- A Highly Selective and Sensitive Colorimetric Chemosensor for the Detection of Hydrogen Sulfide: A Real-time Application in Multiple platforms
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Calorimetric chemosensors are found to be advantageous sensing systems due to their simplicity and favorable responsive properties. Although some colorimetric probes have been reported to detect hydrogen sulfide (H2S), the creation of rapid, highly selective and sensitive probes for the detection of H2S remains a challenging target. In this work, we established dinitrosulphonamide decorated phenanthridine and 2,4-dinitro-N-(4-(7,8,13,14-tetrahydrodibenzo[a, i]phenanthridin-5-yl)phenyl)benzenesulfonamide (PHSH), for the calorimetric detection of H2S. H2S-triggered thiolysis of PHSH resulted in a marked absorption enhancement alongside a visual color change from colorless to dark yellow. The result indicated that the chemosensor showed high sensitivity and selectivity with a fast response of less than 10?s with a detection limit as low as 6.5?nM. The chemosensor reaction mechanism with H2S was studied by UV-vis, 1H NMR, mass and HPLC analysis. In addition, the chemosensor has been used for the determination of H2S in many real-time samples.
- Jothi, Dhanapal,Munusamy, Sathishkumar,Kulathu Iyer, Sathiyanarayanan
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- A new near-infrared fluorescent chemodosimeter for discrimination of sulfide from disulfide
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A new near-infrared fluorescent “turn-on” chemodosimeter (probe 1) based on dicyanomethylene-4H-chromene fluorophore for sulfide was developed. Probe 1 showed good fluorescence selectivity to sulfide over other anions and thiol-containing compounds. The d
- Xie, Puhui,Zhu, Yanru,Huang, Xuewei,Gao, Guangqin,Guo, Fengqi,Yang, Guoyu
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- A 2,5-diaryl-1,3,4-oxadiazole-based fluorescent probe for rapid and highly selective recognition of hydrogen sulfide with a large Stokes shift through switching on ESIPT
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A new 2,5-diaryl-1,3,4-oxadiazole derived ratiometric fluorescent probe (OXDNP) for hydrogen sulfide recognition has been developed. Probe OXDNP displays highly selective and sensitive detection to HS? over other anions and thiol-containing amino acids in DMSO solution with fast response and a large Stokes shift. Through HS? induced thiolysis of the dinitrophenyl ether, the excited state intramolecular proton transfer (ESIPT) featured precursor was released, which led to dual fluorescence emission ‘turn on’ and ratiometric emission behavior of the sensing system. The pseudo-first-order reaction rate constant was calculated to be 1.234 s?1. The HS? recognition mechanism was proved by HPLC–MS and 1H NMR comparison investigations.
- Tang, Lijun,Zheng, Zhuxuan,Zhong, Keli,Bian, Yanjiang
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- Dual-functional multi-application probe: Rapid detection of H2S and colorimetric recognition of HSO3? in food and cell
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Since hydrogen sulfide (H2S) and bisulfite (HSO3?) are widely used in the biological environment and industrial production, many fluorescent probes have been developed to detect them individually. However, designing and sy
- Chen, Lin,Hou, Shuhua,Li, Xuepeng,Tang, Lijun,Tang, Yiwei,Yan, Xiaomei,Zhong, Keli
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- A fluorescence turn-on probe for hydrogen sulfide and biothiols based on PET & TICT and its imaging in HeLa cells
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In this paper, a photoinduced electron transfer (PET)& twisted intramolecular charge transfer (TICT)-based fluorescent probe (1) for detecting biothiols (GSH/Cys/Hcy) and hydrogen sulfide with fluorescence turn on was developed. The probe could recognize
- Jin, Xiaodong,Zhang, Caiting,Zhang, Xueqiong,Zhong, Hui,Zhu, Hongjun
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supporting information
(2020/09/02)
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- A PET-based turn-on fluorescent probe for sensitive detection of thiols and H2S and its bioimaging application in living cells, tissues and zebrafish
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A turn-on fluorescent probe, containing a naphthalimide platform and benzothiazole modified by the 2,4-dinitrobenzenesulfonyl (DNBS) group, was designed as an efficient fluorescent probe for sensitive detection of biological thiols and H2S spec
- Xu, Kaixin,He, Longwei,Yang, Yunzhen,Lin, Weiying
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supporting information
p. 2865 - 2869
(2019/02/17)
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- Fluorogenic protein labeling through photoinduced electron transfer-based BL-tag technology
