Journal articles: 'Calixareni'

1

Jose, Princy, and Shobana Menon. "Lower-Rim Substituted Calixarenes and Their Applications." Bioinorganic Chemistry and Applications 2007 (2007): 1–16. http://dx.doi.org/10.1155/2007/65815.

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This review discusses in detail “calixarenes” since their discovery as by-products of the phenol formaldehyde bakelites till the present scenario wherein calixarene has assumed a new dimension in the field of supramolecular chemistry. Extensive literature exists for calixarenes; but herein we have tried to concentrate on the different lower-rim modified calixarenes with their potential applications. An attempt has also been made to critically evaluate the synthesis procedures for different lower-rim substituted calixarenes.

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Mironova, Diana, Vladimir Burilov, Farida Galieva, Mohamed Ali Mohamed Khalifa, Sofia Kleshnina, Alsu Gazalieva, Ramil Nugmanov, Svetlana Solovieva, and Igor Antipin. "Azocalix[4]arene-Rhodamine Supramolecular Hypoxia-Sensitive Systems: A Search for the Best Calixarene Hosts and Rhodamine Guests." Molecules 26, no. 18 (September 7, 2021): 5451. http://dx.doi.org/10.3390/molecules26185451.

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A potential hypoxia-sensitive system host-guest complex of three calixarenes (including two with four anionic carboxyl and sulphonate azo fragments on the upper rim and a newly synthesized bis-azo adduct of calixarene in the cone configuration with azo fragments on the lower rim with the most widespread cationic and zwitterionic rhodamine dyes (123, 6G and B)) was studied using UV-VIS spectrometry and fluorescence as well as 1D and 2D NMR techniques. It was found that all three calixarenes form a complex with rhodamine dyes with a 1:1 composition. The association constants of calixarene-dye complexes with sulfonate calixarenes, especially in the case of tetra-anionic calixarene, turned out to be higher compared with carboxyl calixarene due to the more intense electrostatic interactions. For the first time using an HRESI MS technique, it was shown that the treatment of rhodamine 6G and 123 with sodium dithionite (SDT) produces a non-fluorescent leuco form of the dye, and only rhodamine B can be used with SDT without the occurrence of a side reduction. Moreover, it was identified that in addition to the reduction in the azo groups, SDT causes partial cleavage of the aryl ether bonds. The found features of SDT should be taken into account when SDT is used as an azoreductase mimic.

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Basilotta, Rossella, Deborah Mannino, Alessia Filippone, Giovanna Casili, Angela Prestifilippo, Lorenzo Colarossi, Gabriele Raciti, Emanuela Esposito, and Michela Campolo. "Role of Calixarene in Chemotherapy Delivery Strategies." Molecules 26, no. 13 (June 29, 2021): 3963. http://dx.doi.org/10.3390/molecules26133963.

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Since cancer is a multifactorial disease with a high mortality rate, the study of new therapeutic strategies is one of the main objectives in modern research. Numerous chemotherapeutic agents, although widely used, have the disadvantage of being not very soluble in water or selective towards cancerous cells, with consequent side effects. Therefore, in recent years, a greater interest has emerged in innovative drug delivery systems (DDSs) such as calixarene, a third-generation supramolecular compound. Calixarene and its water-soluble derivatives show good biocompatibility and have low cytotoxicity. Thanks to their chemical–physical characteristics, calixarenes can be easily functionalized, and by itself can encapsulate host molecules forming nanostructures capable of releasing drugs in a controlled way. The encapsulation of anticancer drugs in a calixarene derivate improves their bioavailability and efficacy. Thus, the use of calixarenes as carriers of anticancer drugs could reduce their side effects and increase their affinity towards the target. This review summarizes the numerous research advances regarding the development of calixarene nanoparticles capable of encapsulating various anticancer drugs.

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Lazar, Adina N., Oksana Danylyuk, Kinga Suwinska, and Anthony W. Coleman. "The Structure of the Tetra-Potassium Salt of Calix[4]Arene Dihydroxyphosphonic Acid." Chemistry Journal of Moldova 2, no. 1 (December 2007): 98–101. http://dx.doi.org/10.19261/cjm.2007.02(1).07.

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The solid-state structure of the tri-potassium calix[4]arene dihydroxyphosphonate salt is presented. In this structure, two potassium cations bridge between layers of dimeric calixarene diphosphonate units and two other potassium cations bridge along the face of the layers. The ubiquitous dimeric association of the calixarenes shows the highest interdigitation value so far observed. As expected, the cations are solvated and are complexed exo with respect to calixarene crown. The octahedral coordination sphere of the potassium cations is formed by two phosphonate groups of the calixarenes and four water molecules. Electrostatic forces represent the major element of interaction in the solid-state system.

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Lebrón, José Antonio, Manuel López-López, Clara B. García-Calderón, Ivan V. Rosado, Fernando R. Balestra, Pablo Huertas, Roman V. Rodik, et al. "Multivalent Calixarene-Based Liposomes as Platforms for Gene and Drug Delivery." Pharmaceutics 13, no. 8 (August 12, 2021): 1250. http://dx.doi.org/10.3390/pharmaceutics13081250.

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The formation of calixarene-based liposomes was investigated, and the characterization of these nanostructures was carried out using several techniques. Four amphiphilic calixarenes were used. The length of the hydrophobic chains attached to the lower rim as well as the nature of the polar group present in the upper rim of the calixarenes were varied. The lipid bilayer was formed with one calixarene and with the phospholipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine, DOPE. The cytotoxicity of the liposomes for various cell lines was also studied. From the results obtained, the liposomes formed with the least cytotoxic calixarene, (TEAC12)4, were used as nanocarriers of both nucleic acids and the antineoplastic drug doxorubicin, DOX. Results showed that (TEAC12)4/DOPE/p-EGFP-C1 lipoplexes, of a given composition, can transfect the genetic material, although the transfection efficiency substantially increases in the presence of an additional amount of DOPE as coadjuvant. On the other hand, the (TEAC12)4/DOPE liposomes present a high doxorubicin encapsulation efficiency, and a slow controlled release, which could diminish the side effects of the drug.

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6

Cohen, Yoram, and Sarit Slovak. "Diffusion NMR for the characterization, in solution, of supramolecular systems based on calixarenes, resorcinarenes, and other macrocyclic arenes." Organic Chemistry Frontiers 6, no. 10 (2019): 1705–18. http://dx.doi.org/10.1039/c9qo00329k.

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The use of diffusion NMR in studying calixarenes and other arene-based supramolecular systems is described, emphasizing the pivotal role played by the calixarene community in transforming the methods into a routine tool used in supramolecular chemistry.

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7

Schatz, Jürgen. "Recent Application of ab initio Calculations on Calixarenes and Calixarene Complexes. A Review." Collection of Czechoslovak Chemical Communications 69, no. 6 (2004): 1169–94. http://dx.doi.org/10.1135/cccc20041169.

