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Rocco Ungaro - One of the best experts on this subject based on the ideXlab platform.
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Calixarenes in molecular recognition
Supramolecular Chemistry: From Molecules to Nanomaterials, 2012Co-Authors: Laura Baldini, Francesco Sansone, Alessandro Casnati, Rocco UngaroAbstract:This chapter summarizes the most important aspects of the chemistry of Calixarenes and their applications in supramolecular chemistry. The first section gives a short summary of the synthesis and conformational properties of Calixarenes and of their functionalization at the phenolic OH groups (lower rim) and at the para-position of the aromatic nuclei (upper rim). The second section covers the properties of native and functionalized Calixarenes (including chiral compounds) as receptors for the selective recognition of neutral molecules, cations, anions, and ion-pairs in the solid state, organic media, and water solution. In the third section, the Calixarenes are viewed as scaffolds for the construction of multivalent ligands able to target biomacromolecules eliciting or inhibiting a biological process. Calixarene glycoclusters, operating as efficient and selective multivalent inhibitors of vegetal and mammalian lectins; peptidoCalixarenes, capable of disrupting protein–protein interactions; and guanidino-Calixarenes, able to target proteins or to condense DNA, acting, in this case, as efficient nonviral vectors for cell transfection, are discussed. When relevant, the use of calixarene receptors and multivalent ligands as active components of sensor devices for the detection of various analytes is also reported. Perspectives for future developments of Calixarenes in supramolecular chemistry and bionanotechnology are indicated. Keywords: Calixarenes; carbohydrate recognition; cavitands; cell transfection; glycoCalixarenes; ion recognition; molecular inclusion; multivalency; peptidoCalixarenes; protein recognition
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Calixarenes from biomimetic receptors to multivalent ligands for biomolecular recognition
New Journal of Chemistry, 2010Co-Authors: Francesco Sansone, Laura Baldini, Alessandro Casnati, Rocco UngaroAbstract:Calixarenes are versatile platforms for the design and synthesis of molecular receptors and multivalent ligands that are able to mimic or affect specific biological functions. This review illustrates examples spanning the recognition of small peptides and carbohydrates to ion transport through membranes, biomimetic catalysis, DNA condensation and cell transfection, protein binding, sensing and inhibition, and gives perspectives for using calixarene macrocycles in bio-supramolecular chemistry.
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partitioning of minor actinides effects of gamma irradiation on the extracting capabilities of a selected calixarene based picolinamide ligand
Radiation Physics and Chemistry, 2007Co-Authors: Mario Mariani, Alessandro Casnati, Elena Macerata, Michele Galletta, A Buttafava, Rocco Ungaro, A Faucitano, Marco GiolaAbstract:Abstract The ligand [3- N -(6-carboxymethylpicolinamide)propyloxy]calix[6]arene ( 1 ) has been selected among a series of calixarene-based picolinamide ligands as a possible candidate to be used in a small-scale process for the An/Ln separation under the option of the advanced reprocessing of irradiated nuclear fuel. In this frame, due to the high radioactivity of the nitric solutions to be treated, the behaviour of the ligand under irradiation conditions is undoubtedly of key importance. Liquid–liquid extraction tests were performed, in order to ascertain the extracting capabilities of the calixarene ligand 1 before and after γ-irradiation. A wide range of absorbed doses was investigated, and the tests were performed both in reactive and inert (N 2 ) atmosphere. The determination of distribution coefficients for actinides and lanthanides, and of the separation factors between elements of the two families was carried out by using γ-spectrometry (as for 241 Am and 152 Eu) and ICP-mass spectrometry (MS) (as for all the lanthanides of interest). Contrarily to what observed in the case of other previously and currently studied ligands [Baaden, M., Berny, F., Muzet, N., Troxler, L., Wipff, G., 2000. In: Lumetta, G., Rogers, R., Gopolan A. (Eds.), Calixarenes for Separation. A.C.S. Symposium Series No. 757. American Chemical Society, Washington, DC, pp. 45–55], the extraction efficiency (distribution coefficients) of the calixarene ligand 1 , increases by a factor of 2–10 after γ-irradiation on a significant range of absorbed doses.