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Keeping quenchers on a short leash: Shortening of the linker chain length combined with modification of the quencher moiety was found to improve fluorogenic probes useful for protein labeling by the mutant β-lactamase-tag (BL-tag) technology. The most eff
- Sadhu, Kalyan K.,Mizukami, Shin,Lanam, Carolyn R.,Kikuchi, Kazuya
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supporting information; scheme or table
p. 272 - 276
(2012/05/20)
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- Selective reduction of nitroaromatic compounds on silver nanoparticles by visible light
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For the first time, we report experimentally and theoretically that nitroaromatic compounds, 2,4-dinitrobenzenethiol and 4-chloro-2- nitrobenzenethiol, on silver sols can be selectively reduced to 2-amino-4-nitrobenzenethiol and 2-amino-4-chlorobenzenethiol simply by irradiating with a visible light in ambient conditions, and the selective photoreduction is a very facile process. The results of quantum chemical calculations are in good agreement with our experimental data. Copyright
- Xia, Lixin,Hu, Xinhu,Sun, Mengtao,Li, Jushi,Yang, Donghui,Wang, Xiaofang,Xu, Hongxing
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p. 1024 - 1028
(2012/10/29)
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- Kinetics and mechanism of the reactions of S-2,4-dinitrophenyl 4-substituted thiobenzoates with secondary alicyclic amines
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The title reactions, in 44 wt % ethanol-water at 25.0 °C, exhibit slightly curved Bronsted-type plots (log kN versus pK a of amines) with slopes β1 = 0.1-0.44 (at high pKa) and β2 ca. 0.7 (at low pKa). The magnitude of some of these slopes, together with the fact that the curvature center (pKa0 = 9.5-10.8) does not change with the electronic effects of the benzoyl substituent, suggests that these reactions are not stepwise, but concerted.
- Castro, Enrique A.,Aguayo, Raul,Bessolo, Jorge,Santos, Jose G.
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p. 7788 - 7791
(2007/10/03)
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- Kinetics and Mechanism of the Benzenethiolysis of O-Ethyl S-(2,4-Dinitrophenyl) and O-Ethyl S-(2,4,6-Trinitrophenyl) Dithiocarbonates and O-Methyl O-(2,4-Dinitrophenyl) Thiocarbonate
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Reactions of O-ethyl 2,4-dinitrophenyl dithiocarbonate (EDNPDTC), O-ethyl 2,4,6-trinitrophenyl dithiocarbonate (ETNPDTC), and O-methyl O-(2,4-dinitrophenyl) thiocarbonate (MDNPTOC) with a series of benzenethiolate anions in aqueous solution, at 25.0 °C and an ionic strength of 0.2 M (KCl), are subjected to a kinetic investigation. Under excess benzenethiolate, these reactions obey pseudo-first-order kinetics and are first order in benzenethiolate. Nonetheless, similar reactant concentrations were used in the reactions of 4-nitrobenzenethiolate anion with the ethyl trinitrophenyl ester (ETNPDTC), which showed overall second-order kinetics. The nucleophilic rate constants (kN) are pH independent, except those for the reactions of ETNPDTC with the X-benzenethiolates with X = H, 4-Cl, and 3-Cl, which increase as pH decreases. The Bronsted-type plots (log kN vs pK a of benzenethiols) are linear with slopes β = 0.66 for the reactions of both ethyl dinitrophenyl ester (EDNPDTC) and ethyl trinitrophenyl ester (ETNPDTC) and β = 0.58 for those of the thiocarbonate ester (MDNPTOC). For the benzenethiolysis of MDNPTOC and EDNPDTC, no breaks were found in the Bronsted-type plots at pKa 4.1 and 3.4, respectively, consistent with concerted mechanisms. Benzenethiolysis of the ethyl trinitrophenyl ester (ETNPDTC) should also be concerted in view of the even more unstable tetrahedral intermediate that would have been formed had this reaction been stepwise. ETNPDTC is more reactive toward benzenethiolate anions than EDNPDTC due to the better leaving group involved in the former substrate. The kN values found for the reactions of EDNPDTC with benzenethiolates are larger than those obtained for the concerted reactions of the same substrate with isobasic phenoxide anions. This is explained by Pearson's hard and soft acids and bases principle. The concerted mechanism for the benzenethiolysis of MDNPTOC, in contrast to the stepwise mechanism found for the phenolysis of this substrate, is attributed to the greater kinetic instability of the hypothetical tetrahedral intermediate formed in the former reaction, due to the greater nucleofugality of ArS- compared with an isobasic ArO-. Benzenethiolates are more reactive toward MDNPTOC and EDNPDTC than the corresponding carbonate and thiolcarbonate, respectively. This is also in accordance with the HSAB principle, since benzenthiolates are relatively soft bases that prefer to bind to a relatively soft thiocarbonyl center rather than a relatively hard carbonyl center.
