: Yoann Cotelle, Marie Hardouin-lerouge, Stéphanie Legoupy, Piétrick Hudhomme, Olivier Alévêque, Eric LevillainAbstract:Glycoluril–tetrathiafulvalene molecular clips: on the influence of electronic and spatial properties for binding neutral accepting guest
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synthesis of Glycoluril tetrathiafulvalene molecular clips for electron deficient neutral guests through a straightforward diels alder strategy
New Journal of Chemistry, 2014Co-Authors: Marie Hardouinlerouge, Yoann Cotelle, Stéphanie Legoupy, Piétrick HudhommeAbstract:An electroactive molecular clip incorporating tetrathiafulvalene (TTF) sidewalls grafted on a Glycoluril platform has been synthesized using a straightforward Diels–Alder strategy. This way of attachment to the Glycoluril U-shape scaffold afforded a rigidified and closed receptor for which the electron-rich TTF pincers are expected to be at a suitable distance for sandwiching neutral guests through donor–acceptor interactions. The efficient complexation ability of this host architecture toward one molecule of tetracyanoquinodimethane derivative (F4-TCNQ) in solution has been demonstrated using cyclic voltammetry and UV-Visible titration methods.
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Synthesis of Glycoluril-tetrathiafulvalene molecular clips for electron-deficient neutral guests through a straightforward Diels–Alder strategy
New J. Chem., 2014Co-Authors: Marie Hardouin-lerouge, Yoann Cotelle, Stéphanie Legoupy, Piétrick HudhommeAbstract:An electroactive molecular clip incorporating tetrathiafulvalene (TTF) sidewalls grafted on a Glycoluril platform has been synthesized using a straightforward Diels–Alder strategy. This way of attachment to the Glycoluril U-shape scaffold afforded a rigidified and closed receptor for which the electron-rich TTF pincers are expected to be at a suitable distance for sandwiching neutral guests through donor–acceptor interactions. The efficient complexation ability of this host architecture toward one molecule of tetracyanoquinodimethane derivative (F4-TCNQ) in solution has been demonstrated using cyclic voltammetry and UV-Visible titration methods.
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Fused Glycoluril-tetrathiafulvalene molecular clips as receptors for neutral electron acceptor guests.
Organic Letters, 2014Co-Authors: Yoann Cotelle, Stéphanie Legoupy, Magali Allain, Piétrick HudhommeAbstract:Glycoluril-based molecular clips incorporating tetrathiafulvalene (TTF) sidewalls have been synthesized, and the efficient binding ability in solution of this host architecture toward m-dinitrobenzene through donor–acceptor interaction has been demonstrated.
Lyle Isaacs - One of the best experts on this subject based on the ideXlab platform.
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conformationally mobile acyclic cucurbit n uril type receptors derived from an s shaped methylene bridged Glycoluril pentamer
Supramolecular Chemistry, 2020Co-Authors: Kimberly G Brady, Vladimir Sindelař, Laura Gilberg, David Sigwalt, Joshua Bistanyriebman, Steven Murkli, Jared Klemm, Petr Kulhanek, Lyle IsaacsAbstract:We report the synthesis of the conformationally mobile S-shaped Glycoluril pentamer building block 3a and two new acyclic CB[n]-type receptors P1 and P2. P1 (9 mM) and P2 (11 mM) have moderate aque...
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Acyclic cucurbit[n]uril-type molecular containers: influence of Glycoluril oligomer length on their function as solubilizing agents
Organic & Biomolecular Chemistry, 2015Co-Authors: Laura Gilberg, Vladimir Sindelar, Peter Y. Zavalij, Ben Zhang, Lyle IsaacsAbstract:We present the synthesis of a series of six new Glycoluril derived molecular clips and acyclic CB[n]-type molecular containers (1–3) that all feature SO3− solubilizing groups but differ in the number of Glycoluril rings between the two terminal dialkoxyaromatic sidewalls. We report the X-ray crystal structure of 3b which shows that its dialkoxynaphthalene sidewalls actively define a hydrophobic cavity with high potential to engage in π–π interactions with insoluble aromatic guests. Compounds 1–3 possess very good solubility characteristics (≥38 mM) and undergo only very weak self-association (Ks < 92 M−1) in water. The weak self-association is attributed to unfavorable SO3−⋯SO3− electrostatic interactions in the putative dimers 12–42. Accordingly, we created phase solubility diagrams to study their ability to act as solubilizing agents for four water insoluble drugs (PBS-1086, camptothecin, β-estradiol, and ziprasidone). We find that the containers 3a and 3b which feature three Glycoluril rings between the terminal dialkoxy-o-xylylene and dialkoxynaphthalene sidewalls are less efficient solubilizing agents than 4a and 4b because of their smaller hydrophobic cavities. Containers 1 and 2 behave as molecular clip type receptors and therefore possess the ability to bind to and thereby solubilize aromatic drugs like camptothecin, ziprasidone, and PBS-1086.