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calixarene based multivalent ligands
Chemical Society Reviews, 2007Co-Authors: Laura Baldini, Francesco Sansone, Alessandro Casnati, Rocco UngaroAbstract:Multivalency is a powerful concept which explains the strong binding observed in biological systems and guides the design and synthesis of ligands for self-assembly and molecular recognition in Chemistry. The phenol–formaldehyde cyclic oligomers, called Calixarenes, have been used as scaffolds for the synthesis of multivalent ligands thanks to the fact that they have a variable number of reactive positions for attaching the ligating functions, well defined conformational properties and, in some cases, cavities of molecular dimensions eventually able to encapsulate guest species. This tutorial review illustrates the fundamental aspects of multivalency and the properties of calixarene-based multivalent ligands in lectin binding and inhibition, DNA condensation and cell transfection, protein surface recognition, self-assembly, crystal engineering, and nanofabrication.
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Calixarenes in action
2000Co-Authors: Luigi Mandolini, Rocco UngaroAbstract:A study of the class of synthetic macrocycles, called Calixarenes. Rather than emphasizing the molecular properties of Calixarenes, it covers in depth their supramolecular functions, demonstrating the peculiar features of Calixarenes as hosts and as platforms for the synthesis of more complex reactors and catalysts. Topics include the use of Calixarenes in: molecular modelling of Calixarenes; non-covalent interactions; crystal engineering; cation recognition; anion recognition; supramolecular devices; new materials; self-assembly processes; and supramolecular catalysis. The book reports, for each topic, the literature critically evaluated by active researchers in the field.
Seiji Shinkai - One of the best experts on this subject based on the ideXlab platform.
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Novel Cavity Design Using Calix[n]arene Skeletons: Toward Molecular Recognition and Metal Binding.
Chemical reviews, 1997Co-Authors: Atsushi Ikeda, Seiji ShinkaiAbstract:Calixarenes are macrocyclic molecules, like crown ethers and cyclodextrins.1-7 Calixarenes made up of phenol and methylene units have many conformational isomers because of two possible rotational modes of the phenol unit: the oxygen-through-theannulus rotation and the para-substituent-throughthe-annulus rotation (Figure 1). The conformational isomers thus yielded afford a great number of unique cavities with the different size and the different shape. Recently, a number of strategies have been exploited by which not only the conformation of calix[4]arenes, but also those of calix[6]arenes and calix[8]arenes, can be immobilized. This means that our group can now design various calixarene-based receptors that show high selectivity for guest molecules and metal cations. In this review article, our group describe novel strategies for cavity design using calix[n]arene skeletons, strategies that are intended to allow complexation of specific molecular targets or metal ions.
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recent topics on functionalization and recognition ability of Calixarenes the third host molecule
Bulletin of the Chemical Society of Japan, 1995Co-Authors: Michinori Takeshita, Seiji ShinkaiAbstract:This review article covers recent topics of a calixarene family concerning their stereochemistry, complexation with metal ions and organic guests, and other topics. As stereochemistry of Calixarenes, the restriction of flipping motions of the composed benzene units of calix[4]-, [5]-, [6]arenes is summarized. In Recognition of Calixarenes, the selective recognition of alkali metal cations utilizing calixcrowns is a main subject in metal cation recognition. Concerning with recognition of metal cations and organic molecules, the ‘reading-out’ systems of recognition phenomena are summarized. The complexation of calix[8]arene with fullerene, which was discovered as serendipity and will be very useful as a new fullerene purification method is also reported.
Alessandro Casnati - One of the best experts on this subject based on the ideXlab platform.
