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Hasuck Kim - One of the best experts on this subject based on the ideXlab platform.
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Voltammetric studies of thiacalix[4]Arene and p-tert-butylthiacalix[4]Arene and their analytical application
Electrochimica Acta, 2004Co-Authors: Tae Hyun Kim, Jae Kwang Lee, Ju Han Bok, Jong Seung Kim, Hasuck KimAbstract:The electrochemical properties of thiacalix[4]Arene (TCA) and p-tert-butylthiacalix[4]Arene (BuTCA) in the presence of various metal ions were investigated by voltammetry in organic and aqueous acetonitrile solution (pH 8). Their behavior were closely related to the complex formation by entrapping metal ions into the cavity of host molecules, and were compared with the results with calix[4]Arenes. Thiacalix[4]Arenes showed better binding ability towards transition metal ions than alkali or alkaline earth metal ions.
Tomoki Ogoshi - One of the best experts on this subject based on the ideXlab platform.
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Coumarin-containing pillar[5]Arenes as multifunctional liquid crystal macrocycles
'American Chemical Society (ACS)', 2020Co-Authors: Concellón Alberto, Tomoki Ogoshi, Romero Pilar, Marcos Mercedes, Barberá Joaquín, Sánchez-somolinos Carlos, Mizobata Masayuki, Serrano, José Luis, Barrio, Jesús DelAbstract:Liquid crystal macrocycles (LCMs) combine the unique properties of liquid crystals with those associated with macrocyclic compounds—shape persistence and the capability of hosting small molecules. Herein, we investigate the grafting of coumarin-containing promesogenic moieties to pillar[5]Arene as a strategy to obtain multifunctional LCMs. Pillar[5]Arenes containing 10 and 30 coumarin units are glassy materials with nematic mesomorphism. Moreover, the coumarin moieties afford the pillar[5]Arene derivatives with enhanced film-forming and photoresponsive properties. Photodimerization of the coumarin moieties results in cross-linked polymer networks, which can be used as alignment layers. Therefore, liquid-crystal coumarin-containing pillar[5]Arenes represent a significant addition to the family of LCMs and may become useful for the development of engineered, hierarchical structures and materials.J.D.B. acknowledges MINECO, FSE, and FEDER for funding through projects RYC-2015-18471 (Ramón y Cajal program) and CTQ2017-84087-R. T.O. acknowledges funding from JST CREST. C.S.-S. acknowledges MINECO for funding through project BIO2017-84246-C2-1-R, Gobierno de Aragón for project LMP150_18, and FEDER (EU). J.L.S acknowledges MINECO for funding through project PGC2018-097583-B-I00, FEDER, and Gobierno de Aragón (Research Group E47_17R). The authors thank access to the services of CEQMA (nuclear magnetic resonance, mass spectra, and thermal analysis) of the Universidad de Zaragoza-CSIC. A.C. thanks MINECO for a PhD fellowship.Peer reviewe
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pillar shaped macrocyclic hosts pillar n Arenes new key players for supramolecular chemistry
Chemical Reviews, 2016Co-Authors: Tomoki Ogoshi, Tada-aki Yamagishi, Yoshiaki NakamotoAbstract:In 2008, we reported a new class of pillar-shaped macrocyclic hosts, known as “pillar[n]Arenes”. Today, pillar[n]Arenes are recognized as key players in supramolecular chemistry because of their facile synthesis, unique pillar shape, versatile functionality, interesting host–guest properties, and original supramolecular assembly characteristics, which have resulted in numerous electrochemical and biomedical material applications. In this Review, we have provided historical background to macrocyclic chemistry, followed by a detailed discussion of the fundamental properties of pillar[n]Arenes, including their synthesis, structure, and host–guest properties. Furthermore, we have discussed the applications of pillar[n]Arenes to materials science, as well as their applications in supramolecular chemistry, in terms of their fundamental properties. Finally, we have described the future perspectives of pillar[n]Arene chemistry. We hope that this Review will provide a useful reference for researchers working in th...
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Conversion from pillar[5]Arene to pillar[6-15]Arenes by ring expansion and encapsulation of C60 by pillar[n]Arenes with nanosize cavities.