- Castro, Enrique A.,Pavez, Paulina,Santos, Jose G.
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p. 9034 - 9039
(2007/10/03)
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- Nucleophilic aromatic substitution for heteroatoms: An oxidative electrochemical approach
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The nucleophilic aromatic substitution for heteroatom through electrochemical oxidation of the intermediate σ-complexes (Meisenheimer complexes) in simple nitroaromatic compounds is reported for the first time (NASX process). The studies have been carried out with hydride, cyanide, fluoride, methoxy, and ethanethiolate anions and n-butylamine as a nucleophile, at the cyclic voltammetry (CV) and preparative electrolysis level. The cyclic voltammetry experiments allow for detection and characterization of the σ-complexes and they have led us to a proposal for the mechanism of the oxidation step. Furthermore, the power of the CV technique in the analysis of the reaction mixture throughout the whole chemical and electrochemical process is described.
- Gallardo, Iluminada,Guirado, Gonzalo,Marquet, Jordi
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p. 2548 - 2555
(2007/10/03)
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- Hydrolysis and aminolysis of alkyl xanthate esters and cellulose analogues
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The hydrolysis and aminolysis of a series of S-substituted O-alkylxanthate esters was studied in 20% v/v aqueous methanol at 35°C. The pH-rate profiles of the hydrolyses showed water and hydroxide-ion-catalyzed reactions. The reaction of 2,4-dinitrophenyl cellulose xanthate (CelXDNP) and p-nitrobenzyl cellulose xanthate (CelXNB) with polyalanine and lysozyme produced a covalent bond between the polypeptide and the cellulose matrix, as shown by solid-state 13C NMR. However, the nature of the bonding could not be identified. The reaction of nucleophiles (H2O, OH-, RNH2) and xanthic esters was consistent with an addition-elimination mechanism through a tetrahedral intermediate. Bronsted plots against the pKa of the nucleophile (βnu) or the nucleofuge of the substrate (βlg) were used to characterize the rate-determining step. The pKa values of the nucleophiles ranged between -1.74 and 15.74, and for the nucleofuges, they were in the range of 10.50-0.92. For nucleophiles with pKa values up to about 10, βlg was 0.10-0.15, and βnu changed from 0.48 to 0.35 for the strongest electron-withdrawing nucleofuge. It was concluded that the water-catalyzed hydrolyses, and also aminolyses with moderately basic amines, occur with rate-determining formation of the tetrahedral intermediate. For strong bases such as hydroxide ion, the disappearance of the intermediate becomes the slowest step. The reaction of cellulose xanthic esters with external nucleophiles as hydroxide ion and amines shows simple first-order kinetics and is slower than alkyl or sugar xanthates, probably due to the diffusion effect through the tight cybotactic region of cellulose.
- Humeres, Eduardo,Soldi, Valdir,Klug, Marilene,Nunes, Mauricea,Oliveira, Celia M.S.,Barrie, Patrick J.
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p. 1050 - 1056
(2007/10/03)
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- Structure - reactivity correlation in the reactions of pyrrolidine with O-ethyl S-aryl dithiocarbonates in aqueous ethanol
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The reactions of pyrrolidine with O-ethyl S-(X-phenyl) dithiocarbonates (X = 4-methyl, 4-methoxy, H, 4-chloro, 4-nitro, 2,4-dinitro, and 2,4,6-trinitro) are subjected to a kinetic study in 44 wt% aqueous ethanol, 25.0°C, and ionic strength 0.2 M (maintained with KCl). Pseudo-first-order kinetics are found under amine excess. Linear plots of the pseudo-first-order rate coefficient against concentration of free-base pyrrolidine are obtained for all the reactions, nucleophilic rate coefficient (kN) being the slope of such plots. The Bronsted-type plot (log kN vs. pKa for the leaving group) is linear with slope β1g = -0.2, which is consistent with a mechanism through a tetrahedral intermediate (T±) where its formation is rate determining. The β1g value is very similar to that found in the same reactions in water. There is a great difference in the mechanism of the reactions of O-ethyl S-phenyl dithiocarbonate with pyrrolidine (order one in amine) and piperidine (complex order in amine) in aqueous ethanol, and this is attributed to a greater nucleofugality from T± of piperidine rather than pyrrolidine.
