Calixarene Derivatives Research Articles

カリックスアレーンを基体とした新規イオン交換樹脂の開発

カリックスアレーンカルボン酸誘導体を含有する3種の新規イオン交換樹脂を開発し, 金属の吸着挙動について, バッチ法とカラム法により検討した。カリックス [4] アレーンテトラ酢酸誘導体を含有する樹脂の金属選択性はPb (II) ≫Cu (II) >Zn (II) ≧Ni (II) ≧Co (II) であった。これらカリックスアレーン樹脂の金属に対する選択性などの吸着挙動は, 金属との錯形成に携わるカリックスアレーン部位を抽出剤とするカリックスアレーン誘導体の抽出挙動と多くの点で類似し, 抽出性能を保持して樹脂化されたと考えられる。鉛の充填容量は, 抽出剤としての化学量論 (カリックスアレーン: 鉛=1: 2) と同様になるような樹脂中のカリックスアレーン部位の柔軟性とともに, 単位樹脂重量あたりのカリックス [4] アレーン含有量が大きく関与することが分かった。調製した3種類のカリックス [4] アレーン樹脂による鉛の飽和充填容量は, メチレン架橋型樹脂>ポリアリルアミン担持型樹脂>含浸型樹脂の順となった。また, 鉛と亜鉛のクロマト分離で両者が効率的に分離された。カリックス [4] アレーンテトラ酢酸誘導体を抽出剤として用いた場合と同様に, ナトリウムイオン共存系において含浸樹脂は金属吸着能が向上することが分かった。

Fabrication of Calixarene Derivative Optical Waveguide Using Two-Photon Assisted Polymerization Method

Calixarene derivative optical waveguides have been fabricated by the two-photon assisted polymerization method. The calixarene derivative has excellent in thermal stability and transparency as an optical material. The two-photon assisted polymerization method is a maskless and on-demand process, and thus the various forms of optical waveguides can be fabricated by scanning a monomer thin film with the focal point of the laser beam. Fabrications of not only straight waveguides but also branched waveguides were demonstrated by this method.

Polycationic calix[8]arenes able to recognize and neutralize heparin

A mutual induced fit mechanism is responsible for the exceptional complexation performances exhibited by calix[8]arene polycations towards heparin. The recognition process was studied in comparison with two other heparin antagonists: protamine and polylysine. The arrangement of multiple functional groups on the flexible macrocyclic scaffold of calix[8]arene, with respect to the conformationally rigid protamine and low ordered polylysine, allowed a mutual adaptability between calixarene polycations and heparin, significantly enhancing the recognition performances. Fluorescence, NMR titration, and activated partial thromboplastin time (aPTT) experiments confirmed that these calixarene derivatives have a very high specificity and affinity towards heparin neutralization as in aqueous solution as in blood. Analogous results were obtained with low molecular weight heparin (LMWH) whose effect protamine is unable to completely reverse.

Synthesis and characterization of calixarene derivatives as resist materials for electron-beam lithography

This article describes the electron-beam resist properties of a class of calixarene derivatives for high-resolution electron-beam lithography. The derivatives, which are based on a calix[4]resorcinarene framework, are unique in that the bridging carbon is functionalized with a long chain (C11) alkyl group. Our studies reveal that the electron-beam sensitivity of the calix[4]resorcinarenes is markedly lower than a standard calix[6]arene material, consistent with the increase in sensitivity that is observed with the number of monomers for these systems. Comparison of the sensitivity of the calix[4]resorcinarenes with four member calix[4]arenes from the literature reveals very similar values, indicating that chemical modification at the bridging carbon has no appreciable effect on sensitivity. The minimum linewidth resolution of the calix[4]resorcinarenes under our experimental conditions was found to be approximately 50nm at a threshold line dose of 65nC∕cm. Our results also demonstrate the ability to chemically modify calixarene compounds at the bridging carbon position while maintaining electron-beam sensitivity. These findings are intended to open avenues for more extensive modification schemes in developing resist materials for high-resolution electron-beam lithography.