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Moulding Calixarenes for biomacromolecule targeting
Chemical Communications, 2015Co-Authors: Marta Giuliani, Francesco Sansone, Ilaria Morbioli, Alessandro CasnatiAbstract:After their successful use as a preorganized platform for the preparation of receptors for metal ions and small neutral molecules over the last 15 years, Calixarenes are enjoying a renaissance of popularity as scaffolds for ligands that are able to efficiently and selectively target macromolecules such as proteins/enzymes, nucleic acids and lipids. This feature article summarizes the peculiar factors characterizing the calixarene structure and properties, as well as outlines the main rules that can be used to turn such macrocycles into efficient and successful ligands for these classes of biomacromolecules. Factors that affect the multivalent properties of Calixarenes, such as the size, conformation and stereochemical presentation of binding groups or their amphiphilicity and hybrid character, are described in detail with the use of a few selected examples from the literature. Perspectives and applications of these ligands in bionanotechnology and nanomedicine, such as protein sensing and inhibition, gene-delivery, targeted drug-delivery and cell imaging, are also discussed.
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Calixarenes in molecular recognition
Supramolecular Chemistry: From Molecules to Nanomaterials, 2012Co-Authors: Laura Baldini, Francesco Sansone, Alessandro Casnati, Rocco UngaroAbstract:This chapter summarizes the most important aspects of the chemistry of Calixarenes and their applications in supramolecular chemistry. The first section gives a short summary of the synthesis and conformational properties of Calixarenes and of their functionalization at the phenolic OH groups (lower rim) and at the para-position of the aromatic nuclei (upper rim). The second section covers the properties of native and functionalized Calixarenes (including chiral compounds) as receptors for the selective recognition of neutral molecules, cations, anions, and ion-pairs in the solid state, organic media, and water solution. In the third section, the Calixarenes are viewed as scaffolds for the construction of multivalent ligands able to target biomacromolecules eliciting or inhibiting a biological process. Calixarene glycoclusters, operating as efficient and selective multivalent inhibitors of vegetal and mammalian lectins; peptidoCalixarenes, capable of disrupting protein–protein interactions; and guanidino-Calixarenes, able to target proteins or to condense DNA, acting, in this case, as efficient nonviral vectors for cell transfection, are discussed. When relevant, the use of calixarene receptors and multivalent ligands as active components of sensor devices for the detection of various analytes is also reported. Perspectives for future developments of Calixarenes in supramolecular chemistry and bionanotechnology are indicated. Keywords: Calixarenes; carbohydrate recognition; cavitands; cell transfection; glycoCalixarenes; ion recognition; molecular inclusion; multivalency; peptidoCalixarenes; protein recognition
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Calixarenes from biomimetic receptors to multivalent ligands for biomolecular recognition
New Journal of Chemistry, 2010Co-Authors: Francesco Sansone, Laura Baldini, Alessandro Casnati, Rocco UngaroAbstract:Calixarenes are versatile platforms for the design and synthesis of molecular receptors and multivalent ligands that are able to mimic or affect specific biological functions. This review illustrates examples spanning the recognition of small peptides and carbohydrates to ion transport through membranes, biomimetic catalysis, DNA condensation and cell transfection, protein binding, sensing and inhibition, and gives perspectives for using calixarene macrocycles in bio-supramolecular chemistry.
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partitioning of minor actinides effects of gamma irradiation on the extracting capabilities of a selected calixarene based picolinamide ligand
Radiation Physics and Chemistry, 2007Co-Authors: Mario Mariani, Alessandro Casnati, Elena Macerata, Michele Galletta, A Buttafava, Rocco Ungaro, A Faucitano, Marco GiolaAbstract:Abstract The ligand [3- N -(6-carboxymethylpicolinamide)propyloxy]calix[6]arene ( 1 ) has been selected among a series of calixarene-based picolinamide ligands as a possible candidate to be used in a small-scale process for the An/Ln separation under the option of the advanced reprocessing of irradiated nuclear fuel. In this frame, due to the high radioactivity of the nitric solutions to be treated, the behaviour of the ligand under irradiation conditions is undoubtedly of key importance. Liquid–liquid extraction tests were performed, in order to ascertain the extracting capabilities of the calixarene ligand 1 before and after γ-irradiation. A wide range of absorbed doses was investigated, and the tests were performed both in reactive and inert (N 2 ) atmosphere. The determination of distribution coefficients for actinides and lanthanides, and of the separation factors between elements of the two families was carried out by using γ-spectrometry (as for 241 Am and 152 Eu) and ICP-mass spectrometry (MS) (as for all the lanthanides of interest). Contrarily to what observed in the case of other previously and currently studied ligands [Baaden, M., Berny, F., Muzet, N., Troxler, L., Wipff, G., 2000. In: Lumetta, G., Rogers, R., Gopolan A. (Eds.), Calixarenes for Separation. A.C.S. Symposium Series No. 757. American Chemical Society, Washington, DC, pp. 45–55], the extraction efficiency (distribution coefficients) of the calixarene ligand 1 , increases by a factor of 2–10 after γ-irradiation on a significant range of absorbed doses.
