820-11-1Relevant articles and documents
Oxidase-mimicking activity of ultrathin MnO2 nanosheets in a colorimetric assay of chlorothalonil in food samples
Dai, Zhihui,Li, Zhenxi,Lu, Yuxiao,Sheng, Enze,Tan, Yuting,Xiao, Yue
, (2020/07/02)
Chlorothalonil is a class of 2B carcinogen which is widely used in the prevention and treatment of fungal diseases in food samples. Its residual problem has been increasingly concerned by society. In this paper, a fast and simple colorimetric assay based on Manganese dioxide nanosheets (MnO2 NSs)-oxidize 3,3′,5,5′-tetramethylbenzidine (TMB) platform was used to detect residual pesticide chlorothalonil in food samples. Under optimal conditions, the half maximal inhibitory concentration and the limit of detection of chlorothalonil were 3.27 and 0.024 ng/mL. There were no obvious cross-reactivity between chlorothalonil and interference substances. The recoveries shown the satisfactory results. The results of colorimetric assay for the authentic samples were largely consistent with gas chromatography. Therefore, the proposed method would be convenient and satisfactory analytical methods for the monitoring of chlorothalonil. Furthermore, the MnO2 – TMB system was used to produce test strips for quick and convenient visual detection of chlorothalonil with good performance.
A fluorescent probe for estimation of adenosine diphosphate and monitoring of glucose metabolism
Kumar, Arun,Prasher, Parteek,Singh, Palwinder
, p. 3071 - 3079 (2014/05/06)
An ADP selective fluorescent probe working in aqueous medium was identified and the change in fluorescence as a function of ADP concentration was standardized. Using this probe, all the steps of glycolysis coupled with ATP/ADP inter-conversion and oxidative breakdown of pyruvate in the mitochondria were monitored and the consumption/production of ATP/ADP at each step was quantified. The quantity of ADP present in the mitochondria, taken from different body parts of a pig, was also determined. It is hypothesized that an appropriate modification of the technique may provide a diagnostic tool for monitoring biochemical pathways as well as for quick estimation of ADP in the mitochondria and other cell organelles.
Broad specificity of human phosphoglycerate kinase for antiviral nucleoside analogs
Gallois-Montbrun, Sarah,Faraj, Abdesslem,Seclaman, Edward,Sommadossi, Jean-Pierre,Deville-Bonne, Dominique,Véron, Michel
, p. 1749 - 1756 (2007/10/03)
Nucleoside analogs used in antiviral therapies need to be phosphorylated to their tri-phospho counterparts in order to be active on their cellular target. Human phosphoglycerate kinase (hPGK) was recently reported to participate in the last step of phosphorylation of cytidine l-nucleotide derivatives [Krishnan PGE, Lam W, Dutschman GE, Grill SP, Cheng YC. Novel role of 3-phosphoglycerate kinase, a glycolytic enzyme, in the activation of l-nucleoside analogs, a new class of anticancer and antiviral agents. J Biol Chem 2003;278:36726-32]. In the present work, we extended the enzymatic study of human PGK specificity to purine and pyrimidine nucleotide derivatives in both d- and l-configuration. Human PGK demonstrated catalytic efficiencies in the 104-10 5 M-1 s-1 range for purine ribo-, deoxyribo- and dideoxyribonucleotide derivatives, either in d- or l-configuration. In contrast, it was poorly active with natural pyrimidine d-nucleotides (less than 103 M-1 s-1). Pyrimidine l-enantiomers, which are promising therapeutic analogs against B hepatitis, were 2-25 times better substrates than their d-counterparts. The broad specificity of substrate of human PGK suggests that this enzyme may be involved in the cellular activation of several antiviral nucleoside analogs including dideoxyinosine, acyclovir, l-2′-deoxycytosine and l-2′-deoxythymidine.
Reactivity of some sugars and sugar phosphates towards gold(III) in sodium acetate-acetic acid buffer medium
Sen Gupta, Kalyan Kali,Pal, Biswajit,Begum, Bilkis Ara
, p. 115 - 123 (2007/10/03)
The kinetics of the oxidation of some aldoses and aldose phosphates have been studied spectrophotometrically in sodium acetate-acetic acid buffer medium at different temperatures. The reactions are first order with respect to [Au(III)] and [substrate]. Both H+ and Cl- ions retard the reaction. The reactions appear to involve different gold(III) species, viz. AuCl4/-, AuCl3(OH2) and AuCl3(OH)-. The results are interpreted in terms of the probable intermediate formation of free radicals and Au(II). Aldoses react with gold(III) in the order: triose > tetrose > pentose > hexose. The sugar phosphates react with gold(III) at a faster rate than the parent sugars except glucose-1-phosphate, which reacts at slower rates than glucose. A tentative reaction mechanism leading to the formation of products has been suggested.