Organic letters, 2014Co-Authors: Tomoki Ogoshi, Tada-aki Yamagishi, Naosuke Ueshima, Fumiyasu Sakakibara, Takeharu HainoAbstract:Conversion of ring size from pillar[5]Arene to pillar[6–15]Arenes and isolation of pillar[n]Arene homologues (n = 11–13) with known pillar[n]Arene homologues (n = 6–10) are demonstrated. Pillar[10]Arene formed the most stable host–guest complex with C60 among the pillar[5–14]Arenes.
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pillar 5 and pillar 6 Arene based supramolecular assemblies built by using their cavity size dependent host guest interactions
Chemical Communications, 2014Co-Authors: Tomoki Ogoshi, Tada-aki YamagishiAbstract:Pillar[n]Arenes, which we first synthesized and named in 2008, are new pillar-shaped macrocyclic hosts. Pillar[n]Arene homologues with n = 5–10 have already been synthesized, but the cyclic pentamers, i.e., pillar[5]Arenes, and cyclic hexamers, i.e., pillar[6]Arenes, have been most widely used because these can be obtained in good yields. To date, nearly all pillar[n]Arene-based supramolecular assemblies have been constructed using pillar[5]- and pillar[6]Arene scaffolds. In this feature article, we describe supramolecular assemblies built using host–guest interactions depending on the cavity sizes of pillar[5]- and pillar[6]Arenes. We first discuss the effects of the type of substituents on the rims of pillar[5]- and pillar[6]Arenes on their solubilities, functionalities and host–guest properties. We then discuss supramolecular assemblies based on their host–guest properties and pillar-shaped architectures.
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Clickable Di- and Tetrafunctionalized Pillar[n]Arenes (n = 5, 6) by Oxidation–Reduction of Pillar[n]Arene Units
The Journal of organic chemistry, 2012Co-Authors: Tomoki Ogoshi, Daiki Yamafuji, Daisuke Kotera, Takamichi Aoki, Shuhei Fujinami, Tada-aki YamagishiAbstract:We report a new route for the selective synthesis of di- and tetrafunctionalized pillarArenes via oxidation and reduction of the pillarArene units. Hypervalent-iodine oxidation of perethylated pillar[5]Arene afforded pillar[5]Arene derivatives containing one benzoquinone unit and two benzoquinones at the A,B- and A,C-units. A pillar[6]Arene derivative containing one benzoquinone unit was also synthesized. Reduction of the benzoquinone units yielded position-selective di- and tetrahydroxylated pillarArene derivatives. This methodology avoids the generation of many constitutional isomers and overcomes the isolation problem of numerous constitutional isomers. From these hydroxylated pillarArenes, Huisgen reaction-based clickable di- and tetraalkynylated pillar[5]Arenes were prepared. Because of the highly selective and reactive nature of Huisgen alkyne-azide cycloaddition, these pillar[5]Arenes can serve as key compounds for a large library of di- and tetrafunctionalized pillarArenes. Based on these di- and tetrafunctionalized pillar[5]Arenes as key compounds, fluorescent sensors were created by the modification of di- and tetrapyrene moieties via Huisgen-type click reactions.
David N. Reinhoudt - One of the best experts on this subject based on the ideXlab platform.
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Conjugation, immunoreactivity, and immunogenicity of calix[4]Arenes; model study to potential calix[4]Arene-based Ac3+ chelators.
Bioconjugate chemistry, 1999Co-Authors: Willem Verboom, Marcel H.b. Grote Gansey, Annemarie S. De Haan, E.s. Bos, David N. ReinhoudtAbstract:For the development of calix[4]Arene-based radiotherapeutic agents, the conjugation to biomolecules and immunogenicity in mice of potential 225Ac3+-chelating calix[4]Arenes were studied. A calix[4]Arene triethyl ester isothiocyanate and a bis(calix[4]Arene) hexacarboxylic acid, containing a masked thiol functionality, were used in conjugation experiments to a mouse monoclonal antibody and serum albumins. All characterization techniques indicate that only the calix[4]Arene carboxylic acid is successfully conjugated to the biomolecules. The immunoreactivity of the conjugates is not impaired when up to 6 equiv of calixArene are bound to the monoclonal antibody. Animal tests indicated that the immunogenicity toward the calix[4]Arene is strongly influenced by the nature of the carrier, the dosage, and the injection method. No immune response occurred when a homologous carrier was used or when a heterologous carrier was applied at a dosage of 10 μg per immunization via intravenous injection. Under all other conditions, the presence of antibodies directed against the calix[4]Arene was demonstrated. Thus, for the application in radioimmunotherapy, the conjugation of a calix[4]Arene to a humanized antibody will probably not lead to an immune response, and the immunoreactivity will not be disturbed.
