Browse
Submit Data
Databases
API
Help

Dataset Information

19 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A new class of fluorescent boronic acids that have extraordinarily high affinities for diols in aqueous solution at physiological pH.

ABSTRACT: The boronic acid group is an important recognition moiety for sensor design. Herein, we report a series of isoquinolinylboronic acids that have extraordinarily high affinities for diol-containing compounds at physiological pH. In addition, 5- and 8-isoquinolinylboronic acids also showed fairly high binding affinities towards D-glucose (K(a)=42 and 46 M(-1), respectively). For the first time, weak but encouraging binding of cis-cyclohexanediol was found for these boronic acids. Such binding was coupled with significant fluorescence changes. Furthermore, 4- and 6-isoquinolinylboronic acids also showed the ability to complex methyl ?-D-glucopyranose (K(a)=3 and 2 M(-1), respectively).

SUBMITTER: Cheng Y

PROVIDER: S-EPMC3545481 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

A new class of fluorescent boronic acids that have extraordinarily high affinities for diols in aqueous solution at physiological pH.

Cheng Yunfeng Y Ni Nanting N Yang Wenqian W Wang Binghe B

Chemistry (Weinheim an der Bergstrasse, Germany) 20101201 45

The boronic acid group is an important recognition moiety for sensor design. Herein, we report a series of isoquinolinylboronic acids that have extraordinarily high affinities for diol-containing compounds at physiological pH. In addition, 5- and 8-isoquinolinylboronic acids also showed fairly high binding affinities towards D-glucose (K(a)=42 and 46 M(-1), respectively). For the first time, weak but encouraging binding of cis-cyclohexanediol was found for these boronic acids. Such binding was c ...[more]

PMID: 20938931

Similar Datasets

Probing the general time scale question of boronic acid binding with sugars in aqueous solution at physiological pH.

Project description:The boronic acid group is widely used in chemosensor design due to its ability to reversibly bind diol-containing compounds. The thermodynamic properties of the boronic acid-diol binding process have been investigated extensively. However, there are few studies of the kinetic properties of such binding processes. In this report, stopped-flow method was used for the first time to study the kinetic properties of the binding between three model arylboronic acids, 4-, 5-, and 8-isoquinolinylboronic acids, and various sugars. With all the boronic acid-diol pairs examined, reactions were complete within seconds. The k(on) values with various sugars follow the order of D-fructose>D-tagatose>D-mannose>D-glucose. This trend tracks the thermodynamic binding affinities for these sugars and demonstrates that the 'on' rate is the key factor determining the binding constant.

| S-EPMC3355949 | biostudies-literature

Glutathione complex formation with mercury(II) in aqueous solution at physiological pH.

Project description:The mercury(II) complexes formed in neutral aqueous solution with glutathione (GSH, here denoted AH(3) in its triprotonated form) were studied using Hg L(III)-edge extended X-ray absorption fine structure (EXAFS) and (199)Hg NMR spectroscopy, complemented with electrospray ionization mass spectrometric (ESI-MS) analyses. The [Hg(AH)(2)](2-) complex, with the Hg-S bond distances at 2.325 ± 0.01 Å in linear S-Hg-S coordination, and the (199)Hg NMR chemical shift at -984 ppm, dominates except at high excess of glutathione. In a series of solutions with C(Hg(II)) ?17 mM and GSH/Hg(II) mole ratios rising from 2.4 to 11.8, the gradually increasing mean Hg-S bond distance corresponds to an increasing amount of the [Hg(AH)(3)](4-) complex. ESI-MS peaks appear at -m/z values of 1208 and 1230 corresponding to the [Na(4)Hg(AH)(2)(A)](-) and [Na(5)Hg(AH)(A)(2)](-) species, respectively. In another series of solutions at pH 7.0 with C(Hg(II)) ?50 mM and GSH/Hg(II) ratios from 2.0 to 10.0, the Hg L(III)-edge EXAFS and (199)Hg NMR spectra show that at high excess of glutathione (?0.35 M) about ?70% of the total mercury(II) concentration is present as the [Hg(AH)(3)](4-) complex, with the average Hg-S bond distance 2.42 ± 0.02 Å in trigonal HgS(3) coordination. The proportions of HgS(n) species, n = 2, 3, and 4, quantified by fitting linear combinations of model EXAFS oscillations to the experimental EXAFS data in our present and previous studies were used to obtain stability constants for the [Hg(AH)(3)](4-) complex and also for the [Hg(A)(4)](10-) complex that is present at high pH. For Hg(II) in low concentration at physiological conditions (pH 7.4, C(GSH) = 2.2 mM), the relative amounts of the HgS(2) species [Hg(AH)(2)](2-), [Hg(AH)(A)](3-), and the HgS(3) complex [Hg(AH)(3)](4-) were calculated to be 95:2:3. Our results are not consistent with the formation of dimeric Hg(II)-GSH complexes proposed in a recent EXAFS study.

| S-EPMC3059209 | biostudies-literature

A Phenanthroline-Based Fluorescent Probe for Highly Selective Detection of Extreme Alkalinity (pH?>?14) in Aqueous Solution.