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Synthesis and Self-Assembly Processes of Monofunctionalized Cucurbit[7]uril
2012Co-Authors: Brittany Vinciguerra, Liping Cao, Joe R. Cannon, Peter Y. Zavalij, Catherine Fenselau, Lyle IsaacsAbstract:We present a building-block approach toward functionalized CB[7] derivatives by the condensation of methylene-bridged Glycoluril hexamer 1 and Glycoluril bis(cyclic ethers) 2 and 12. The CB[7] derivatives Me2CB[7] and CyCB[7] are highly soluble in water (264 mM and 181 mM, respectively). As a result of the high intrinsic solubility of Me2CB[7], it is able to solubilize the insoluble benzimidazole drug albendazole. The reaction of hexamer 1 with Glycoluril derivative 12, which bears a primary alkyl chloride group, gives CB[7] derivative 18 in 16% isolated yield. Compound 18 reacts with NaN3 to yield azide-substituted CB[7] 19 in 81% yield, which subsequently undergoes click reaction with propargylammonium chloride (21) to yield CB[7] derivative 20 in 95% yield, which bears a covalently attached triazolyl ammonium group along its equator. The results of NMR spectroscopy (1H, variable-temperature, and DOSY) and electrospray mass spectrometry establish that 20 undergoes self-assembly to form a cyclic tetrameric assembly (204) in aqueous solution. CB[7] derivatives bearing reactive functional groups (e.g., N3, Cl) are now available for incorporation into more complex functional systems
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Metal-ion-induced folding and dimerization of a Glycoluril decamer in water.
Organic Letters, 2009Co-Authors: Wei-hao Huang, Peter Y. Zavalij, Lyle IsaacsAbstract:In a process reminiscent of RNA folding, acyclic Glycoluril decamer (±)-1 undergoes double helical assembly (red/green strands) in water triggered by the neutralization of regions of high electrostatic surface potential by metal cations (Li+, Na+, K+, Ca2+).
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Tetrameric molecular bowl assembled from Glycoluril building blocks
Chemical Communications, 2008Co-Authors: Nengfang She, Meng Gao, Xiang-gao Meng, Lyle IsaacsAbstract:Glycoluril derivative 1—whose bulky Ph–CC– substituents prevent formation of H-bonded tapes—undergoes solvent dependent assembly in the crystal; a tetrameric molecular bowl is formed by R44(24) H-bonding interactions from CH2Cl2 whereas DMF results in H-bond dimerization followed by oligomerization via C–H⋯π interactions.
Vladimir Sindelar - One of the best experts on this subject based on the ideXlab platform.
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Dimeric molecular clips based on Glycoluril
New Journal of Chemistry, 2017Co-Authors: Jan Sokolov, Tomáš Lízal, Vladimir SindelarAbstract:Glycoluril dimers 4a and 4b were prepared and successfully transformed to Glycoluril dimeric clips 7a and 7b. 1H NMR spectroscopy was used to reveal that the dimeric clip 7b with methyl substituents in its structure exists as a mixture of two distinct conformers in D2O at ambient temperature, while 7a possesses only one stable conformer under the same conditions due to its bulky phenyl substituents. The coalescence temperatures for 7b and its precursor 5b were determined. Both dimeric clips 7a and 7b formed complexes with methylviologen in D2O in which each of two clip-binding sites was occupied by one molecule of the guest. Thus, this study uncovers possible use of Glycoluril dimers 4a and 4b as general building blocks for Glycoluril-based supramolecular host molecules with two binding sites in their structure.