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In this short review the application of ab initio quantum chemical calculations on calixarenes and calixarene complexes is highlighted. The main focus lies on results obtained mainly during the last 2-3 years. A review with 92 references.

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8

Kalchenko, Vitaly I. "Calixarene receptors of environmentally hazardous and biorelevant molecules and ions." Pure and Applied Chemistry 80, no. 7 (January 1, 2008): 1449–58. http://dx.doi.org/10.1351/pac200880071449.

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In the paper, a report on the rational design of the calixarene receptors bearing ligating, H-donor, H-acceptor fragments at the wide and/or narrow rim of the macrocycle is presented. The calixarenes form supramolecular complexes with various cations, anions, organic molecules, and biomolecules in solution, in the crystalline state and even in the gas phase. The calixarenes or their complexes can be used as materials for radionuclide extraction, construction of chemosensors, and drug design.

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Allen, Hillary F., Kevin D. Daze, Takashi Shimbo, Anne Lai, Catherine A. Musselman, Jennifer K. Sims, Paul A. Wade, Fraser Hof, and Tatiana G. Kutateladze. "Inhibition of histone binding by supramolecular hosts." Biochemical Journal 459, no. 3 (April 11, 2014): 505–12. http://dx.doi.org/10.1042/bj20140145.

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We report a new set of calixarene-based host compounds and show their applicability in characterizing functions of methyllysine-recognizing epigenetic readers. Calixarenes disrupt the association of the PHD finger of CHD4 with a trimethylated, but not an unmodified, histone tail.

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10

Ling, Irene, Alexandre N. Sobolev, and Colin L. Raston. "Controlling the organization of phosphonium cations relative to p-sulfonatocalix[4]arene anions." CrystEngComm 17, no. 7 (2015): 1526–30. http://dx.doi.org/10.1039/c4ce02086c.

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A composite material containing supermolecules of 1,4-bis(triethylammoniomethyl)benzene and p-sulfonated calix[4]arene involves preferential binding of the ammonium moieties in the cavities of two geometrically opposed calixarenes with mono-phosphonium cations arranged in the endo-orientation with respect to the calixarene bilayers, as a multi-layered structure.

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11

SHIN, DONG-MYUNG, DONG-MEE SONG, GEEWON CHUNG, and KYEONGTAE KIM. "COMPLEXATION OF AROMATIC MOLECULES WITH NEW CALIXARENE DERIVATIVES CONTAINING TWO ARYL SULFIDE RINGS." Journal of Nonlinear Optical Physics & Materials 14, no. 04 (December 2005): 513–20. http://dx.doi.org/10.1142/s0218863505002967.

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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.

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12

Ling, Irene, Mohamed Makha, Alexandre N. Sobolev, Yatimah Alias, and Colin L. Raston. "Mapping Out the Diversity of Lanthanide(III) Coordination Complexes Involving p-Sulfonatocalix[4,6]arenes." Australian Journal of Chemistry 73, no. 6 (2020): 570. http://dx.doi.org/10.1071/ch19640.

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Structurally authenticated complexes of the cone-shaped p-sulfonatocalix[4]arene and conformationally flexible p-sulfonatocalix[6]arene devoid of co-ligands/ancillary molecules are limited. Early and late members of the lanthanide series as their trivalent ions, La3+, Er3+, and Yb3+, form complexes from aqueous media under these conditions. For La3+ and Er3+, distinct hydrophobic and hydrophilic bilayers are formed with p-sulfonatocalix[4]arene, whereas for Yb3+, two complexes form that deviate from the well-known bilayer arrangement of calixarenes. Replacing the calixarene with p-sulfonatocalix[6]arene results in a hydrogen-bonded network with alternating hydrophobic–hydrophilic layers associated with primary coordination of Yb3+, with the larger macrocyclic calixarene in a partial cone conformation.

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13

Elsegood, Mark, Lynne Horsburgh, Carl Redshaw, Oliver Rowe, and Simon Teat. "Pillared 2-D MOFs Based on a Lower-Rim Acid-Appended Calix[4]arene." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1226. http://dx.doi.org/10.1107/s2053273314087737.

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Calixarenes have been the focus of intense research study of both their organic and metal-coordinated chemistry over the past twenty or so years. Calixarenes generally have intrinsic cavities in their cone or partial cone structures, often filled with coordinated or non-coordinated solvent of crystallization, or filled with substituents from neighboring calixarene molecules. Much of this research has generated molecular, or zero-dimensional compounds, rather than oligomeric or polymeric materials. The shape and size of the calixarene molecules and complexes has led to their use in separation science, catalysis, imaging, etc. Over the same time period, studies on metal-organic frameworks (MOFs) have also been prominent, driven mainly by the ambition to store gases like hydrogen or trap CO2. Metal ions form nodes and bond to organic spacers which generate a rigid or flexible poly-dimensional framework with pores. This research contribution marries the two fields and incorporates calixarene molecules, with their inherent pores, into MOFs. Solvothermal reactions of the lower-rim functionalized diacid calix[4]arene 25,27-bis(methoxycarboxylic acid)-26,28-dihydroxy-4-tert-butylcalix[4]arene (LH2) with Zn(NO3)2·6H2O and the dipyridyl ligands 4,4′-bipyridyl (4,4′-bipy), 1,2-di(4-pyridyl)ethylene (DPE) or 4,4′-azopyridyl (4,4′-azopy) afforded a series of 2-D structures of the formulae {[Zn(4,4′-bipy)(L)]·2¼DEF}n (1, Fig. 1.), {[Zn2(L)(DPE)]·DEF}n (2) and {[Zn(OH2)2(L)(4,4′-azopy)]·DEF}n (3) (DEF = diethylformamide)1. Figure 1. {[Zn(4,4′-bipy)(L)]·2¼DEF}n (1)

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14

Priyangga, Krisfian Tata Aneka, Yehezkiel Steven Kurniawan, Keisuke Ohto, and Jumina Jumina. "Review on Calixarene Fluorescent Chemosensor Agents for Various Analytes." Journal of Multidisciplinary Applied Natural Science 2, no. 1 (January 15, 2022): 23–40. http://dx.doi.org/10.47352/jmans.2774-3047.101.

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Calixarenes are well-known supramolecular host molecules with versatile applications. Over the past decades, hundreds of selective and sensitive detections of several analytes have been reported by employing calixarenes as the chemosensor agent. The detection and quantification of metal ions and anions are crucial as heavy metal ions are harmful to living organisms, while monitoring anions is pivotal in the environmental samples. On the other hand, detecting and quantifying biomolecules and neutral molecules are critical due to their irreplaceable role in human health. In this review, we summarized the application of calixarenes as the supramolecular chemosensor agent for detecting metal ions, anions, biomolecules, and neutral molecules through fluorescent spectroscopy to give brief information on the design and development of the chemosensor field. This review updates the world with the application of calixarene derivatives as fluorescent chemosensors and challenges researchers to design and develop better chemosensor agents in the future.

