Providing Natural Water Structure Surrounding Highly Mobile Maltose Groups Conjugated with Polyrotaxanes

Hirose, Hiroaki; Sano, Hikaru; Mizutani, Goro; Eguchi, Masaru; Ooya, Tooru; Yui, Nobuhiko

doi:10.1295/polymj.pj2006017

Cited by 8 publications

(1 citation statement)

References 14 publications

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“…Since the discovery of cyclodextrin-containing polyrotaxanes by Harada et al, − many attractive concepts and materials originated from their unique structures and functions have been hitherto reported, e.g., stimuli-responsive systems, insulated molecular wires, and polyrotaxane networks . While the polyrotaxanes have long been synthesized by the end-capping of the axle termini of the corresponding polypseudorotaxanes, the end-capping is still a difficult task due to the strong dethreading inclination of the axle from the polypseudorotaxane during the end-capping process, preventing the high yielding synthesis.…”

Section: Introductionmentioning

confidence: 99%

One-Pot Synthesis of Native and Permethylated α-Cyclodextrin-Containing Polyrotaxanes in Water

et al. 2009

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Efficient one-pot synthesis in water of polyrotaxanes, with native and permethylated α-cyclodextrins (α-CD and PMe α-CD) as the wheel components, is described. The procedure involves initial mixing of α-CDs and an amine-terminated linear polymer, which acts as the axle, by sonication and subsequent addition of an end-capping agent for the axle terminal amino groups. The polyrotaxanes were prepared by mixing the axle and wheel components by sonication for 30 min at room temperature and standing overnight if necessary, followed by treatment with a bulky isocyanate in water at 0 °C for an hour. Both amine-terminated polytetrahydrofuran (ATPT) and poly(ethylene glycol) (ATPEG) afforded the corresponding polyrotaxanes (PRXs) in good yields (27−49%) in the case of a native α-CD wheel. The coverage ratio of the axle component with the wheel component of the PRXs ranged from 85% to 96% when the molecular weight of the axle was M n 1000−1800, while it was 54% when the axle was long (M n 7700). The polyrotaxanes (PMePRXs) with PMe α-CD and ATPT were similarly obtained in high yields. In this case, the yield of the PMePRXs was unusually high (66 and 69%) when a higher molecular weight axle (M n 4100 and 7100, respectively) was used. The formation of a PMePRX from ATPEG axle proceeded with low efficiency. The present work provides the first synthesis of polyrotaxanes with PMe α-CD in solution.

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Section: Introductionmentioning

confidence: 99%

One-Pot Synthesis of Native and Permethylated α-Cyclodextrin-Containing Polyrotaxanes in Water

et al. 2009

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Molecular Switches and Machines with Mechanical Bonds

Bruns¹

2016

The Nature of the Mechanical Bond

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Emerging Biomedical Functions through ‘Mobile’ Polyrotaxanes

Yui

2011

Supramolecular Polymer Chemistry

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Biological systems including cells and tissues in living bodies are complex, hierarchical, and dynamic, and they always inspire us to design materials for possible applications. These structures are basically constructed from the appropriate building blocks via various intermolecular forces such as van der Waals interactions, hydrogen bonds, electrostatic interactions, and sometimes hydrophobic effects in water, and are directly adapted to performing a variety of functions such as intercellular signal transduction through plasma membranes, intracellular metabolism triggered by cytoplasmic calcium increase, and cellular proliferations [1, 2]. In the last quarter of a century, many scientists have studied interfacial phenomena between these biological systems and surfaces of artificial materials in order to design functional biomaterials for medical uses. Throughout these researches, it has been well recognized that biological responses to these surfaces include complicated acute and chronic reactions, eventually leading to cellular and tissue rejection in living bodies. In order to solve these problems, one must understand and appreciate any differences with respect to the structures and their functions between natural tissues and artificial materials. From this point of view, it should be stated that one of the dominant differences would be the mobility of molecules constructing these materials, and a quite new approach is urgently required to design biomaterials which can perform new functions in future advancing medicines.With this in mind, we initiated a study of cyclodextrin (CD)-based polyrotaxanes as novel biomaterials, because CD molecules would be expected to move along the polymeric chain. One of the characteristics seen in polyrotaxanes is the mobility of cyclic compounds, and they can be freely rotational and sliding if any intermolecular forces with the linear chain and the neighboring cyclic compound are eliminated (Figure 9.1). In particular, polyrotaxanes consisting of a-CD molecules and a poly (ethylene glycol) (PEG) [3, 4] chain are possible biomaterials in the structural components, as a-CD and PEG have been approved by the FDA for use in foods and drugs. We have prepared biological ligand-conjugated polyrotaxanes and Supramolecular Polymer Chemistry, First Edition. Edited by Akira Harada.

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Providing Natural Water Structure Surrounding Highly Mobile Maltose Groups Conjugated with Polyrotaxanes

Cited by 8 publications

References 14 publications

One-Pot Synthesis of Native and Permethylated α-Cyclodextrin-Containing Polyrotaxanes in Water

One-Pot Synthesis of Native and Permethylated α-Cyclodextrin-Containing Polyrotaxanes in Water

Molecular Switches and Machines with Mechanical Bonds

Emerging Biomedical Functions through ‘Mobile’ Polyrotaxanes

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