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calixarene based multivalent ligands
Chemical Society Reviews, 2007Co-Authors: Laura Baldini, Francesco Sansone, Alessandro Casnati, Rocco UngaroAbstract:Multivalency is a powerful concept which explains the strong binding observed in biological systems and guides the design and synthesis of ligands for self-assembly and molecular recognition in Chemistry. The phenol–formaldehyde cyclic oligomers, called Calixarenes, have been used as scaffolds for the synthesis of multivalent ligands thanks to the fact that they have a variable number of reactive positions for attaching the ligating functions, well defined conformational properties and, in some cases, cavities of molecular dimensions eventually able to encapsulate guest species. This tutorial review illustrates the fundamental aspects of multivalency and the properties of calixarene-based multivalent ligands in lectin binding and inhibition, DNA condensation and cell transfection, protein surface recognition, self-assembly, crystal engineering, and nanofabrication.
Jong Seung Kim - One of the best experts on this subject based on the ideXlab platform.
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revisiting fluorescent Calixarenes from molecular sensors to smart materials
Chemical Reviews, 2019Co-Authors: Rajesh Kumar, Amit Sharma, Hardev Singh, Paolo Suating, Hyeong Seok Kim, Kyoung Sunwoo, Inseob Shim, Bruce C Gibb, Jong Seung KimAbstract:Calix[n]arenes (n = 4, 5, 6, 8) are "chalicelike" phenol-based macrocycles that are among the most fascinating and highly studied scaffolds in supramolecular chemistry. This stems from the functional and tunable diversity at both their upper and lower rims, their preorganized nonpolar cavities and preorganized ion-binding sites, and their well-defined conformations. Conjugation of calixarene scaffolds with various fluorogenic groups has led to the development of smart fluorescent probes that have been utilized as molecular sensors, in bioimaging, for drug and gene delivery, in self-assembly/aggregation, and as smart materials. The fine-tuning and incorporation of different ligating sites in the calix[4]arene scaffold have produced numerous molecular sensors for cations, anions, and biomolecules. Moreover, the aqueous solubility of p-sulfonatocalix[4]arenes has engendered their potential use in drug/gene delivery and enzymatic assays. In addition, because of their strong optical properties, fluorescent calix[4]arenes have been used to develop smart materials, including gels as well as nonlinear optical, organic light-emitting diode, and multiphoton materials. Finally, significant developments in the utility of fluorescent higher Calixarenes have been made for bioapplications. This review critically summarizes the recent advances made in all of these different areas.
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calixarene based chemosensors by means of click chemistry
Chemistry-an Asian Journal, 2014Co-Authors: Miaomiao Song, Zhongyue Sun, Cuiping Han, Demei Tian, Jong Seung KimAbstract:Click chemistry, a new strategy for organic chemistry, has been widely used in the chemical modification of Calixarenes because of its reliability, specificity, biocompatibility, and efficiency. Click-derived triazoles also play a critical role in sensing ions and molecules. This in-depth review provides an overview of calixarene-based chemosensors that incorporate click-derived triazoles, and their three characteristics (chromogenic, fluorescence, and wettability) are reviewed.
Francesco Sansone - One of the best experts on this subject based on the ideXlab platform.