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15

Bilyk, Alexander, Annegret K. Hall, Jack M. Harrowfield, Mir Wais Hosseini, Brian W. Skelton, and Allan H. White. "A Unique Rare-Earth Cluster within a Calixarene Sandwich: Parallels in the Chemistry of Cyclosiloxanes and Calixarenes." Australian Journal of Chemistry 53, no. 12 (2000): 895. http://dx.doi.org/10.1071/ch00152.

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Determination of the crystal structure of a complex obtained by the reaction of the dimethyl sulfoxide (dmso) solvate of neodymium(III) nitrate with p-t-butyltetrathiacalix[4]arene in dimethylformamide (dmf) in the presence of base showed a regular, planar cluster of four neodymium atoms bridged by a hydroxyl group to be sandwiched between two fully deprotonated calixarene moieties. The sulfur and oxygen donor atoms of the calixarenes are both involved in coordination to the rare-earth atoms. Both dmf and dmso are found as ligands on neodymium but occupation of the calixarene cavity is by dmf only. The proposed overall stoichiometry of the complex is [Nd4(OH){(p-t-butyltetrathiacalix[4]arene-4H)(dmf)}2(dmf)6(dmso)2](NO3)3.3H2O.

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Zaremba, A., and M. Platonov. "Search of the binding site of the calix[4]arene with the myosin light-chain kinase by molecular dynamics method." Bulletin of Taras Shevchenko National University of Kyiv. Series: Biology 78, no. 2 (2019): 57–61. http://dx.doi.org/10.17721/1728_2748.2019.78.57-61.

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Disruptions of the functional activity of human smooth muscle are associated with a significant number of pathological conditions of the human body. The myosin light-chain kinase is the key enzyme of the signaling cascade of neurohumoral signals in smooth muscle cells. Especially it is important in the long-term tonic contraction. Disruption of its kinase activity can lead to a weakening of the intercellular interaction of the epithelial and endothelial cells, disruption of functioning of the intestinal smooth muscles and vessels, complication of labor activity. At the moment the search for effectors of this enzyme is being carried out. The problem is that most drugs are removed at the general body level due to toxic effects on other tissues (organs) or adverse chemical and physical properties. Such substances require adapters (carriers) devoid of these defects and inert in vivo. The most promising are calixarenes. In this study, the molecular dynamics method was used to determine the stability of the calix [4] arenetetrazulphate complex and the myosin light-chain kinase catalytic domain. Initially, by means of docking, the most favorable position of calixaren was determined; it turned out to be a catalytic kinase pocket. After that, the molecular-dynamic experiment was conducted to determine the energy of interaction. It turned out that the total energy of the interaction is about -300 cJ/mol. This indicates the high stability of the complex. Due the location of the ligand, its effect on the enzymatic activity of the kinase can be assumed, therefore, the use of this calixarene as a drug delivery system seems inappropriate.

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Weigand, Wolfgang, Thomas Weisheit, and Martin Freesmeyer. "Examination of the complexation ability of different calixarene derivatives towards [223Ra]RaCl2 in a hospital radiopharmaceutical laboratory." Nuklearmedizin 57, no. 06 (December 2018): 242–46. http://dx.doi.org/10.3413/nukmed-0933-18-08.

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Summary Aim: In this contribution we investigated the potential transfer of an established method for the synthesis of 223Ra-labelled calixarene complexes to a hospital radiopharmaceutical environment. For this purpose, commercially available [223Ra]RaCl2 solution in pharmaceutical grade (Xofigo®) was reacted with three calixarene derivatives. Methods: A wellestablished two-phase extraction method using a two-phase solvent system was performed for complexation of the radium ions with calixarenes under slightly basic conditions. Moreover, the complexation reaction was conducted in homogenous medium (water / THF) as well as under elevated temperature. Results: The investigated reaction conditions did not allow the isolation of the desired products. Analytical evidence for the presence of radium-calixarene species by means of activity measurement, TLC as well as HPLC could not been proven unambiguously. Conclusion: We address the non-conversion of the educts to the large excess of sodium ions in the used Xofigo® solution, what may explain the hampered reaction for all conducted experiments. Finally the transfer of the published complexation concept into a radiopharmaceutical routine environment was not successful.

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Masoumifeshani, Emran, Michał Chojecki, Dorota Rutkowska-Zbik, and Tatiana Korona. "Association Complexes of Calix[6]arenes with Amino Acids Explained by Energy-Partitioning Methods." Molecules 27, no. 22 (November 16, 2022): 7938. http://dx.doi.org/10.3390/molecules27227938.

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Intermolecular complexes with calixarenes are intriguing because of multiple possibilities of noncovalent binding for both polar and nonpolar molecules, including docking in the calixarene cavity. In this contribution calix[6]arenes interacting with amino acids are studied with an additional aim to show that tools such as symmetry-adapted perturbation theory (SAPT), functional-group SAPT (F-SAPT), and systematic molecular fragmentation (SMF) methods may provide explanations for different numbers of noncovalent bonds and of their varying strength for various calixarene conformers and guest molecules. The partitioning of the interaction energy provides an easy way to identify hydrogen bonds, including those with unconventional hydrogen acceptors, as well as other noncovalent bonds, and to find repulsive destabilizing interactions between functional groups. Various other features can be explained by energy partitioning, such as the red shift of an IR stretching frequency for some hydroxy groups, which arises from their attraction to the phenyl ring of calixarene. Pairs of hydrogen bonds and other noncovalent bonds of similar magnitude found by F-SAPT explain an increase in the stability of both inclusion and outer complexes.

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Vysotsky, Myroslav, Christian Schmidt, and Volker Bohmer. "ChemInform Abstract: Chirality in Calixarenes and Calixarene Assemblies." ChemInform 32, no. 5 (January 30, 2001): no. http://dx.doi.org/10.1002/chin.200105282.

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Islam, Md Monarul, Paris E. Georghiou, Shofiur Rahman, and Takehiko Yamato. "Calix[3]arene-Analogous Metacyclophanes: Synthesis, Structures and Properties with Infinite Potential." Molecules 25, no. 18 (September 14, 2020): 4202. http://dx.doi.org/10.3390/molecules25184202.