Synthesis and characterization of Sn(IV) complexes of lower rim 1,3-diacid derivative of calix[4]arene and their protective effects on tissue oxidative stress and essential metal concentration in lead exposed male Wistar rats

The two Sn(IV) complexes synthesized using calix[4]arene-1,3-di-acid derivative were characterized by analytical, 1H, 13C and 119Sn NMR, matrix assisted laser desorption ionization mass, and 119Sn Mossbauer techniques and found that the complexes are tetranuclear possessing structurally two different types of tin centers. These complexes were evaluated for their protective value against blood and tissue oxidative stress in lead exposed male albino rats of Wistar strain. The results suggest that the two tin complexes significantly protect changes in lead induced biochemical variables indicative of heme synthesis pathway and exhibit only moderate effect on tissue oxidative stress. The beneficial effects could be attributed mainly to the ability of Sn(IV) complexes in preventing absorption of lead to the target sites/tissues.

COMPLEXATION OF AROMATIC MOLECULES WITH NEW CALIXARENE DERIVATIVES CONTAINING TWO ARYL SULFIDE RINGS

The cuplike structure of calix[4]arenes is one of the most attractive features, which has been observed both in the solid state and in solution. The newly synthesized 5,11,17,23-tetrakis(3-mercaptopropyl)calix[4]arene (1) and 25,26,27,28-tetrakis(5-mercaptopenthoxy)calix[4]arene containing aryl sulfide rings (2), have four alkyl thiol linkages, which allow the calixarenes to attach onto the gold surface. Surface plasmon resonance (SPR) spectroscopy allows us to monitor the binding of calixarene derivatives on the gold surface. The 1 and 2 bind very effectively on the gold surface and self-assembled layers of 1 and 2 produce significant change in SPR signals in 30 min. Calixarenes layers are used as platforms for molecular recognition, where complementary binding sites are easily and selectively introduced. The aromatic molecules used in this study are anthracene, pyrene, coronene and rubrene. The host-guest properties of these aromatic molecules and the calixarene cavity exhibit selectivity of these aromatic molecules. The anthracene, pyrene and coronene have moderate binding affinity to the cavity, and the rubrene does not bind at all.

Preparation and properties of calix[4]arene-based epoxy resins

Calix[4]arene macrocycles are the subject for increasing interest in the field of supramolecular chemistry and hostguest chemistry as basic skeletons for the synthesis of host compounds for ions or neutral molecules. Although quite a large number of reports exists on the molecular calix[4] arenes, those on polymeric precursors are limited. Recently, calix[4]arene-based polymers have just begun to receive attention, as these new polymers may then be processed into materials suitable for the chemical sensor devices such as ion selective electrodes and filtration/extraction membranes. There is some structural analogy between polymeric linear phenolic novolak molecules and calixarenes which could also be called ‘cyclic phenol resin’. Thus it seems promising to further enhance the sensitivity of calixarene derivatives by applying various techniques, which are generally used to reduce the required dose of commonly used novolak resin. Up to now, this method has not been applied to the non polymeric class of calixarenes. In the microelectronic process, the smallest obtainable structure size as well as the line edge roughness is strongly influenced by the size of the typical novolak based polymeric resist molecules. Therefore, the search for prospective nonpolymeric resist materials has become a high interest. In this paper, various glycidyl calix[4]arene derivatives were prepared using ECH under different conditions, and their curing behavior and thermal properties were examined using epoxy systems with 4,4'-diaminodiphenylmethane and boron trifluoride-isopropylamine as a crosslinker and a cationic catalyst, respectively.

Investigation of Metal Ion Complexation of π-Coordinate Calixarene Derivatives by Electrospray-Ionization Mass Spectrometry

Complexation of π-coordinate calix[4]arene derivatives toward soft metal ions, silver and thallium (I) ions, has been studied by electrospray-ionization mass spectrometry. Competitive metal–ion complexation of three calix[4]arene derivatives demonstrates a significant effect of olefinic substituents and its location on the silver ion complexation, but there was no effect of them on the thallium ion complexation. The stability constants for the metal ion complexes of the calixarene derivatives in methanol have been successfully determined by a mass-spectrometric method using 18-crown-6 as the reference ligand.