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Combination of calix[4]Arenes and resorcin[4]Arenes for the complexation of steroids
The Journal of Organic Chemistry, 1996Co-Authors: Irene Higler, Peter Timmerman, Willem Verboom, David N. ReinhoudtAbstract:Receptor molecules with large cavities synthesized by the combination of building blocks that already possess a cavity, viz. calix[4]Arenes and resorcin[4]Arenes, are described. These receptor molecules are synthesized by reaction of one or two upper rim 1,2-difunctionalized calix[4]Arene fragments oriented either endo or exo toward a cavitand unit. The endo:exo ratio depends on the substituents at the 3- and 4-positions of the calix[4]Arenes. These novel receptor molecules complex steroids with association constants of (0.9−9.5) × 102 M-1 in CDCl3.
Tada-aki Yamagishi - One of the best experts on this subject based on the ideXlab platform.
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pillar shaped macrocyclic hosts pillar n Arenes new key players for supramolecular chemistry
Chemical Reviews, 2016Co-Authors: Tomoki Ogoshi, Tada-aki Yamagishi, Yoshiaki NakamotoAbstract:In 2008, we reported a new class of pillar-shaped macrocyclic hosts, known as “pillar[n]Arenes”. Today, pillar[n]Arenes are recognized as key players in supramolecular chemistry because of their facile synthesis, unique pillar shape, versatile functionality, interesting host–guest properties, and original supramolecular assembly characteristics, which have resulted in numerous electrochemical and biomedical material applications. In this Review, we have provided historical background to macrocyclic chemistry, followed by a detailed discussion of the fundamental properties of pillar[n]Arenes, including their synthesis, structure, and host–guest properties. Furthermore, we have discussed the applications of pillar[n]Arenes to materials science, as well as their applications in supramolecular chemistry, in terms of their fundamental properties. Finally, we have described the future perspectives of pillar[n]Arene chemistry. We hope that this Review will provide a useful reference for researchers working in th...
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Conversion from pillar[5]Arene to pillar[6-15]Arenes by ring expansion and encapsulation of C60 by pillar[n]Arenes with nanosize cavities.
Organic letters, 2014Co-Authors: Tomoki Ogoshi, Tada-aki Yamagishi, Naosuke Ueshima, Fumiyasu Sakakibara, Takeharu HainoAbstract:Conversion of ring size from pillar[5]Arene to pillar[6–15]Arenes and isolation of pillar[n]Arene homologues (n = 11–13) with known pillar[n]Arene homologues (n = 6–10) are demonstrated. Pillar[10]Arene formed the most stable host–guest complex with C60 among the pillar[5–14]Arenes.
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pillar 5 and pillar 6 Arene based supramolecular assemblies built by using their cavity size dependent host guest interactions
Chemical Communications, 2014Co-Authors: Tomoki Ogoshi, Tada-aki YamagishiAbstract:Pillar[n]Arenes, which we first synthesized and named in 2008, are new pillar-shaped macrocyclic hosts. Pillar[n]Arene homologues with n = 5–10 have already been synthesized, but the cyclic pentamers, i.e., pillar[5]Arenes, and cyclic hexamers, i.e., pillar[6]Arenes, have been most widely used because these can be obtained in good yields. To date, nearly all pillar[n]Arene-based supramolecular assemblies have been constructed using pillar[5]- and pillar[6]Arene scaffolds. In this feature article, we describe supramolecular assemblies built using host–guest interactions depending on the cavity sizes of pillar[5]- and pillar[6]Arenes. We first discuss the effects of the type of substituents on the rims of pillar[5]- and pillar[6]Arenes on their solubilities, functionalities and host–guest properties. We then discuss supramolecular assemblies based on their host–guest properties and pillar-shaped architectures.