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Calixarene-analogous metacyclophanes (CAMs) are a special class of cyclophanes that are cyclic polyaromatic hydrocarbons containing three or more aromatic rings linked by one or more methylene bridging groups. They can be considered to be analogues of calixarenes, since, in both types of molecules, the component aromatic rings are linked by methylene groups, which are meta to each other. Since the prototype or classical calix[4]arene consists of four benzene rings each linked by methylene bridges, which are also meta to each other, it can be considered to be an example of a functionalized [1.1.1.1]metacyclophane. A metacyclophane (MCP) that consists of three individual hydroxyl-group functionalized aromatic rings linked by methylene groups, e.g., a trihydroxy[1.1.1]MCP may therefore, by analogy, be termed in the broadest sense as a “calix[3]arene” or a “calix[3]arene-analogous metacyclophane”. Most of the CAMs reported have been synthesized by fragment coupling approaches. The design, synthesis and development of functionalized CAMs, MCPs, calixarenes and calixarene analogues has been an area of great activity in the past few decades, due their potential applications as molecular receptors, sensors and ligands for metal binding, and for theoretical studies, etc. In this review article, we focus mainly on the synthesis, structure and conformational properties of [1.1.1]CAMs, i.e., “calix[3]arenes” and their analogues, which contain three functionalized aromatic rings and which provide new scaffolds for further explorations in supramolecular and sensor chemistry.

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Tao, Xuchen, Quan Feng, and Hui He. "Preparation of Calixarene-PI Nanofibers and Application as a Selective Adsorbent for Heavy Metal Ions." Journal of Engineered Fibers and Fabrics 13, no. 1 (March 2018): 155892501801300. http://dx.doi.org/10.1177/155892501801300101.

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In order to utilize the adsorption selectivity of calixarenes towards heavy metal ions, calixarene functionalized polyimide (Calix-PI) fibers were prepared by three main synthesis procedures including preparation of the calixarene polyamide acid (Calix-PAA) spinning solution via amidation, fabrication of the Calix-PAA fibers by electrospinning, and preparation of the Calix-PI fibers via thermal imidization on the Calix-PAA fibers. The Calix-PI fibers were characterized by Fourier transform infrared spectroscopy, scanning electronic microscopy and thermogravimetric analysis. The Calix-PI fibers display selective adsorption on Pb(II), which is fit with the pseudo-second-order adsorption kinetics model and the Freundlich adsorption isothermal model. The rate constant of the pseudo-second-order adsorption kinetics model and the maximum Pb(II) uptake have all been calculated. The practical adsorption of Pb(II) on the Calix-PI fibers is mainly attributed to the monolayer chemical adsorption and slightly depended on the physical adsorption.

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Rathore, Rajendra, Sergey V. Lindeman, and Sameh H. Abdelwahed. "Design, Synthesis, Electronic Properties, and X-ray Structural Characterization of Various Modified Electron-Rich Calixarene Derivatives and Their Conversion to Stable Cation Radical Salts." Molecules 27, no. 18 (September 14, 2022): 5994. http://dx.doi.org/10.3390/molecules27185994.

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We have designed and synthesized electron-rich calixarene derivatives, which undergo reversible electrochemical oxidation in a well-accessible potential range that allows the ready preparation and isolation of the corresponding cation radicals. Preparation of mono- or tetra-radical cation can be achieved by using stable aromatic cation-radical salts such as MA+•, MB+•, and NAP+• as selective organic oxidants. The cation radicals of calixarenes are stable indefinitely at ambient temperatures and can be readily characterized by UV-vis-NIR spectroscopy. These cation radicals bind a single molecule of nitric oxide within its cavity with remarkable efficiency.

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Peters, Max Sena, Miao Li, and Thomas Schrader. "Interactions of Calix[n]arenes with Nucleic Acids." Natural Product Communications 7, no. 3 (March 2012): 1934578X1200700. http://dx.doi.org/10.1177/1934578x1200700325.

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DNA interaction with artificial binders is of great interest, especially in light of the broad range of possible biomedical applications. The growing understanding of replication, transcription and translation opened the path for new approaches to target pathological effects at a very early stage. Meanwhile, the competitive binding to nucleic acids by designed molecules, which, for example, block certain sequences for natural binders, such as transcription factors, has become a promising concept in the context of gene therapy. On the other extreme, the transport of nucleic acids over the cell membrane into the nucleus by transfection agents opens the possibility to reprogram protein biosynthesis within host cells. In the past decades several substance classes have been developed for a noncovalent specific DNA binding with predictable biological effects, such as peptide nucleic acids or polyamide ligands. Calixarenes have not received so much attention, although they consist of a compact aromatic core tuneable in size, and allow the introduction of cationic functionalities at their upper and lower rims. Formerly being utilized as receptor moieties due to the possibility of complexating guests in their cavities, calixarenes are now also used as molecular scaffolds for multivalent ligands and are, therefore, suitable tools for cooperative DNA complexation. This review surveys specific supramolecular interactions between calixarene derivatives and nucleic acids, with an emphasis on structural elements in the calixarenes and the biological consequences of their complex formation with DNA strands.

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Alex, Jimi M., Martin L. Rennie, Sylvain Engilberge, Gábor Lehoczki, Hajdu Dorottya, Ádám Fizil, Gyula Batta, and Peter B. Crowley. "Calixarene-mediated assembly of a small antifungal protein." IUCrJ 6, no. 2 (February 5, 2019): 238–47. http://dx.doi.org/10.1107/s2052252519000411.

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Synthetic macrocycles such as calixarenes and cucurbiturils are increasingly applied as mediators of protein assembly and crystallization. The macrocycle can facilitate assembly by providing a surface on which two or more proteins bind simultaneously. This work explores the capacity of the sulfonato-calix[n]arene (sclx n ) series to effect crystallization of PAF, a small, cationic antifungal protein. Co-crystallization with sclx4, sclx6 or sclx8 led to high-resolution crystal structures. In the absence of sclx n , diffraction-quality crystals of PAF were not obtained. Interestingly, all three sclx n were bound to a similar patch on PAF. The largest and most flexible variant, sclx8, yielded a dimer of PAF. Complex formation was evident in solution via NMR and ITC experiments, showing more pronounced effects with increasing macrocycle size. In agreement with the crystal structure, the ITC data suggested that sclx8 acts as a bidentate ligand. The contributions of calixarene size/conformation to protein recognition and assembly are discussed. Finally, it is suggested that the conserved binding site for anionic calixarenes implicates this region of PAF in membrane binding, which is a prerequisite for antifungal activity.

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Shkrabak, O. A., T. O. Veklich, R. V. Rodik, V. I. Kalchenko, and S. O. Kosterin. "Inhibition of plasma membrane Сa(2+),Mg(2+)-АТРase by сalixarene sulfonylamidines. Structure-activity relationship." Ukrainian Biochemical Journal 94, no. 4 (November 10, 2022): 18–35. http://dx.doi.org/10.15407/ubj94.04.018.