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Glycoluril Dimer Isomerization under Aqueous Acidic Conditions Related to Cucurbituril Formation
2016Co-Authors: Marek Štancl, Zuzana Garguláková, Vladimir SindelarAbstract:A water-soluble methylene-bridged Glycoluril dimer 2S was isolated. It was shown that 2S is the only kinetic product of the reaction between Glycoluril derivative 1 and paraformaldehyde. Compound 2S is subsequently intermolecularly transformed into its diastereomer 2C. The kinetics and thermodynamics of the S- to C-shaped dimer isomerization were investigated under reaction conditions similar to those for cucurbituril synthesis
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Propanediurea-Based Molecular Clips Bind Halide Anions: An Insight into the Mechanism of Cucurbituril Formation
2016Co-Authors: Tomáš Lízal, Marek Nečas, Lukas Ustrnul, Vladimir SindelarAbstract:The synthesis and supramolecular properties of the first methylene-bridged propanediurea-based dimers are described. These dimers, bearing an aromatic sidewall, have the shape of molecular clips. Unlike Glycoluril-based dimers, these clips neither dimerize nor accept any organic guests, due to their small cavities. Both propanediurea- and Glycoluril-based dimers bind halide anions on the convex side of the molecules, even in highly polar organic solvents. This observation brings new insights into the mechanism of cucurbituril formation
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Correction to “Glycoluril Dimer Isomerization under Aqueous Acidic Conditions Related to Cucurbituril Formation”
2016Co-Authors: Marek Štancl, Zuzana Garguláková, Vladimir SindelarAbstract:Correction to “Glycoluril Dimer Isomerization under Aqueous Acidic Conditions Related to Cucurbituril Formation
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Acyclic cucurbit[n]uril-type molecular containers: influence of Glycoluril oligomer length on their function as solubilizing agents
Organic & Biomolecular Chemistry, 2015Co-Authors: Laura Gilberg, Vladimir Sindelar, Peter Y. Zavalij, Ben Zhang, Lyle IsaacsAbstract:We present the synthesis of a series of six new Glycoluril derived molecular clips and acyclic CB[n]-type molecular containers (1–3) that all feature SO3− solubilizing groups but differ in the number of Glycoluril rings between the two terminal dialkoxyaromatic sidewalls. We report the X-ray crystal structure of 3b which shows that its dialkoxynaphthalene sidewalls actively define a hydrophobic cavity with high potential to engage in π–π interactions with insoluble aromatic guests. Compounds 1–3 possess very good solubility characteristics (≥38 mM) and undergo only very weak self-association (Ks < 92 M−1) in water. The weak self-association is attributed to unfavorable SO3−⋯SO3− electrostatic interactions in the putative dimers 12–42. Accordingly, we created phase solubility diagrams to study their ability to act as solubilizing agents for four water insoluble drugs (PBS-1086, camptothecin, β-estradiol, and ziprasidone). We find that the containers 3a and 3b which feature three Glycoluril rings between the terminal dialkoxy-o-xylylene and dialkoxynaphthalene sidewalls are less efficient solubilizing agents than 4a and 4b because of their smaller hydrophobic cavities. Containers 1 and 2 behave as molecular clip type receptors and therefore possess the ability to bind to and thereby solubilize aromatic drugs like camptothecin, ziprasidone, and PBS-1086.
Anthony I. Day - One of the best experts on this subject based on the ideXlab platform.
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Glycoluril derived cucurbituril analogues and the emergence of the most recent example: tiarauril.
Chemical Communications, 2020Co-Authors: Rajni Dhiman, Satyavisal Pen, Pradeep Kumar Chandrakumar, Terry J. Frankcombe, Anthony I. DayAbstract:Cucurbituril analogues can bear some of the chemical and physical characteristics of their parental origin and are derived wholly or in part from Glycolurils (including homologues). The development of analogues is discussed from their earliest origins to the most recent developments, which includes deviations in binding properties and the inclusion of alternative molecular units in conjunction with Glycolurils. Examples of alternative guest binding are discussed and compared to the behaviour of conventional cucurbituril.
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Bi(OTf)3 — A Mild Catalyst for the Synthesis of Difficult to Obtain C-Alkyl Substituted Glycolurils.
ChemInform, 2014Co-Authors: Vijaybabu Mandadapu, Anthony I. DayAbstract:Glycolurils [(III), (V), and (VIII)] are synthesized using Bi(OTf)3 instead of traditional acid catalysts.
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Fe(OTf)3 versus Bi(OTf)3 as mild catalysts in epoxide oxidative ring-opening, urea α-diketone condensation, and Glycoluril diether synthesis.
Organic Letters, 2014Co-Authors: Vijaybabu Mandadapu, Anthony I. DayAbstract:The salt Fe(OTf)3 has been shown to function as an effective catalyst in three different reactions, epoxide oxidative ring-opening to an α-hydroxy ketone, urea α-diketone condensation to form Glycolurils, and Glycoluril diether synthesis by formaldehyde condensation. In each of these reactions, Fe(OTf)3 was compared to Bi(OTf)3, a viable alternative catalyst with few or no prior examples of this type. Differences and advantages are highlighted but in most cases yields were generally high, and both catalysts outperformed conventional acid catalyzed methods.