Project description:Although numerous fluorescent probes are designed to detect the pH value in the past decades, developing fluorescent probes for extreme alkalinity (pH?>?14) detection in aqueous solution is still a great challenge. In this work, we utilized 1H-imidazo[4,5-f][1, 10] phenanthroline (IP) group as the recognition group of hydroxyl ion and introduced two triethylene glycol monomethyl ether groups to improve its solubility. This IP derivative, BMIP, possessed good solubility (25?mg/mL) in water. It displayed high selectivity toward extreme alkalinity (pH?>?14) over other ions and pH (from extreme acidity to pH?=?14). From 3 to 6?mol/L OH-, the exact concentration of OH- could be revealed by BMIP and the whole detection process just needed a short time (??10?s). Meanwhile, it exhibited good anti-interference ability and repeatability during the detection process. Through optical spectra and NMR analysis, its detection mechanism was proved to be deprotonation by hydroxyl ion and then aggregation-induced enhanced emission. Our study presents a new basic group based on which researchers can develop new fluorescent probes that can detect extreme alkalinity (pH?>?14) in aqueous solution.

| S-EPMC6751243 | biostudies-literature

Synthesis of a New Amino-Furopyridine-Based Compound as a Novel Fluorescent pH Sensor in Aqueous Solution.

Project description:Development of new fluorescent molecules, especially pH-sensitive fluorescent dyes, is always in high demand due to their wide applications in various fields and the limited number of common chromophores. In this work, a family of 3-amino-N-phenylfuro[2,3-b]pyridine-2-carboxamides (AFP) was synthesized as novel fluorescent compounds. Besides fluorescence in an organic solvent, AFP 1 and AFP 2 exhibit good fluorescence properties in both acidic and basic aqueous solution, which could be explained by protonation or different conformations formed in solution. Density functional theory (DFT) calculations on the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) of various conformations were performed for further support.

| S-EPMC7905818 | biostudies-literature

Functional Phenylboronate Polymers for the Recovery of Diols, Sugar Alcohols, and Saccharides from Aqueous Solution.

Project description:The ongoing transition from fossil to renewable feedstocks demands new efficient processes for an economically viable production of biomass-derived commodities and fine chemicals. Novel energy- and material-efficient product purification and separation will play a crucial role due to altered product and feed composition. The present study comprises the synthesis and tests of cross-linked p-vinylphenylboronate polymers for the separation of 18 diols, sugar alcohols, and saccharides, which can be obtained during biomass processing. The separation was based on molecular recognition, that is, esterification of the phenylboronate with vicinal diols. A correlation of the molecular complexation constant, the polymer swelling, and the maximum adsorption capacity was found. The adsorption curves over time were recorded. Preliminary results on competitive adsorption of binary mixtures showed a high potential for the separation of substrates with significantly different complexation constants. Desorption tests implied easier desorption of substrates that only adsorb on the outer polymer shell.

| S-EPMC9291334 | biostudies-literature

PH-Dependent Enantioselectivity of D-amino Acid Oxidase in Aqueous Solution.

Project description:D-amino acid oxidases (DAAO) are stereospecific enzymes which are generally almost inactive towards L-enantiomer in neutral solution when L-, D-amino acids are supplied as substrates. In this paper, the D-amino acid oxidase can catalytic oxidize L-amino acids by modulating pH of aqueous solution. With L-Pro as substrate, the catalytic rate (k cat) and the affinity (K m) of DAAO were 6.71?s-1 and 33?mM at pH 8.0, respectively, suggesting that optimal pH condition enhanced the activity of DAAO towards L-Pro. Similar results were obtained when L-Ala (pH 9.8), L-Arg (pH 6.5), L-Phe (pH 9.0), L-Thr (pH 9.4), and L-Val (pH 8.5) were catalyzed by DAAO at various pH values. The racemization of the L-amino acids was not found by capillary electrophoresis analysis during oxidation, and quantification analysis of L-amino acids before and after catalytic reaction was performed, which confirmed that the modulation of enantioselectivity of DAAO resulted from the oxidation of L-amino acids rather than D-amino acids by changing pH. A mechanistic model was proposed to explain enhanced activity of DAAO towards L-amino acids under optimal pH condition.

| S-EPMC5462808 | biostudies-literature

Selective Sugar Recognition by Anthracene-Type Boronic Acid Fluorophore/Cyclodextrin Supramolecular Complex Under Physiological pH Condition.