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Previously we have already shown that tetrasulfonylamidinecalixarene C-90 inhibited plasma membrane Са2+,Mg2+-АТРаse of smooth muscle cells selectively to other ATPases of plasma membrane. To inhance the inhibitory effect of calixarenes several alkoxycalixarene sulfonylamidines structurally similar to calixarene C-90 were synthesized and their effects on the mentioned enzyme activity, the level of cytoplasmic Ca2+ concentration and hydrodynamic diameter of isolated smooth muscle cells were checked. It was shown that sulfonylamidino groups are crucial for Са2+,Mg2+-АТРаse inhibition, the efficiency of inhibition depends on their quantity and spatial orientation at the upper rim of calixarene macrocycle. Introduction of phenyl or tert-butyl groups into the upper rim and of long alkyl chains into the lower rim led to only slightl increase of inhibition efficiency. The inhibitory effect of studied calixarenes on Са2+,Mg2+-АТРаse correlated with effects on cytosolic Ca2+ concentration and hydrodynamic diameter of smooth muscle cells. The obtained results are important for creation of more effective and selective inhibitors of plasma membrane Са2+,Mg2+-АТРаse as regulators of smooth muscle contractility. Keywords: calixarene sulfonylamidines, intracellular Ca(2+) concentration, plasma membrane Са(2+);Mg(2+)-АТРаse, smooth muscle

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Adhel, Erika, Axel Labattut, Timothée Naret, Diana Dragoe, and Vincent Huc. "A Calix[8]arene-Based Catalyst for Suzuki–Miyaura Couplings with Reduced Pd_Leaching." Catalysts 12, no. 10 (September 22, 2022): 1098. http://dx.doi.org/10.3390/catal12101098.

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Pd-catalysed reactions are amongst the most important in current chemistry. Consequently, very reactive catalysts were developed during the last decades, allowing very high conversions at low catalytic rates. However, decreasing Pd leaching in final products without decreasing catalyst efficiency remains an unsolved issue, especially in the pharma industry. We recently showed that using calixarenes as platforms for Pd-based catalysts constitutes an efficient answer to this concern. In the present work, we show that using these calixarenic platforms in combination with suitably engineered ligands allows for an even more strongly decreased Pd leaching. It thus opens up interesting perspectives for the synthesis of new families of catalysts combining a very high reactivity and a very low Pd leaching in final products.

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27

Suchorski, Yuri, Jochen Gottfriedsen, Rafal Wrobel, Bartosz Strzelczyk, and Helmut Weiss. "Evaluation and X-Ray Induced Modification of the Cerium Oxidation State in Cerium Calixarene Complexes." Solid State Phenomena 128 (October 2007): 115–20. http://dx.doi.org/10.4028/www.scientific.net/ssp.128.115.

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The cerium oxidation state in novel calixarene-supported cerium(IV) β-diketonate complexes [p-tBu-calix[4](OMe)2(O)2]Ce(acac)2 (1) and [p-tBu-calix[4](OMe)2(O)2]Ce(hfac)2 (2), which are a new class of potential precursors for homogeneous oxidative transformations, has been determined using X-ray photoelectron spectroscopy (XPS). Cerium oxidation states between 3.6 and 3.65 were detected, distinctly different from their nominal value of +4. An X-ray induced photoreduction of these compounds was detected. Because of the observed stability of the X-ray modified oxidation state under ambient conditions this effect might be used for a long-standing fine tuning of the Ce oxidation state in cerium calixarenes.

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Burilov, Vladimir, Egor Makarov, Diana Mironova, Elza Sultanova, Islamiya Bilyukova, Kevser Akyol, Vladimir Evtugyn, et al. "Calix[4]arene Polyamine Triazoles: Synthesis, Aggregation and DNA Binding." International Journal of Molecular Sciences 23, no. 23 (November 28, 2022): 14889. http://dx.doi.org/10.3390/ijms232314889.

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Artificial gene delivery systems are in great demand from both scientific and practical biomedical points of view. In this paper, we present the synthesis of a new click chemistry calix[4]arene precursor with free lower rim and new water-soluble calixarene triazoles with 12 amino-groups on the upper rim (one with free phenol hydroxyl groups and two another containing four butyl or tetradecyl fragments). Aggregation in the series of amino-triazole calixarenes of different lipophilicity (calixarene with free phenol hydroxyl groups or butyl and tetradecyl fragments on the lower rim) was studied using dynamic light scattering and fluorescent pyrene probe. It was found that calix[4]arene with a free lower rim, like alkyl-substituted butyl calix[4]arene, forms stable submicron aggregates 150–200 nm in size, while the more lipophilic tetradecyl –substituted calix[4]arene forms micellar aggregates19 nm in size. Using UV-Vis spectroscopy, fluorimetry and CD, it was shown that amino-triazole calix[4]arenes bind to calf thymus DNA by classical intercalation. According to DLS and TEM data, all studied macrocycles cause significant DNA compaction, forming stable nanoparticles 50–20 nm in size. Among all studied calix[4]arenes the most lipophilic tetradecyl one proved to be the best for both binding and compaction of DNA.

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XIE, D., and C. D. GUTSCHE. "ChemInform Abstract: Calixarenes. Part 46. Calixarene Anhydrides as Useful Synthetic Intermediates." ChemInform 28, no. 33 (August 3, 2010): no. http://dx.doi.org/10.1002/chin.199733124.

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30

Marradi, Marco, Stefano Cicchi, Francesco Sansone, Alessandro Casnati, and Andrea Goti. "Low-generation dendrimers with a calixarene core and based on a chiral C 2-symmetric pyrrolidine as iminosugar mimics." Beilstein Journal of Organic Chemistry 8 (June 26, 2012): 951–57. http://dx.doi.org/10.3762/bjoc.8.107.

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The preparation of low-generation dendrimers based on a simple calix[4]arene scaffold by insertion of the iminosugar-analogue C 2-symmetric 3,4-dihydroxypyrrolidine is described. This methodology allows a rapid incorporation of a considerable number of iminosugar-like moieties in a reduced volume and in a well-defined geometry. The inclusion of alkali-metal ions (sodium and potassium) in the polar cavity defined by the acetamide moieties at the lower rim of the calixarene was demonstrated, which allows also the rigidification of the dendrimer structure and the iminosugar presentation in the clusters. The combination of the supramolecular properties of calixarenes with the advantage of a dendrimeric presentation of repetitive units opens up the possibility of generating well-defined multivalent and multifaceted systems with more complex and/or biologically relevant iminosugars.

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31

Vaňura, Petr, and Ivan Stibor. "Extraction of Alkaline and Alkaline-Earth Metal Cations at Synergistic Action of Bis[undecahydro-7,8-dicarbaundecaborato(2-)]cobaltate(1-) and Substituted Calix[n]arenes in Nitrobenzene." Collection of Czechoslovak Chemical Communications 63, no. 12 (1998): 2009–14. http://dx.doi.org/10.1135/cccc19982009.