- Castro,Cabrera,Santos
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p. 113 - 117
(2007/10/03)
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- Stepwise Mechanisms of the Aminolyses of 4-Nitrophenyl and 2,4-Dinitrophenyl O-Ethyl Dithiocarbonates in Aqueous Ethanol
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The reactions of the title substrates with a series of secondary alicyclic amines are subjected to a kinetic study in 44 wtpercent aqueous ethanol, at 25.0 deg C, ionic strength 0.2 M (maintained with KCl).Pseudo-first-order kinetics are found under amine excess.The order in amine obtained is one in the reactions of all amines.The Broensted-type plots for the overall second-order rate coefficients are biphasic with slopes β1 = 0.3 (high pKa), β2 = 0.95 (low pKa) for the aminolysis of the 4-nitro derivative, and β1 = 0.3 and β2 = 0.80 for the aminolysis of the dinitro compound; the pKa values at the curvature center are pK0a 9.8 and 9.5, respectively.From a comparison of these pK0a values with those found in the same reactions in water and the shapes of the Broensted-type plots, it is concluded that these reactions are stepwise, with the formation of a zwitterionic tetrahedral intermediate in the reaction pathway.
- Castro, Enrique A.,Munoz, Gabriel,Salas, Mirtha,Santos, Jose G.
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p. 987 - 996
(2007/10/02)
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- Structure-Reactivity Relationships in the Aminolysis of O-Ethyl S-Aryl Dithiocarbonates in Aqueous Solution
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The reactions of O-ethyl S-(X-phenyl) diothiocarbonates (X = p-Cl, p-Me, and p-MeO) with a series of secondary alicyclic amines and those of the same substrates and analogous derivatives (X = H, p-NO2, 2,4-(NO2)2 with pyrrolidine are subjected to a kinetic study in water, 25.0 deg C, ionic strength 0.2 M (KCl).The reactions of piperidine and pyrrolidine show second-order kinetics (first order in amine) with the formation of a zwitterionic tetrahedral intermediate (T+/-) as the rate-determining step.The reactions of the other amines exhibit orders in amine differentfrom one, compatible with the presence of an anionic intermediate (T-), resulting from a kinetically important proton transfer from T+/- to the amine.The rate of this proton transfer is faster than that of expulsion of arylthiolate from T+/- (k2) as evidenced by the estimation of these rate coefficients.The rate constants for formation of T+/- (k1) are obtained experimentally, and those for amine expulsion from T+/- (k-1) are estimated.Equations for k1 and k-1 are derived as functions of the basicity of the amine and leaving (aryl thiolate) groups.Comparison of the k-1 and k2 values found in the present reactions with those obtained in the aminolysis of aryl dithioacetates shows that substitution of Me by EtO as the "acyl" group of the zwitterionic tetrahedral intermediate destabilizes this species.
- Castro, Enrique A.,Cubillos, Maria,Ibanez, Fernando,Moraga, Inge,Santos, Jose G.
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p. 5400 - 5404
(2007/10/02)
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- THE SYNTHESIS OF o-NITROBENZENETHIOLS: AN ADVANTAGEOUS NUCLEOPHILIC DISPLACEMENT ON o-CHLORONITROBENZENES
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Reaction of substituted o-chloronitrobenzenes with sodium sulphide in DMSO occurs rapidly and gives the corresponding o-nitrobenzenethiols, following a convenient one-step pathway.Better yields are obtained when stoicheiometric amounts of sulphur, dissolved in a little carbon disulphide, are added in the presence of ethyl methyl ketone as solvent.
- Battistoni, Paolo,Bruni, Paolo,Fava, Gabriele
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p. 301 - 304
(2007/10/02)
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- Water-soluble trisazo 8-amino-naphthol-1 dyes
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Very effective direct dyeing of cotton and other hydroxyl- or nitrogen-containing fibers is effected with water-soluble triasazo dyes having the formula: where A is a radical of a diazoconstituent and A3 is a radical of a coupling constituent STR1 and A1 or A2 or both can have their azo linkages reversed. These dyes are very fast particularly to washing and to perspiration, and are so effective with cotton that dye baths for such use are rapidly exhausted and the disposal of used bath is less of a problem.
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