Solvation Effect of Guest, Supramolecular Host, and Host−Guest Compounds on the Thermodynamic Selectivity of Calix(4)arene Derivatives and Soft Metal Cations

This paper reports thermodynamic data for the transfer of calixarene derivatives and their metal-ion complexes in dipolar aprotic solvents. These data are used to assess the effect of solvation of these compounds on the selective complexation shown by these macrocycles for soft metal cations in different media. Thus, solubilities and derived Gibbs energies of solution of 5,11,17,23-tetra-tert-butyl[25,27-bis(hydroxyl)-26,28-bis(ethylthioethoxy)]calix(4)arene, 1, and 5,11,17,23-tetra-tert-butyl-[25,27-bis(ethylenethanoate)-26,28-bis(ethylthioethoxy)]-calix(4)arene, 2, in various solvents at 298.15 K are reported. Solvation of these ligands in one medium relative to another is analyzed from their standard transfer Gibbs energies using acetonitrile as the reference solvent. These data are combined with transfer enthalpies (derived from standard solution enthalpies obtained calorimetrically) to calculate the corresponding entropies of transfer of these calix(4)arene derivatives from acetonitrile to methanol and N,N-dimethylformamide. As far as the metal-ion salts (silver and mercury) in their free and complex forms are concerned, standard solution enthalpies were determined in acetonitrile, methanol, and N,N-dimethylformamide. These data are used to derive their transfer enthalpies from one medium to another. It is concluded that the extent of complexation of these macrocycles with soft metal cations is controlled by not only the solvation changes that the free cation undergoes in moving from one medium to another but also those for the ligand and its complex cation in these solvents.

Synthesis of Thiourea‐Bridged Cluster Glycoside Calixarenes

Thiourea‐bridged peracetylated glycoside calixarenes have been smoothly synthesized by the addition reactions of tetraacetylglycosyl isothiocyanates with amidoamine derivatives of calix[4]resorcinarene and p‐tert‐butylcalix[n]arenas (n=6, 8) in high yields (40–75%). All the glycoside‐containing calixarenes were characterized by 1H NMR, IR spectroscopy, and elemental analysis.

A Tetrathiafulvalene-appended Calix[4]arene: Synthesis and Electrochemical Characterization

A tetrathiafulvalene-appended calixarene derivative 3 was synthesized by the reaction of dibromide calixarene 1 with a TTF-thiolate derivative. A preliminary electrochemical study of 3 was carried out along with the X-ray structural characterization of the starting dibromide calixarene 1.

Silver-ion redox sensing based on colloid formation by gallate ester derivatives

Plasmon absorption of silver colloid, which was formed by reduction of silver ion with compounds bearing gallate ester groups in ethanol, was observed by absorption spectroscopy. The time-dependent absorption of silver colloid was found, which shows that the silver colloid is unstable and easy to aggregate. It seemed that a calixarene derivative bearing two gallate ester groups was the most suitable for determining silver ion. In order to prevent the silver colloid aggregation, poly( N-vinylpyrrolidone) (PVP) was added into the solution at a constant time after the preparation of sample solutions. In the calibration graph, the absorbance increased with increasing silver ion concentration, especially in the concentration range of 2.00 × 10 −6 to 1.00 × 10 −5 M. It is possible to determine silver ion concentrations using this method.

Solvent Control on the Selective, Nonselective, and Absent Response of a Partially Substituted Lower Rim Calix(4)arene Derivative for Soft Metal Cations (Mercury(II) and Silver(I)). Structural and Thermodynamic Studies

The solvent control on the ability of a partially substituted lower rim calix(4)arene derivative 5,11,17,23,tetra-tert-butyl[25,27-bis(hydroxy)-26,28-bis(ethylthioethoxy)]-calix(4)arene, 1 to host soft metal cations (Hg(II) and Ag(I)) is demonstrated through 1H NMR, electrochemical (conductance measurements), and thermodynamic characterization of the complexation process in a wide variety of solvents. Solvent-ligand interactions were assessed from 1H NMR measurements involving 1 and various solvents in CDCl3. Thus, the formation of a 1:1 1-CH3CN adduct is reported. As far as metal cations are concerned, depending on the medium their complexation with 1 was only observed for Hg(II) and Ag(I). Thus, in acetonitrile, 1 is more selective for Hg(II) relative to Ag(I) by a factor of 2.2 x 10(3). In methanol the selectivity is reversed to an extent that the affinity of 1 for Ag(I) is 1.4 x 10(3) higher than that for Hg(II). However, 1 is unable to recognize selectively these cations in N,N-dimethylformamide while in propylene carbonate the ability of 1 to interact with these cations is lost. An outstanding feature of thermodynamics emerges when an assessment is made of the ligand effect on the complexation of these cations and analogues calix(4)arene derivatives. Thus, in acetonitrile the thermodynamics of cation complexation by the hydrophilic cavity of a calix(4)arene containing mixed pendant groups is built up from thermodynamic data for the same process involving derivatives with common functionalities at the narrow rim. This is a unique example of the additive contribution of pendant arms in the field of thermodynamics of calixarene chemistry.