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The extraction of alkaline and alkaline-earth metal cations at synergistic action of bis[undecahydro-7,8-dicarbaundecaborato(2-)]cobaltate(1-) and substituted calix[n]arenes (n = 4 and 6) in nitrobenzene was investigated. It was found that the lower-rim-substituted calix[4]arene with four (diethylcarbamoyl)methyl groups extracts calcium, strontium and barium in the systems under study much better than calixarenes which do not contain amide groups. Synergistic factor values log S(Ca) = 7, log S(Sr) = 5.5 and log S(Ba) = 5.4 were found. The competition of K+ and Na+ in the extraction of strontium is much lower than in analogous systems containing crown ethers. The addition of calixarene causes a synergistic effect in the extraction of sodium and an antagonistic effect in the extraction of cesium.

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32

Glennon, Jeremy D., Elizabeth Horne, Patricia O'Sullivan, Sharon Hutchinson, M. Anthony McKervey, and Stephen J. Harris. "Transition Metal Ion Complexation and Extraction by Hydroxamate Functionalised p-Tert-Butylcalix[4]Arenes." Metal-Based Drugs 1, no. 2-3 (January 1, 1994): 151–60. http://dx.doi.org/10.1155/mbd.1994.151.

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The functionalisation of macrocyclic p-tertbutylcalix[4]arenes at the lower rim with hydroxamic acid and proline hydroxamic acid groups gives the calixarenes chelating properties similar to siderophores. The H1 NMR spectrum of p-tertbutylcalix[4]arene tetrahydroxamic acid shows a broad band at 10.8 ppm in DMSO-d6 attributed to NHOH protons. Diffuse reflectance spectral analysis of PVC membranes containing the calixarene hydroxamic acids show absorption bands at 485 nm and 504 nm following contact with aqueous solutions of Fe(III) and V(V) respectively. The pH dependency of this extractive selectivity is examined for Fe(III), Co(II), Pb(II), Mn(II), Cu(II) and Ni(II) using a solid phase extraction approach. Spectrophotometric evidence for the complexation of Cu(II) in methanol by p-tertbutylcalix[4]arene tetraproline acid is also provided.

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33

Cay, Seydahmet, Serkan Sayin, and Mehmet Soner Engin. "Calix[4]arene Embedded Polyamide Supported Liquid Membrane for Separation of Heavy Metals from Aqueous Solutions." Turkish Journal of Agriculture - Food Science and Technology 8, no. 2 (February 27, 2020): 387. http://dx.doi.org/10.24925/turjaf.v8i2.387-391.3064.

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In this study, we aimed to prepare new calixaren embedded mercapto groups supported liquid membranes and to use them in the transport of heavy metals. For this purpose 5,11,17,23-tetra-tert-butyl-25,27-bis(3-thiol-1-oxypropane)-26,28-dihydroxylcalix[4]arene was synthesized. The synthesized calixarene compounds were fully characterized by spectroscopic and the other techniques. The prepared compounds were supported polyamide liquid membranes and obtained calix[4]aren embedded supported liquid membranes (C@PSMs). The characterization of C@PSM was carried out by FTIR, TGA and elemental analysis techniques. Transport experiments were carried out with Pb(II), Cd(II) and Zn(II) as trace metals, to transport from donor phase to accept phase. From the results, it was calculated flux (J) and recovery (RF) values. The affinity (the percentage of metal ion transferred from the source solution) of a PIM towards a range of divalent cations was found to follow the order Zn(II)> Cd(II)> Pb(II).

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34

Memon, Shahabuddin, D. Max Roundhill, and Mustafa Yilmaz. "Remediation and Liquid-Liquid Phase Transfer Extraction of Chromium(VI). A Review." Collection of Czechoslovak Chemical Communications 69, no. 6 (2004): 1231–50. http://dx.doi.org/10.1135/cccc20041231.

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Chromium(VI) is a widely used industrial chemical, and is generally considered to pose a greatest human health risk because it is more toxic, more soluble, and more mobile than chromium(III). Workers in industries that use chromium, in particular stainless steel welding, chromate production, chromium plating, and chrome pigment industries, where exposure via inhalation of aerosols is primarily to hexavalent chromium, are at increased risk of chromium effects. In this article we demonstrate various studies regarding remediation methods in particular liquid-liquid extraction of chromate and dichromate anions with various functionalized calixarenes. This review article briefly discusses various molecular designs of calixarene-type macrocycles for chromium(VI) oxoanion recognition, and gives examples on the relationship between structure and selectivity. The article does not, however, attempt to cover all of the different approaches to chromium(VI) extraction. A review with 73 references.

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35

Supian, Faridah Lisa, Wong Yeong Yi, Nur Farah Nadia Abd Karim, Afiq Radzwan, Darvina Lim Choo Kheng, and Abdullah Faisal Al Naim. "THE MOLECULAR BEHAVIORS OF CALIXARENES AT THE AIR-WATER INTERFACE: DENSITY FUNCTIONAL THEORY, SURFACE PRESSURE, POTENTIAL, AND EFFECTIVE DIPOLE MOMENT." Malaysian Journal of Science 41, no. 3 (October 31, 2022): 63–68. http://dx.doi.org/10.22452/mjs.vol41no3.9.

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This study examined the behaviors of Langmuir-Blodgett ultrathin calixarene films at the air-water interface. The Langmuir trough was used to estimate the surface pressure, surface potential, and effective dipole moment of two calixarenes, namely, calix[4]arene (THC4) and calix[8]arene (THC8). The band gap was determined using the density functional theory (DFT). The DFT simulation gave a band gap of 2.28 eV for THC4, confirming that THC4 was an insulator. The surface pressure isotherms of THC4 and THC8 yielded the expected molecular behavior from the gaseous to the solid phases. THC4 and THC8 showed a perpendicular and a parallel orientation in the air-water subphase, respectively. The ∆Vmax values of TCH4 and THC 8 were 205 mV and 141mV, respectively, and their µ﬩max values were 0.147 D and 0.088 D, respectively.

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36

Wang, Jianshe, and C. David Gutsche. "ChemInform Abstract: Calixarenes. Part 54. Synthesis and Structure of Calixarene-Fullerene Dyads." ChemInform 32, no. 1 (January 2, 2001): no. http://dx.doi.org/10.1002/chin.200101130.

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37

Azahari, Noor Azyyati, Faridah Lisa Supian, Tim H. Richardson, and Syed Abdul Malik. "Properties of Calix4-Lead(Pb) Films Using Langmuir-Blodgett (LB) Technique as an Application of Ion Sensor." Advanced Materials Research 895 (February 2014): 8–11. http://dx.doi.org/10.4028/www.scientific.net/amr.895.8.

