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3,3'-Dinitrophenolsulphonephthalein : an acid–base indicator dye with unusual properties / Nicolay O. Mchedlov-Petrossyan in COLORATION TECHNOLOGY, Vol. 133, N° 2 (04/2017)
[article]
Titre : 3,3'-Dinitrophenolsulphonephthalein : an acid–base indicator dye with unusual properties Type de document : texte imprimé Auteurs : Nicolay O. Mchedlov-Petrossyan, Auteur ; Anna N. Laguta, Auteur ; Sergey V. Shekhovtsov, Auteur ; Sergey V. Eltsov, Auteur ; Tatyana A. Cheipesh, Auteur ; Irina V. Omelchenko, Auteur ; Oleg V. Shishkin, Auteur Année de publication : 2017 Article en page(s) : p. 135-144 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cellules
Chromatographie en phase liquide à hautes performances
Colorants -- Synthèse
Etude in vitro
Photochimie
Spectrométrie de masse
Structure moléculaire
ThiolsIndex. décimale : 667.2 Colorants et pigments Résumé : This paper is devoted to the phenolsulphonephthalein nitro derivative 3,3'-dinitrophenolsulphonephthalein, also called nitrophenol violet (NPV). The neutral molecular form, H2R, was isolated as a sultonic tautomer, and an X-ray crystal structure analysis was carried out. UV-vis absorption spectra in methanol, DMSO, acetonitrile, and water at different pH values were ascribed to the molecular and anionic (H2R, HR-, and R2-) species. Whereas the pKa values of this acid–base indicator (HR- urn:x-wiley:14723581:media:cote12254:cote12254-math-0001 R2- + H+) in water and DMSO are close to those of 3,3',5,5'-tetrabromophenolsulphonephthalein (or bromophenol blue), replacing the four Br atoms with two NO2 groups results in a pronounced tendency to carbinol formation. In weakly acidic aqueous media, the HR- anion slowly converts into the colourless carbinol H2ROH-. The latter is transformed to the orange carbocation only in concentrated (70-94 wt%) sulphuric acid. The formation of H2ROH- is atypical for the common sulphonephthalein indicators and should be ascribed to the enhanced positive charge density on the nodal carbon atom. The reaction mechanism and kinetic equation explaining this pH-dependent process are proposed, in addition to a kinetic study of the common process R2- + HO- -> ROH3- in the alkaline region. The numerical characterisation of the protolytic processes obtained for NPV is also helpful in gaining a better understanding of the properties of previously studied 3,3',5,5'-tetranitrophenolsulphonephthalein, which is much less accessible for a quantitative description. Note de contenu : - EXPERIMENTAL : General - Synthesis - Photochemical experiments - Studies of the spectroscopic response of the dyes to thiols - UPLC/MS analyses - Determination of cell viability and studies of the response to thiols in living cells
- RESULTS AND DISCUSSION : Synthesis and spectroscopic studies - Studies of the spectroscopic response to thiols - UPLC and mass spectral analyses of products formed in the reaction with L-Cys - Cell viability and response to thiols in vitroDOI : 10.1111/cote.12254 En ligne : https://drive.google.com/file/d/1korHDoZ5IQTDhl4kyBlpyXX3OPlzMqdG/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=28227
in COLORATION TECHNOLOGY > Vol. 133, N° 2 (04/2017) . - p. 135-144[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 18801 - Périodique Bibliothèque principale Documentaires Disponible Peculiarities of the 4,5-dinitrofluorescein esters synthesis : formation of reduced species / Sergey V. Shekhovtsov in COLORATION TECHNOLOGY, Vol. 138, N° 2 (04/2022)
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Titre : Peculiarities of the 4,5-dinitrofluorescein esters synthesis : formation of reduced species Type de document : texte imprimé Auteurs : Sergey V. Shekhovtsov, Auteur ; Elena H. Shvets, Auteur ; Maksim A. Kolosov, Auteur ; Iryna V. Omelchenko, Auteur ; Anastasiia S. Batrak, Auteur ; Nikolay O. Mchedlov-Petrossyan, Auteur Année de publication : 2022 Article en page(s) : p. 192-200 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Colorants -- Synthèse
Esters -- Synthèse
FluorescenceIndex. décimale : 667.2 Colorants et pigments Résumé : The problem of synthesising esters of fluorescein dyes has long been solved for the mother compound and its derivatives. The choice of an optimal method depends on the substituents in the xanthenes moiety and in the phthalic acid residue. To obtain alkyl esters of 4,5-dinitrofluorescein, we used thionyl chloride in ethanol. However, several other products appeared, which were identified as reduced species resulting from hydride transfer. A similar picture was observed when using sulphuric acid instead of thionyl chloride. The formation of reduced species was demonstrated by hydrogen-1 and carbon-13 nuclear magnetic resonance spectroscopy and X-ray analysis. In methanol, on the other hand, the esterification of the carboxylic group proceeds easily and with good yield. In the course of the current study, four new compounds of the fluorescein series were synthesised and characterised. The results show that nitro substitution in xanthenes favours dye reduction. Note de contenu : - Materials
- Apparatus
- X-ray diffraction
- Synthesis
- Preparative TLCDOI : https://doi.org/10.1111/cote.12582 En ligne : https://onlinelibrary.wiley.com/doi/epdf/10.1111/cote.12582 Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37850