A Calix(4)arene Pyridine Derivative and Its Monomeric Component: Structural and Thermodynamic Aspects of Their Complexation with Metal Cations

The interaction of a calix(4)arene derivative, namely 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetra[2-(4-pyridyl)methoxy]calix(4)arene, 1a, and its monomeric component, p-tert-butylphenoxy-4-pyridine, 1b, with metal cations has been investigated in acetonitrile and methanol. (1)H NMR measurements carried out in CD(3)CN show the primary role played by the pyridyl nitrogens in their complexation with metal cations. Conductance measurements demonstrated that for all cations (except mercury) the composition of the metal ion complexes of 1a is 1:1 (ligand:metal cation). However, 1a hosts two mercury cations per unit of ligand. For the monomer 1b, complexes of 2:1 (ligand:metal cation) stoichiometries are formed with the exception of Pb(2+) (1:1 composition). The thermodynamics of complexation of these systems are reported in acetonitrile. Data in methanol are limited to stability constant values for mercury(II) and these ligands. This paper demonstrates for the first time that thermodynamic data for the complexation of the monomeric component of the ligand and metal cations contribute significantly to the interpretation of systems involving cation-calixarene interactions in solution.

Calixarene derivative as a tool for highly sensitive detection and oriented immobilization of proteins in a microarray format through noncovalent molecular interaction

One important factor in fabricating protein microarray is to immobilize proteins without losing their activity on a solid phase. To keep them functional, it is necessary to immobilize proteins in a way that preserve their folded structural integrity. In a previous study, we developed novel Calixarene derivatives for the immobilization of proteins on the surface of a glass slide (1). In this study, we compared the sensitivity and the specificity of the linker molecules with those of five other protein attachment agents on glass slides using a prostate-specific antigen and its antibodies as a model system. The Calixcrown-coated protein chip showed a superior sensitivity and a much lower detection limit than those chips prepared by other methods. When we tested the capability of Calixcrown to immobilize antibody molecules, it appeared that Calixcrown makes arrangement of antibody be more regular with the vertical orientation than the covalent-bond agent. We also observed that the Calixcrown chip could be used for the diagnostic application with clinical samples from prostate cancer and HIV patients. Finally, we applied the Calixcrown chip using an antibody microarray to identify up- or down-regulated proteins in specific tissue and detected several up- or down-regulated proteins from a rat liver by administering toxin. Thus, the Calixcrown chip can be used as a powerful tool with a wide range of applications, including protein-protein interaction, protein-DNA interaction, and an enzyme activity assay.

Selective transfer of Ag + at the water|1,2-dichloroethane interface facilitated by complex formation with a calixarene derivative

The facilitated transfer of silver, Ag +, has been studied at the Interface between Two Immiscible Electrolyte Solutions (ITIES). The transfer was achieved with the assistance of a calixarene-based silver ionophore. An investigation of the mechanistic details of the transfer was conducted using cyclic voltammetry at both micro and macro liquid|liquid interfaces. The mechanism was found to follow a Transfer by Interfacial Complexation (TIC)/Transfer by Organic phase Complexation (TOC) mechanism. The complex stoichiometry was found to shift from 1:1 to 1:2, metal:ligand, with increasing ionophore concentration. The logarithms of the complex association constants, log β 1 o and log β 2 o , were estimated at 12.4 and 14.5, respectively. The charge transfer current was also found to be limited by diffusion of the transferring species and was unchanged by the presence of a range of interferents. The system thus shows promise for selective analytical applications.

