A polyrotaxane gel using boronic acid-appended γ-cyclodextrin as a hybrid cross-linker

Wisdom from nature: Plant-derived polyphenolic compounds can crosslink boronic acid functionalized polymers through formation of dynamic covalent bonds and function as both cross-linker and bioactive cargo.

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Self-assembly and disassembly of stimuli responsive tadpole-like single chain nanoparticles using a switchable hydrophilic/hydrophobic boronic acid cross-linker

Polymer Chemistry ◽

10.1039/c7py00828g ◽

2017 ◽

Vol 8 (28) ◽

pp. 4079-4087 ◽

Cited By ~ 23

Author(s):

Junliang Zhang ◽

Joji Tanaka ◽

Pratik Gurnani ◽

Paul Wilson ◽

Matthias Hartlieb ◽

...

Keyword(s):

Self Assembly ◽

Boronic Acid ◽

Stimuli Responsive ◽

Single Chain ◽

Cross Linker

pH/sugar responsive behaviour of tadpole-like single chain nanoparticles based on a switchable hydrophilic/hydrophobic boronic acid cross-linker is described.

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Bagworm Survival and Feeding Preferences as Indicators of Resistance among Maples

Journal of Environmental Horticulture ◽

10.24266/0738-2898-20.3.138 ◽

2002 ◽

Vol 20 (3) ◽

pp. 138-142

Author(s):

William E. Klingeman

Keyword(s):

Host Plant ◽

Ornamental Plants ◽

Larval Feeding ◽

Eastern United States ◽

Feeding Preferences ◽

Survival And Development ◽

Early Instar ◽

Moderate Resistance ◽

Hybrid Cross ◽

Plant Susceptibility

Abstract The bagworm (Thyridopteryx ephemeraeformis (Haworth)) is a polyphagous, native pest of numerous deciduous and evergreen ornamental plants. Bagworm larvae were used to investigate host plant susceptibility among ten species and cultivars of maples that are economically important and commonly encountered in landscapes in the eastern United States. Data analyses from 48-hour choice assays, conducted in the laboratory during 2000 and 2001, indicated that differences existed among maples for bagworm feeding preferences and host plant susceptibility. Results from the 48-hour trials were not as accurate as seasonal no-choice assays, however. No-choice assays during both seasons quantified resistance among maples that limited larval bagworm survival and development. Measurements of larval feeding injury demonstrated resistance in paperbark maple (Acer griseum (Franch.) Pax) and trident maple (A. buergerianum Miq.) when compared with other maples. Laboratory results were corroborated during 2001 by a no-choice field assay, in which early instar bagworm larvae performed well on the majority of maples. In contrast, paperbark maple and trident maple were resistant to bagworm feeding, while ‘Autumn Blaze’ Freeman maple (A. x freemanii E. Murray), a hybrid cross obtained by breeding A. rubrum with A. saccharinum, showed moderate resistance.

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A Boronic Acid-Based Fluorescence Hydrogel for Monosaccharide Detection

10.26434/chemrxiv.7176989 ◽

2018 ◽

Author(s):

Suying Xu ◽

Adam Sedgwick ◽

Souad Elfecky ◽

Wenbo Chen ◽

Ashley Jones ◽

...

Keyword(s):

Fluorescent Probe ◽

Boronic Acid ◽

Binding Constants ◽

Strong Fluorescence ◽

Fluorescence Response ◽

Turn On ◽

Fluorescence Turn On ◽

Hydrogel System

A boronic acid-based anthracene fluorescent probe was functionalised with an acrylamide unit to incorporate into a hydrogel system for monosaccharide detection. In solution, the fluorescent probe displayed a strong fluorescence turn-on response upon exposure to fructose, and an expected trend in apparent binding constants, as judged by a fluorescence response where D-fructose > D-galactose > D-mannose > D-glucose. The hydrogel incorporating the boronic acid monomer demonstrated the ability to detect monosaccharides by fluorescence with the same overall trend as the monomer in solution with the addition of fructose resulting in a 10-fold enhancement (≤ 0.25 M).

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Theoretical Studies of the Acid-Base Equilibria in a Model Active Site of the Human 20S Proteasome

10.26434/chemrxiv.13388753.v1 ◽

2020 ◽

Author(s):

Jon Uranga ◽

Lukas Hasecke ◽

Jonny Proppe ◽

Jan Fingerhut ◽

Ricardo A. Mata

Keyword(s):

Active Site ◽

Boronic Acid ◽

Computational Study ◽

Ubiquitin Proteasome System ◽

Bayesian Optimization ◽

Inhibition Mechanism ◽

20S Proteasome ◽

Acid Base ◽

Ubiquitin Proteasome ◽

Infection Cycles

The 20S Proteasome is a macromolecule responsible for the chemical step in the ubiquitin-proteasome system of degrading unnecessary and unused proteins of the cell. It plays a central role both in the rapid growth of cancer cells as well as in viral infection cycles. Herein, we present a computational study of the acid-base equilibria in an active site of the human proteasome, an aspect which is often neglected despite the crucial role protons play in the catalysis. As example substrates, we take the inhibition by epoxy and boronic acid containing warheads. We have combined cluster quantum mechanical calculations, replica exchange molecular dynamics and Bayesian optimization of non-bonded potential terms in the inhibitors. In relation to the latter, we propose an easily scalable approach to the reevaluation of non-bonded potentials making use of QM/MM dynamics information. Our results show that coupled acid-base equilibria need to be considered when modeling the inhibition mechanism. The coupling between a neighboring lysine and the reacting threonine is not affected by the presence of the inhibitor.

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Arylboronic Acids in Self-condensation of Glucosamines Forming Deoxyfructosazine, Catalysts or Reagents?

10.26434/chemrxiv.7528376 ◽

2019 ◽

Author(s):

Meifeng Wang ◽

Gan Zhu ◽

Yiqun Li ◽

Liuqun Gu

Keyword(s):

Molecular Recognition ◽

Boric Acid ◽

Boronic Acid ◽

Catalytic Mechanism ◽

Organic Transformations ◽

Food Industries ◽

Arylboronic Acids ◽

Excess Amount ◽

Phenyl Boronic Acid ◽

Boron Acid

Arylboronic acids were widely used as efficient catalysts in direct amide formation and other organic transformations. Surprisingly, reports on their use as catalysts in carbohydrates synthesis are very rare even though boron acid-diol complexation was extensively investigated in molecular recognition for saccharides and so on. Here we developed an efficient arylboronic acids catalyzed dimerization of glucosamines forming deoxyfructosazine which is important compound in pharmaceutical and food industries, against a commonly held belief that excess amount of phenyl boronic acid (or boric acid) is a must. A catalytic mechanism was also proposed and arylboronic acids instead of their boronates was identified as catalysts.

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