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Code-barres Cote Support Localisation Section Disponibilité 23518 - Périodique Bibliothèque principale Documentaires Disponible Revisiting tetranitrophenolsulfonephthalein / Nicolay O. Mchedlov-Petrossyan in COLORATION TECHNOLOGY, Vol. 131, N° 3 (06/2015)
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Titre : Revisiting tetranitrophenolsulfonephthalein Type de document : texte imprimé Auteurs : Nicolay O. Mchedlov-Petrossyan, Auteur ; Kateryna V. Roshchyna, Auteur ; Sergey V. Shekhovtsov, Auteur ; Sergey V. Eltsov, Auteur ; Oleksii S. Zozulia, Auteur ; Irina V. Omelchenko, Auteur ; Oleg V. Shishkin, Auteur Année de publication : 2015 Article en page(s) : p. 236-244 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Colorants -- Synthèse
NitrophénolsIndex. décimale : 667.2 Colorants et pigments Résumé : Among the vast series of phenolsulfonephthalein dyes, the nitro derivatives and especially 3,3?,5,5?-tetranitrophenolsulfonephthalein (nitrophenol crimson) remain practically unexplored, whereas the halogen and alkyl derivatives have been studied comprehensively. This striking difference is probably due to the enormous influence of the four NO2 groups on the properties of the dye. As a result, the protolytic behaviour is unlike even that of tetrabromo phenolsulfonephthalein, and the recognised scheme of acid–base and tautomeric equilibrium of the sulfonephthaleins is unable to explain it. The molecular form H2R was isolated as a sultonic tautomer, and an X-ray crystal structure analysis was carried out. Our studies of the UV-vis absorption spectra in water, methanol, dimethyl sulfoxide, acetonitrile, acetone, and dichloromethane, as well as in aqueous micellar solutions of surfactants, allowed us to evaluate the true molar absorptivity of the dianion R2?, and to elucidate the enormous tendency to form yellow trianionic carbinol ROH3?, even in the presence of traces of H2O. Nuclear magnetic resonance and electrospray data confirm the proposed scheme of ionisation and tautomerism of nitrophenol crimson. Note de contenu : - EXPERIMENTAL : Materials - Synthesis of the dye - Apparatus - Kinetic measurements
- RESULTS AND DISCUSSION : The structure of the dye in the solid state - Nitrophenol crimson in water - Nitrophenol crimson in organic solvents - Examining nitrophenol crimson solutions by the electrospray method - The monoanion problemDOI : 10.1111/cote.12145 En ligne : https://onlinelibrary.wiley.com/doi/epdf/10.1111/cote.12145 Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24126
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Code-barres Cote Support Localisation Section Disponibilité 17231 - Périodique Bibliothèque principale Documentaires Disponible The molecular structure of anionic species of 2,4,5,7-tetranitrofluorescein as studied by electrospray ionisation, nuclear magnetic resonance and X-ray techniques / Nicolay O. Mchedlov-Petrossyan in COLORATION TECHNOLOGY, Vol. 134, N° 5 (10/2018)
[article]
Titre : The molecular structure of anionic species of 2,4,5,7-tetranitrofluorescein as studied by electrospray ionisation, nuclear magnetic resonance and X-ray techniques Type de document : texte imprimé Auteurs : Nicolay O. Mchedlov-Petrossyan, Auteur ; Klaus Steinbach, Auteur ; Natalya Vodolazkaya ; Denis V. Samoylov ; Sergey V. Shekhovtsov ; Irina V. Omelchenko ; Oleg V. Shishkin Année de publication : 2018 Article en page(s) : p. 390-399 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Analyse spectrale
Colorants -- Analyse
Nitrofluorescéine
PulvérisationIndex. décimale : 667.3 Teinture et impression des tissus Résumé : Among the fluorescein dyes, the behaviour of their nitro derivatives in solution is most unusual, and yet at the same time rarely studied. In this study, their 13C nuclear magnetic resonance and electrospray spectra are reported, which confirm, in concert with their ultraviolet-visible spectra, the molecular structures of the neutral and ionic species of 2,4,5,7-tetranitrofluorescein observed in different solvents and at various pH values. A peculiar property of this dye consists in its lactonisation of the double-charged anion, contrary to the well-known coloured and fluorescent dianions of fluorescein, eosin, etc. Also, this dianion-lactone exhibits high ability for opening the pyran ring. This cleavage takes place at much lower pH values as compared with those for fluorescein and its halogen derivatives. The ruptured species can be formed as either lactone or carbinol ; the latter appears as a result of the nucleophilic attack of a HO- on the central carbon atom. The corresponding molecular structures are identified via the electrospray method and X-ray analysis. The behaviour of some other nitrofluoresceins in alkaline media is also considered. Note de contenu : - EXPERIMENTAL : Materials - Apparatus
- RESULTS AND DISCUSSION : Electronic spectra - C NMR spectra - Electrospray studies - X-ray studies of th ehighly alkaline forms of TNF - The behavious of other nitrofluoresceins, fluoresceins and phtaleins in aqueous alkaline mediaDOI : 10.1111/cote.12351 En ligne : https://onlinelibrary.wiley.com/doi/epdf/10.1111/cote.12351 Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=31164
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Code-barres Cote Support Localisation Section Disponibilité 20217 - Périodique Bibliothèque principale Documentaires Disponible