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Calixarenes are promising compounds to be used as ionophores and for molecular recognition. Their ability to form Langmuir and Langmuir-Blodgett (LB) films is of great interest in order to obtain small sensor devices which incorporate an active nanometric film. Calix[4]arene (Calix4) has been used in this work and its ability to form Langmuir films has been shown. Calix4 forms monolayers but at higher compressions tends to form multilayers. The presence of ions in the subphase, as lead chloride salt solutions, leads to some changes in the surface pressure-area (П-A) isotherms and surface potential-area (ΔV-A) isotherms. The effective dipole moments (μ) of the calixarene molecules in the uncomplexed and complexed states has been calculated from the ΔV values by using Helmholtz equation. Some characteristics of the films and mean molecular area have been deduced from the isotherms graph.

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38

Daze, Kevin D., Catherine E. Jones, Brandin J. Lilgert, Cory S. Beshara, and Fraser Hof. "Determining the effects of salt, buffer, and temperature on the complexation of methylated ammonium ions and methyllysines by sulfonated calixarenes." Canadian Journal of Chemistry 91, no. 11 (November 2013): 1072–76. http://dx.doi.org/10.1139/cjc-2013-0186.

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Sulfonated calixarenes have long been used as effective binders of ammonium ions in aqueous solution. Recently, the utility of sulfonated calix[4]arenes and calix[6]arenes as specific agents for binding biologically important ammonium ions, and especially post-translationally methylated amino acids, peptides, and proteins, has suggested that they might have important roles to play in the control and understanding of biological pathways. We report here binding data in various buffer systems that attempt to shed light on the roles of buffer and salt in the recognition processes of these hosts. We also report studies on trimethyllysine binding that explore the effects of near physiological salt concentrations and temperatures. These studies provide an understanding of disparate data on these systems and also demonstrate the ability of a sulfonated calixarene to bind trimethyllysine strongly under aqueous conditions that closely replicate the salt concentrations, pH, and temperature of the human body.

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39

Delaigue, Xavier, Jack M. Harrowfield, M. Wais Hosseini, Mauro Mocerino, Brian W. Skelton, and Allan H. White. "'Soft' Calixarenes–Structural Aspects of Calixarene Allyl Ethers and of Thiacalixarene Synthesis." Australian Journal of Chemistry 51, no. 2 (1998): 111. http://dx.doi.org/10.1071/c97095.

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Syntheses and room-temperature single-crystal X-ray structure determinations are recorded for an array of p-t-butylcalix[n]arenes, n = 4 or 6, diversely functionalized at the phenolic oxygen atoms: the 1,3-diallyl 2,4-dimethyl ether for n = 4 (1), the hexaallyl ether for n = 6 (2), and the 1,3-dibenzyl 2,4-bis(dimethylthiocarbamoyl) derivative for n = 4 (3), with a view to establishing ligand baseline conformations for subsequent metal complexation studies, and for exploring any inclusion properties. Compound (1) is monoclinic, P21/c, a 16·751(9), b 20·772(7), c 27·91(1) Å, β 99·39(4)°, Z = 8, conventional R on |F| being 0·060 for No 4396 'observed' (I > 3σ(I )) reflections. Compound (2) is triclinic, P-1, a 19·63(2), b 14·57(2), c 14·188(9) Å, α 107·84(8), β 93·26(7), γ 99·48(10)°, Z = 2, R 0·067 for No 7315. Compound (3), as its methanol monosolvate, is triclinic, P-1, a 15·592(4), b 15·17(3), c 14·31(2) Å, α 88·8(1), β 64·3(1), γ 75·7(1)°, Z = 2, R 0·076 for No 3802. The conformation of (1) is similar to that previously established for an analogue in which two of the t-butyl groups were absent; the conformation of (2) is that of a flattened 1,2,3-alternate form, the asymmetric unit being a pair of half (centrosymmetric) dimers; the conformation of (3) is 1,3-alternate.

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40

Arimura, Takashi, Seiji Shinkai, Tsutomu Matsuda, Yoshimi Hirata, Hiroshi Satoh, and Osamu Manabe. "Fries Rearrangement in Calixarene Esters: A New Entry for the Synthesis ofp-Substituted Calixarenes." Bulletin of the Chemical Society of Japan 61, no. 10 (October 1988): 3733–34. http://dx.doi.org/10.1246/bcsj.61.3733.

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41

Shevchuk, Sergei V., Elena A. Alexeeva, Natalia V. Rusakova, Yurii V. Korovin, Valerii A. Bacherikov, and Andrei I. Gren. "Some new properties of calixarenes: the luminescence of four lanthanide ions in calixarene complexes." Mendeleev Communications 8, no. 3 (January 1998): 112–13. http://dx.doi.org/10.1070/mc1998v008n03abeh000932.

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42

Neri, Placido, Alessandra Bottino, Corrada Geraci, and Mario Piattelli. "Synthesis of glycidyl calixarenes, versatile substrates for the preparation of chiral calixarene-based ligands." Tetrahedron: Asymmetry 7, no. 1 (January 1996): 17–20. http://dx.doi.org/10.1016/0957-4166(95)00410-6.

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43

Yamada, Manabu, Muniyappan Rajiv Gandhi, Kazuhiko Akimoto, and Fumio Hamada. "Crystal structure of a supramolecular lithium complex of p-tert-butylcalix[4]arene." Acta Crystallographica Section E Crystallographic Communications 74, no. 5 (April 17, 2018): 575–79. http://dx.doi.org/10.1107/s2056989018001834.

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Crystals of a supramolecular lithium complex with a calix[4]arene derivative, namely tetramethanollithium 5,11,17,23-tetra-tert-butyl-25,26,27-trihydroxy-28-oxidocalix[4]arene methanol monosolvate, [Li(CH3OH)4](C44H55O4)·CH3OH or [Li(CH3OH)4]+·(calix[4]arene−)]·CH3OH (where calix[4]arene− represents a mono-anion species because of deprotonation of one H atom of the calixarene hydroxy groups), were obtained from p-tert-butylcalix[4]arene reacted with LiH in tetrahydrofuran, followed by recrystallization from methanol. The asymmetric unit comprises one mono-anionic calixarene molecule, one Li+ cation coordinated to four methanol molecules, and one methanol molecule included in the calixarene cavity. The calixarene molecule maintains a cone conformation by intramolecular hydrogen bonding between one phenoxide (–O−) and three pendent calixarene hydroxy groups (–OH). The coordinated methanol molecules around the metal cation play a significant role in forming the supramolecular assembly. The crystal structure of this assembly is stabilized by three sets of intermolecular interactions: (i) hydrogen bonds involving the –OH and –O− moieties of the calixarene molecules, the –OH groups of the coordinated methanol molecules, and the –OH group of the methanol molecule included in the calixarene cavity; (ii) C—H...π interactions between the calixarene molecules and/or the coordinated methanol molecules; (iii) O—H...π interactions between the calixarene molecule and the included methanol molecule.