Novel Synthesis of p‐t‐Butylcalix[n]arenes Bearing Ethylene Glycol Ether Chains.

Abstract An approach for the synthesis of calixarene derivatives 3a–d, which contain ethylene glycol ether units at the lower rim in moderate yields, is described. The above compounds have been achieved by treating p‐Butylcalix[n]arenes 1a–b (n = 6, 8) with chloroacetate 2a–b of 2‐methoxyethanol and 2‐(2‐butoxyethoxy)ethanol in the system of K2CO3/KI/acetone.

Diels–Alder reactions of bis(spirodienone) derivatives of calix[4]arene with acetylenes: highly regio- and stereoselective synthesis of bisbicyclo[2.2.2]octenone derivatives

Highly regio- and stereoselective Diels–Alder reactions of bis(spirodienone) derivatives of calix[4]arene with acetylenes that provide easy access to bisbicyclo[2.2.2]octenones are described.

Selective Ion Transport and Complexation in Layer-by-Layer Assemblies ofp-Sulfonato- calix[n]arenes and Cationic Polyelectrolytes

The first study of ion transport across self-assembled multilayered films of p-sulfonato-calix[n]arenes and poly(vinyl amine) (PVA) is presented. The films are prepared by the alternate electrostatic layer-by-layer assembly of the anionic calixarenes and cationic PVA on porous polyacrylonitrile (PAN) supports. We use tetra-p-sulfonato-calix[4]arene (calix4), hexa-p-sulfonato-ca-lix[6]arene (calix6), and octa-p-sulfonato-calix[8]arene (calix8) as the calixarenes. Ultraviolet (UV) studies indicate that dipping solutions of pH 6.8, without a supporting electrolyte, are most suited for film preparation. Calix8 is adsorbed in higher concentrations per layer than calix6 or calix4, probably because desorption is less pronounced. The permeation rates, P R s, of monovalent alkali-metal chlorides (Li, Na. K, Cs), magnesium chloride, divalent transition-metal chlorides (Ni, Cu, Zn), trivalent lanthanide chlorides (La, Ce, Pr, Sm), and sodium sulfate across the calix4/PVA, calix6/PVA, and calix8/PVA membranes are studied and compared with the corresponding P R values across a poly(styrene sulfonate) (PSS)/PVA multilayer membrane prepared under the same conditions. The P R values of the alkali-metal salts are between 4 and 17 x 10 - 6 cm s - 1 , those of magnesium chloride and the transition-metal salts are 0.2-1.3 x 10 - 6 cm s - 1 , and those of the lanthanide salts are about 0.1 x 10 - 6 cm s - 1 . Possible origins for the large differences are discussed. Ion transport is first of all controlled by electrostatic effects such as Donnan rejection of di- and trivalent ions in the membrane, but metal-ion complexation with the calixarene derivatives also plays a role. Complexation occurs especially between Li + or Na + and calix4, Mg 2 + , or Cu 2 + and calix6, Cu 2 + , Zn 2 + , or the lanthanide ions and calix8. Divalent sulfate ions are found to replace the calixarene polyanions in the membrane. UV studies of the permeate solutions indicate that calix4 especially is displaced during sulfate permeation.

Anion-Binding Calixarene Receptors: Synthesis, Microstructure, and Effect on Properties of Polyether Electrolytes

In the present paper, a novel lithium-conducting polymer electrolyte, based on the low molecular weight dimethoxy poly(ethylene oxide) matrix as well as high molecular weight poly(ethylene oxide), is studied. New calixarene derivatives have been designed, synthesized, and successfully applied as neutral anion-binding receptors in the electrolytes, what could be of interest in the search for new sensors as well as for enhancing electrolytic functionality in energy-storage devices. Herein, details regarding synthesis and structural properties of all compounds incorporated in the polyether system are presented and discussed. The effect of supramolecular additives on physical (e.g., the charge-carriers transport mechanism, mechanical and thermal properties, or degree of crystallinity) and chemical (e.g., ion-receptor ion-matrix interactions) characteristics of polymer electrolyte is investigated in terms of differential scanning calorimetry, Fourier-transform IR spectroscopy, and impedance spectroscopy result...