The synthesis of novel bisphosphonates as inhibitors of phosphoglycerate kinase (3-PGK)
Caplan, Neil A.,Pogson, Christopher I.,Hayes, David J.,Blackburn, G. Michael
, p. 421 - 437 (2007/10/03)
A series of conformationally-restrained analogues of 1,3-bisphospho-D-glyceric acid (1,3-BPG) 1 has been synthesised for use as inhibitors of 3-PGK (E.C. 2.7.2.3). These compounds have non-scissile phosphonate linkages and also incorporate α-halogen substituents to make them isopolar and isosteric mimics of the natural substrate. A monocyclic aryl core between the two phosphoryl centres provides both a rigid framework linking these moieties and loci for further substitution. The compounds were tested against human 3-PGK and found to be good competitive inhibitors. α-Fluorination of the phosphonic acids increased the affinity for the enzyme into the submicromolar range. Correlation of IC50 data with pKa. and pKa, values indicates that the acidity of the phosphoryl group exerts a strong influence on protein binding. The Royal Society of Chemistry 2000.
Reactivities of some sugar phosphates towards permanganate in perchloric acid medium and mechanism of the oxidation processes
Sen Gupta, Kalyan Kali,Tribedi, Partha Sarathi,Sen Gupta, Shipra
, p. 427 - 430 (2007/10/03)
The reactivities of some sugar phosphates towards permanganate have been examined in perchloric acid medium. The reactions are first order in [sugar phosphate] and [MnO4-]. The rate increases with increase in [H+]. The reactivities follow the order: erythrose 4-phosphate> ribose 5-phosphate> fructose 1,6-diphosphate> glucose 6-phosphate> glucose 1-phosphate. The mechanism of the reactions is discussed.
Chemistry of α-Aminonitriles. Formation of 2-Oxoethyl Phosphates ('Glycolaldehyde Phosphates') from rac-Oxiranecarbonitrile and on (Formal) Constitutional Relationships between 2-Oxoethyl Phosphates and Oligo(hexo- and pentopyranosyl)nucleotide Backbones
Pitsch, Stefan,Pombo-Villar, Esteban,Eschenmoser, Albert
, p. 2251 - 2285 (2007/10/02)
Oxiranecarbonitrile in basic aqueous solution at room temperature reacts regioselectively with inorganic phosphate to give the cyanohydrin of 2-oxoethyl phosphate ('glycolaldehyde phosphate'), a source of (the hydrate of) the free aldehyde, preferably in the presence of formaldehyde.In aqueous phosphate solution buffered to nearly neutral pH, oxiranecarbonitrile produces the phosphodiester of glycolaldehyde as its bis-cyanohydrin in good yield.In contrast to mono- and dialkylation, trialkylation of phosphate with oxiranecarbonitrile is difficult, and the triester derivative is highly sensitive to hydrolysis.Glycolaldehyde phosphate per se is of prebiotic interest, since it had been shown to aldomerize in basic aqueous solution regioselectively to rac-hexose 2,4,6-triphosphates and- in the presence of formaldehyde - mainly to rac-pentose 2,4-diphosphates with, under appropriate conditions, rac-ribose 2,4-diphosphate as the major reaction product.However, the question as to whether oxiranecarbonitrile itself has the potential of having been a prebiological natural constituent remains unanswered.Backbone structures of hexopyranosyl-oligonucleotides with phosphodiester linkages specifically between the positions 6'->4',6'->2', or 4'->2' of the sugar residues can formally be derived via the (hypothetical) aldomerization pathway, a combinatorial intermolecular aldomerization of glycolaldehyde phosphate and bis(glycolaldehyde)phosphodiester in a 1:1 ratio.The constitutional relationships revealed by this synthetic analysis has played a decisive role as a selection criterion in the pursuit of our experimental studies toward a chemical etiology of the natural nucleic acids' structure.The Discussion in this paper delineates how the analysis contributed to the conception of the structure of p-RNA.The English Footnotes to Schemes 1-11 provi de an extension of this summary.