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44

Ferguson, George, Alan J. Lough, Anna Notti, Sebastiano Pappalardo, Melchiorre F. Parisi, and Giuseppe Resnati. "Synthesis and ESI-MS Alkali Metal Ion Binding Selectivities of Cone, Partial Cone, and 1,3-Alternate 1,3-Bis(α-picolyloxy)-p-tert-butylcalix[4]arene Crown-6 and 1,1'-Binaphthalene-2,2'-diyl Crown-6 Conformers." Collection of Czechoslovak Chemical Communications 69, no. 5 (2004): 1109–25. http://dx.doi.org/10.1135/cccc20041109.

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The syntheses of 1,3-bis(α-picolyloxy)-p-tert-butylcalix[4]arene crown-6 and 1,1'-binaphthalene-2,2'-diyl crown-6 title conformers have been achieved by two complementary synthetic strategies, which differ in the order in which the polyether loop and the pendant picolyl groups are introduced. The structure and conformation of all new compounds have been firmly established by NMR spectroscopy, and further proven by X-ray analysis for the intermediate p-tert-butyl-25,27-(1,1'-binaphthalene-2,2'-diyl-crown-6)-26,28-dihydroxycalix[4]arene. Within each set of conformers, the nature of the polyether chain has little or no influence on the overall conformation of the calixarene platform. The alkali metal ion binding selectivities of the two series of calixarenes have been evaluated in competitive complexation experiments by electrospray ionization mass spectrometry. In the p-tert-butylcalix[4]arene crown-6 series, partial cone and 1,3-alternate conformers show a peak selectivity for the larger Cs+ ions, while the cone one preferentially binds the smaller Na+ ions. On the other hand, the cone and 1,3-alternate binaphthyl-containing analogues show a preference for Na+ ions, the partial cone being quite unselective.

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45

Burilov, Vladimir, Aigul Fatykhova, Diana Mironova, Elza Sultanova, Ramil Nugmanov, Alina Artemenko, Anastasia Volodina, et al. "Oxyethylated Fluoresceine—(thia)calix[4]arene Conjugates: Synthesis and Visible-Light Photoredox Catalysis in Water–Organic Media." Molecules 28, no. 1 (December 28, 2022): 261. http://dx.doi.org/10.3390/molecules28010261.

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Fluorescent derivatives attract the attention of researchers for their use as sensors, photocatalysts and for the creation of functional materials. In order to create amphiphilic fluorescent derivatives of calixarenes, a fluorescein derivative containing oligoethylene glycol and propargyl groups was obtained. The resulting fluorescein derivative was introduced into three different (thia)calix[4]arene azide derivatives. For all synthesized compounds, the luminescence quantum yields have been established in different solvents. Using UV-visible spectroscopy, dynamic light scattering, as well as transmission and confocal microscopy, aggregation of macrocycles was studied. It was evaluated that calixarene derivatives with alkyl substituents form spherical aggregates, while symmetrical tetrafluorescein-containing thiacalix[4]arene forms extended worm-like aggregates. The macrocycle containing tetradecyl fragments was found to be the most efficient in photoredox ipso-oxidation of phenylboronic acid. In addition, it was shown that in a number of different electron donors (NEt3, DABCO and iPr2EtN), the photoredox ipso-oxidation proceeds best with triethylamine. It has been shown that a low molecular weight surfactant Triton-X100 can also improve the photocatalytic abilities of an oligoethylene glycol fluorescein derivative, thus showing the importance of a combination of micellar and photoredox catalysis.

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46

Bezzu, C. Grazia, Madeleine Helliwell, Benson M. Kariuki, and Neil B. McKeown. "Synthesis and crystal structure of a novel phthalocyanine-calixarene conjugate." Journal of Porphyrins and Phthalocyanines 15, no. 07n08 (July 2011): 686–90. http://dx.doi.org/10.1142/s1088424611003628.

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We report the synthesis and crystal structure of a novel phthalocyanine-calixarene conjugate (Pc-Calix) derived from a calixarene-based phthalonitrile (Pn-Calix). Crystal structures confirm the retention of the full cone configuration of the calixarene unit, which is thus suitable for the binding of appropriate chemical species. This new conjugate may find application as a molecular sensor in which the calixarene acts as the binding site and the perturbations of the optical properties of the phthalocyanine reports the presence of the binding species.

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47

SHEVCHUK, S. V., E. A. ALEXEEVA, N. V. RUSAKOVA, Y. V. KOROVIN, V. A. BACHERIKOV, and A. I. GREN. "ChemInform Abstract: Some New Properties of Calixarenes: The Luminescence of Four Lanthanide Ions in Calixarene Complexes." ChemInform 29, no. 43 (June 19, 2010): no. http://dx.doi.org/10.1002/chin.199843024.

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48

Martin, Adam D., Emma Houlihan, Natalie Morellini, Paul K. Eggers, Eliza James, Keith A. Stubbs, Alan R. Harvey, Melinda Fitzgerald, Colin L. Raston, and Sarah A. Dunlop. "Synthesis and Toxicology ofp-Phosphonic Acid Calixarenes and O-Alkylated Analogues as Potential Calixarene-Based Phospholipids." ChemPlusChem 77, no. 4 (March 1, 2012): 308–13. http://dx.doi.org/10.1002/cplu.201100081.

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49

Tan, Ri Hong. "Function and Application of Calixarene Derivatives." Advanced Materials Research 887-888 (February 2014): 647–50. http://dx.doi.org/10.4028/www.scientific.net/amr.887-888.647.

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Calixarene is the third generation of the main compound. Its molecular recognition, simulation enzyme catalysis, molecular catalysis, analytical chemistry, self-assembly, and other areas of research have made great progress. calixarene represent a well-known family of macrocyclic molecules with broad range of potential applications in engineering materials fields. calixarene derivatives for simulating biological system, or in the form of new drug molecules targeting molecule reaction vessel, molecular switches, etc.; Under certain conditions because some new calixarene derivatives with the liquid crystal properties, so some new type of liquid crystal materials can be screened and prepared.

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50

Tang, Wei Ping, and Ming Yang Su. "Calixarene-Based Fluorescent Chemosensors for Metal Ions via Clicking." Applied Mechanics and Materials 687-691 (November 2014): 4223–27. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.4223.

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Calixarene-based fluorenscent chemosenors, owing to its simplicity, high sensitivity and high detection limits for metal ions in biology and the environment, has been received much attention. Via cliking, calixarene derivations has the group of triazoles, which can bind to metol ions, but also can be modified by various fluorophores. This in-depth review provides an overview of calixarene-based fluorescent chemosensors for metal ions via clicking.

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Journal articles on the topic 'Calixareni'

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