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Fe(OTf)3 versus Bi(OTf)3 as Mild Catalysts in Epoxide Oxidative Ring-Opening, Urea α‑Diketone Condensation, and Glycoluril Diether Synthesis
2014Co-Authors: Vijaybabu Mandadapu, Anthony I. DayAbstract:The salt Fe(OTf)3 has been shown to function as an effective catalyst in three different reactions, epoxide oxidative ring-opening to an α-hydroxy ketone, urea α-diketone condensation to form Glycolurils, and Glycoluril diether synthesis by formaldehyde condensation. In each of these reactions, Fe(OTf)3 was compared to Bi(OTf)3, a viable alternative catalyst with few or no prior examples of this type. Differences and advantages are highlighted but in most cases yields were generally high, and both catalysts outperformed conventional acid catalyzed methods
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Bi(OTf)3—a mild catalyst for the synthesis of difficult to obtain C-alkyl substituted Glycolurils
Tetrahedron, 2013Co-Authors: Vijaybabu Mandadapu, Anthony I. DayAbstract:Abstract We have employed Bi(OTf)3 (5 mol %) a catalyst not previously used in the synthesis of urea condensation products from α-dicarbonyl compounds, as a mild method for the synthesis of difficult to obtain Glycolurils. There are limited synthetic examples of C-alkylated substituted Glycolurils and even fewer carrying functionality on the alkyl substituent. We have successfully synthesised some challenging examples of Glycolurils with functionality, which include norbornyl-based structures. The milder reaction conditions enables the isolation of defined intermediate diols and ureas in good yields, and Glycolurils are possible, where they would not normally be available under conventional acid catalyzed conditions.
Yoann Cotelle - One of the best experts on this subject based on the ideXlab platform.
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This article is part of the Thematic Series "Tetrathiafulvalene chemistry".
2015Co-Authors: Yoann Cotelle, Marie Hardouin-lerouge, Stéphanie Legoupy, Piétrick Hudhomme, Olivier Alévêque, Eric LevillainAbstract:Glycoluril–tetrathiafulvalene molecular clips: on the influence of electronic and spatial properties for binding neutral accepting guest
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synthesis of Glycoluril tetrathiafulvalene molecular clips for electron deficient neutral guests through a straightforward diels alder strategy
New Journal of Chemistry, 2014Co-Authors: Marie Hardouinlerouge, Yoann Cotelle, Stéphanie Legoupy, Piétrick HudhommeAbstract:An electroactive molecular clip incorporating tetrathiafulvalene (TTF) sidewalls grafted on a Glycoluril platform has been synthesized using a straightforward Diels–Alder strategy. This way of attachment to the Glycoluril U-shape scaffold afforded a rigidified and closed receptor for which the electron-rich TTF pincers are expected to be at a suitable distance for sandwiching neutral guests through donor–acceptor interactions. The efficient complexation ability of this host architecture toward one molecule of tetracyanoquinodimethane derivative (F4-TCNQ) in solution has been demonstrated using cyclic voltammetry and UV-Visible titration methods.
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Synthesis of Glycoluril-tetrathiafulvalene molecular clips for electron-deficient neutral guests through a straightforward Diels–Alder strategy
New J. Chem., 2014Co-Authors: Marie Hardouin-lerouge, Yoann Cotelle, Stéphanie Legoupy, Piétrick HudhommeAbstract:An electroactive molecular clip incorporating tetrathiafulvalene (TTF) sidewalls grafted on a Glycoluril platform has been synthesized using a straightforward Diels–Alder strategy. This way of attachment to the Glycoluril U-shape scaffold afforded a rigidified and closed receptor for which the electron-rich TTF pincers are expected to be at a suitable distance for sandwiching neutral guests through donor–acceptor interactions. The efficient complexation ability of this host architecture toward one molecule of tetracyanoquinodimethane derivative (F4-TCNQ) in solution has been demonstrated using cyclic voltammetry and UV-Visible titration methods.
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Fused Glycoluril-tetrathiafulvalene molecular clips as receptors for neutral electron acceptor guests.
Organic Letters, 2014Co-Authors: Yoann Cotelle, Stéphanie Legoupy, Magali Allain, Piétrick HudhommeAbstract:Glycoluril-based molecular clips incorporating tetrathiafulvalene (TTF) sidewalls have been synthesized, and the efficient binding ability in solution of this host architecture toward m-dinitrobenzene through donor–acceptor interaction has been demonstrated.
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Fused Glycoluril-Tetrathiafulvalene Molecular Clips as Receptors for Neutral Electron Acceptor Guests
2014Co-Authors: Yoann Cotelle, Magali Allain, Stéphanie Legoupy, Piétrick HudhommeAbstract:Glycoluril-based molecular clips incorporating tetrathiafulvalene (TTF) sidewalls have been synthesized, and the efficient binding ability in solution of this host architecture toward m-dinitrobenzene through donor–acceptor interaction has been demonstrated