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Clickable Di- and Tetrafunctionalized Pillar[n]Arenes (n = 5, 6) by Oxidation–Reduction of Pillar[n]Arene Units
The Journal of organic chemistry, 2012Co-Authors: Tomoki Ogoshi, Daiki Yamafuji, Daisuke Kotera, Takamichi Aoki, Shuhei Fujinami, Tada-aki YamagishiAbstract:We report a new route for the selective synthesis of di- and tetrafunctionalized pillarArenes via oxidation and reduction of the pillarArene units. Hypervalent-iodine oxidation of perethylated pillar[5]Arene afforded pillar[5]Arene derivatives containing one benzoquinone unit and two benzoquinones at the A,B- and A,C-units. A pillar[6]Arene derivative containing one benzoquinone unit was also synthesized. Reduction of the benzoquinone units yielded position-selective di- and tetrahydroxylated pillarArene derivatives. This methodology avoids the generation of many constitutional isomers and overcomes the isolation problem of numerous constitutional isomers. From these hydroxylated pillarArenes, Huisgen reaction-based clickable di- and tetraalkynylated pillar[5]Arenes were prepared. Because of the highly selective and reactive nature of Huisgen alkyne-azide cycloaddition, these pillar[5]Arenes can serve as key compounds for a large library of di- and tetrafunctionalized pillarArenes. Based on these di- and tetrafunctionalized pillar[5]Arenes as key compounds, fluorescent sensors were created by the modification of di- and tetrapyrene moieties via Huisgen-type click reactions.
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High-yield diastereoselective synthesis of planar chiral [2]- and [3]rotaxanes constructed from per-ethylated pillar[5]Arene and pyridinium derivatives.
Chemistry (Weinheim an der Bergstrasse Germany), 2012Co-Authors: Tomoki Ogoshi, Daiki Yamafuji, Takamichi Aoki, Tada-aki Yamagishi, Keisuke Kitajima, Yoshihiro Hayashi, Susumu KawauchiAbstract:Planar chiral [2]- and [3]rotaxanes constructed from pillar[5]Arenes as wheels and pyridinium derivatives as axles were obtained in high yield using click reactions. The process of rotaxane formation was diastereoselective; the obtained [2]rotaxane was a racemic mixture consisting of (pS, pS, pS, pS, pS) and (pR, pR, pR, pR, pR) forms of the per-ethylated pillar[5]Arene (C2) wheel, and other possible types of the [2]rotaxane did not form. Isolation of the enantiopure [2]rotaxanes with one axle through (pS, pS, pS, pS, pS)-C2 or (pR, pR, pR, pR, pR)-C2 wheels was accomplished. Furthermore, pillar[5]Arene-based [3]rotaxane was successfully synthesized by attachment of two pseudo [2]rotaxanes onto a bifunctional linker. [3]Rotaxane formed in a 1:2:1 mixture with one axle threaded through two (pS, pS, pS, pS, pS)-C2, one (pS, pS, pS, pS, pS)-C2 and one (pR, pR, pR, pR, pR)-C2 (meso form), or two (pR, pR, pR, pR, pR)-C2 wheels. The [3]rotaxane enantiomers and the meso form were successfully isolated using appropriate chiral HPLC column chromatography. The procedure developed in this study is the starting point for the creation of pillar[5]Arene-based interlocked molecules.
Tae Hyun Kim - One of the best experts on this subject based on the ideXlab platform.
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Voltammetric studies of thiacalix[4]Arene and p-tert-butylthiacalix[4]Arene and their analytical application
Electrochimica Acta, 2004Co-Authors: Tae Hyun Kim, Jae Kwang Lee, Ju Han Bok, Jong Seung Kim, Hasuck KimAbstract:The electrochemical properties of thiacalix[4]Arene (TCA) and p-tert-butylthiacalix[4]Arene (BuTCA) in the presence of various metal ions were investigated by voltammetry in organic and aqueous acetonitrile solution (pH 8). Their behavior were closely related to the complex formation by entrapping metal ions into the cavity of host molecules, and were compared with the results with calix[4]Arenes. Thiacalix[4]Arenes showed better binding ability towards transition metal ions than alkali or alkaline earth metal ions.