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Moulding Calixarenes for biomacromolecule targeting
Chemical Communications, 2015Co-Authors: Marta Giuliani, Francesco Sansone, Ilaria Morbioli, Alessandro CasnatiAbstract:After their successful use as a preorganized platform for the preparation of receptors for metal ions and small neutral molecules over the last 15 years, Calixarenes are enjoying a renaissance of popularity as scaffolds for ligands that are able to efficiently and selectively target macromolecules such as proteins/enzymes, nucleic acids and lipids. This feature article summarizes the peculiar factors characterizing the calixarene structure and properties, as well as outlines the main rules that can be used to turn such macrocycles into efficient and successful ligands for these classes of biomacromolecules. Factors that affect the multivalent properties of Calixarenes, such as the size, conformation and stereochemical presentation of binding groups or their amphiphilicity and hybrid character, are described in detail with the use of a few selected examples from the literature. Perspectives and applications of these ligands in bionanotechnology and nanomedicine, such as protein sensing and inhibition, gene-delivery, targeted drug-delivery and cell imaging, are also discussed.
-
Calixarenes in molecular recognition
Supramolecular Chemistry: From Molecules to Nanomaterials, 2012Co-Authors: Laura Baldini, Francesco Sansone, Alessandro Casnati, Rocco UngaroAbstract:This chapter summarizes the most important aspects of the chemistry of Calixarenes and their applications in supramolecular chemistry. The first section gives a short summary of the synthesis and conformational properties of Calixarenes and of their functionalization at the phenolic OH groups (lower rim) and at the para-position of the aromatic nuclei (upper rim). The second section covers the properties of native and functionalized Calixarenes (including chiral compounds) as receptors for the selective recognition of neutral molecules, cations, anions, and ion-pairs in the solid state, organic media, and water solution. In the third section, the Calixarenes are viewed as scaffolds for the construction of multivalent ligands able to target biomacromolecules eliciting or inhibiting a biological process. Calixarene glycoclusters, operating as efficient and selective multivalent inhibitors of vegetal and mammalian lectins; peptidoCalixarenes, capable of disrupting protein–protein interactions; and guanidino-Calixarenes, able to target proteins or to condense DNA, acting, in this case, as efficient nonviral vectors for cell transfection, are discussed. When relevant, the use of calixarene receptors and multivalent ligands as active components of sensor devices for the detection of various analytes is also reported. Perspectives for future developments of Calixarenes in supramolecular chemistry and bionanotechnology are indicated. Keywords: Calixarenes; carbohydrate recognition; cavitands; cell transfection; glycoCalixarenes; ion recognition; molecular inclusion; multivalency; peptidoCalixarenes; protein recognition
-
Calixarenes from biomimetic receptors to multivalent ligands for biomolecular recognition
New Journal of Chemistry, 2010Co-Authors: Francesco Sansone, Laura Baldini, Alessandro Casnati, Rocco UngaroAbstract:Calixarenes are versatile platforms for the design and synthesis of molecular receptors and multivalent ligands that are able to mimic or affect specific biological functions. This review illustrates examples spanning the recognition of small peptides and carbohydrates to ion transport through membranes, biomimetic catalysis, DNA condensation and cell transfection, protein binding, sensing and inhibition, and gives perspectives for using calixarene macrocycles in bio-supramolecular chemistry.
-
calixarene based multivalent ligands
Chemical Society Reviews, 2007Co-Authors: Laura Baldini, Francesco Sansone, Alessandro Casnati, Rocco UngaroAbstract:Multivalency is a powerful concept which explains the strong binding observed in biological systems and guides the design and synthesis of ligands for self-assembly and molecular recognition in Chemistry. The phenol–formaldehyde cyclic oligomers, called Calixarenes, have been used as scaffolds for the synthesis of multivalent ligands thanks to the fact that they have a variable number of reactive positions for attaching the ligating functions, well defined conformational properties and, in some cases, cavities of molecular dimensions eventually able to encapsulate guest species. This tutorial review illustrates the fundamental aspects of multivalency and the properties of calixarene-based multivalent ligands in lectin binding and inhibition, DNA condensation and cell transfection, protein surface recognition, self-assembly, crystal engineering, and nanofabrication.