Project description:We synthesized novel PET (photoinduced electron transfer)-type fluorescence glucose probe 1 [(4-(anthracen-2-yl-carbamoyl)-3-fluorophenyl)boronic acid], which has a phenylboronic acid (PBA) moiety as the recognition site and anthracene as the fluorescent part. Although the PBA derivatives dissociate and bind with sugar in the basic condition, our new fluorescent probe can recognize sugars in the physiological pH by introducing an electron-withdrawing fluorine group into the PBA moiety. As a result, the pK a value of this fluorescent probe was lowered and the probe was able to recognize sugars at the physiological pH of 7.4. The sensor was found to produce two types of fluorescent signals, monomer fluorescence and dimer fluorescence, by forming a supramolecular 2:1 complex of 1 with glucose inside a ?-cyclodextrin (?-CyD) cavity. Selective ratiometric sensing of glucose by the 1/?-CyD complex was achieved in water at physiological pH.

| S-EPMC6890849 | biostudies-literature

Synthesis and pH-responsive dissociation of framboidal ABC triblock copolymer vesicles in aqueous solution.

Project description:A series of pH-responsive all-methacrylic ABC triblock copolymer vesicles were prepared from precursor diblock copolymer vesicles via RAFT seeded emulsion polymerisation. Microphase separation between the two hydrophobic membrane-forming B and C blocks produced a distinctive framboidal morphology, for which the mean globule size can be tuned by adjusting the triblock copolymer composition. These vesicles remain intact at neutral pH, but undergo irreversible dissociation on addition of acid as a result of protonation of the tertiary amine groups located within the third block. Small-angle X-ray scattering (SAXS) was utilised to characterise the morphologies formed at pH 8 and pH 3. According to time-resolved SAXS studies, the acid-induced dissociation of these pH-responsive framboidal vesicles involves appreciable membrane swelling within 50 ms and is complete.

| S-EPMC5885938 | biostudies-literature

4-Fluoro-Threonine: From Diastereoselective Synthesis to pH-Dependent Conformational Equilibrium in Aqueous Solution.

Project description:4-Fluoro-threonine, the only fluoro amino acid of natural origin discovered so far, is an interesting target for both synthetic and theoretical investigations. In this work, we lay the foundation for spectroscopic characterization of 4-fluoro-threonine. First, we report a diastereoselective synthetic route, which is suitable to produce synthetic material for experimental characterization. The addition of the commercially available ethyl isocyanoacetate to benzyloxyacetaldehyde led to the corresponding benzyloxy-oxazoline, which was hydrolyzed and transformed into ethyl (4S*,5S*)-5-hydroxymethyl-2-oxo-4-oxazolidinecarboxylate in a few steps. Fluorination with diethylamino sulfur trifluoride (DAST) afforded ethyl (4S*,5S*)-5-fluoromethyl-2-oxo-4-oxazolidinecarboxylate, which was deprotected to give the desired diastereomerically pure 4-fluoro-threonine, in 8-10% overall yield. With the synthetic material in our hands, acid-base titrations have been carried out to determine acid dissociation constants and the isoelectric point, which is the testing ground for the theoretical analysis. We have used machine learning coupled with quantum chemistry at the state-of-the-art to analyze the conformational space of 4-fluoro-threonine, with the aim of gaining insights from the comparison of computational and experimental results. Indeed, we have demonstrated that our approach, which couples a last-generation double-hybrid density functional including empirical dispersion contributions with a model combining explicit first-shell molecules and a polarizable continuum for describing solvent effects, provides results and trends in remarkable agreement with experiments. Finally, the conformational analysis applied to fluoro amino acids represents an interesting study for the effect of fluorine on the stability and population of conformers.

| S-EPMC8158790 | biostudies-literature

Upper Critical Solution Temperature Behavior of pH-Responsive Amphoteric Statistical Copolymers in Aqueous Solutions.

Project description:Amphoteric statistical equivalent copolymers (P(2VP/NaSS) n ) composed of 2-vinylpyridine (2VP) and anionic sodium p-styrenesulfonate (NaSS) were prepared via reversible addition-fragmentation chain transfer polymerization. The degrees of polymerization (n) were 19 and 95. The monomer reactivity ratio, time conversion profile, and 1H nuclear magnetic resonance diffusion-ordered spectra suggested that the copolymerization of 2VP and NaSS provided statistical or near to random copolymers. P(2VP/NaSS) n exhibited an upper critical solution temperature (UCST) in acidic aqueous solutions on the basis of the charge interactions between the protonated cationic 2VP and anionic NaSS units. With an increase in pH value, the interaction was weakened because of the deprotonation of the 2VP units, thus reducing the UCST. At high [NaCl], the electrostatic interactions among the polymers were weakened because of the screening effect, and again, the UCST was reduced. With an increase in polymer concentration, the intra- and interpolymer interactions increased because of some entanglement, and the UCST consequently increased. Electrostatic interactions among the polymer chains with high molecular weight occurred easier than those among the low-molecular-weight polymer chains, which increased the UCST. The UCST also increased when deuterium oxide was used instead of hydrogen oxide, which was due to the isotopic effect. Hence, the UCST of P(2VP/NaSS) n can be adjusted according to the desired application.

| S-EPMC8028163 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data