Showing papers on "Xanthene published in 1979"
TL;DR: It was confirmed that Phloxine and Rose Bengale had DNA-damaging capacity related to the mutagenecity and binding capacity of xanthene dyes with bovine serum albumin decreased.
Abstract: The toxicity of xanthene dyes were studied by various interaction between the dyes and the components in vital body. (1) An increase in the amount of Rose Bengale adsorbed on the gill of fish was followed by the increase in red corpuscle number, and it was assumed that the death of fish in xanthene dye solution was due to anoxemia. (2) Binding capacity of xanthene dyes with bovine serum albumin decreased in the following ; Rose Bengale, Phloxine, Erythrosine, Eosine and Uranine. This order was quite coincident with the toxicity compared by TLm values. (3) From the results of recassay test by use of Bacillus subtilis, it was confirmed that Phloxine and Rose Bengale had DNA-damaging capacity related to the mutagenecity.
12 citations
TL;DR: The xanthene merocyanine related to rhodamine B and fluorescein shows a slightly larger Stokes shift than either dye and lases at intermediate wavelengths.
12 citations
TL;DR: After deprotonation, xanthene reacts with equimolar amounts of the lacylaziridines 2a,b to yield the compounds 5a, b and 6a which carry one or two amidoethyl groups at position 9 as mentioned in this paper.
Abstract: Nach Deprotonierung wird Xanthen mit aquimolaren Mengen der N-Acylaziridine 2a,b ein- und zweimal in 9-Stellung zu den Verbindungen 5a,b und 6a,b amidoethyliert. Durch analoge Umsetzung mit 1-Ethoxycarbonylaziridin (2c) unter nachfolgender Erwarmung wird das Spiro[xanthen-9,3′-pyrrolidon] 8 erhalten.
Reactions with Aziridines, XVIII:2) Amidoethylation of Xanthene with N-Acylaziridines
After deprotonation, xanthene reacts with equimolar amounts of the l-acylaziridines 2a,b to yield the compounds 5a,b and 6a,b which carry one or two amidoethyl groups at position 9. The spiro[xanthene-9,3′-pyrrolidone] 8 is obtained analogously by reaction with 1-ethoxycarbonyl aziridine (2c) and subsequent heating.
6 citations
TL;DR: In this article, a method was described in which Amberlite XAD-2 is used as an adsorbent for the isolation of synthetic water-soluble food dyes and for the detection of the dyes by thin-layer chromatography.
5 citations
Abstract: Reactions of acids with vinylidenexanthenes (or thioxanthenes) 1 and 9-methoxy-9-vinylxanthenes (or thioxanthenes) 8 give xanthene- (or thioxanthene-) 9-spiro-1′-indenes 7. With bromine or sulfuryl chloride they give the corresponding 2′-halogenoxanthene- (or thioxanthene-)9-spiro-1′-indenes 5. Formation of such derivatives depends on preferential attack of the reagents on allenes 1 to give initially xanthylium (or thioxanthylium) ions 3 which cyclize. One π bond of the allenes 1 can be selectively reduced in acid media. Chemical and spectral evidence for these routes are presented.
4 citations
TL;DR: In this paper, the sensitized photo-oxidation (SPO) of aliphatic polyamides (PA) has been studied on the basis of comparing the kinetic curves of oxygen absorption, the accumulation of peroxides, main chain bond fractures and the comsumption of sensitizers.
Abstract: The sensitized photo-oxidation (SPO) of aliphatic polyamides (PA) has been studied on the basis of comparing the kinetic curves of oxygen absorption, the accumulation of peroxides, main chain bond fractures and the comsumption of sensitizers. The quantitative characteristics of the SPO have been determined. The photo-sensitization was carried out by non-chain oxidation with the following compounds: peroxides, aromatic ketones, quinones, phenolic-type anti-oxidants, variable valence metal salts, and xanthene dyes; all these had the same mechanism of photo-degradation of the polymer, and the kinetic curves for bond fracture showed the existance of an induction period. The results have been explained as due to the sensitization of the photo-oxidation by there compounds, which consists of a photo-initiation of the central marco-radical, i.e. ∼CH2CONHCHCH2∼ (P1); this cannot result main chain bond fracture of the PA. The decomposition of the macromolecules is explained by the features of the recombination mechanism of the P1O2 peroxide radicals.
3 citations
Patent•
24 Apr 1979TL;DR: In this article, a process for preparing aralkyl derivatives of xanthene dyes was described, where the xanthenes dye is initially reacted with a strong base such as an alkali metal hydroxide to form a salt of the dye which is then reacted with an aralky compound to form the aralklyated xanthene dye.
Abstract: There is described a process for preparing aralkyl derivatives of xanthene dyes wherein and now abandoned the xanthene dye is initially reacted with a strong base such as an alkali metal hydroxide to form a salt of the dye which is then reacted with an aralkyl compound to form the aralkylated xanthene dye.
3 citations
Patent•
13 Feb 1979
TL;DR: In this paper, Xanthene or thioxanthene compounds expressed by formula I: [R is H, (substituted) alkyl, alkenyl, or pheryl, etc.].
Abstract: PURPOSE:Xanthene or thioxanthene compounds expressed by formula I: [R is H, (substituted) alkyl, alkenyl, or (substituted) pheryl, etc.; X is oxygen or sulfur atom; A is (substituted)benzene ring; -SO2Z is bonded to the benzene or naphthalene ring; Z is (alkyl) amino, (substituted) anilino, or (substituted) phenoxy group, etc.].
2 citations
TL;DR: In this paper, the surface energy barrier under the present experimental conditions was discussed with the aid of the electrochemical measurement of the ZnO sinter, and it was observed that the photoreduction of Ag+ is accompanied by the photolysis of dye molecules.
Abstract: Quantum yields of from 0.235 to 0.385 have been determined for the reduction of Ag+ by the irradiation of 365 nm light on a ZnO surface in aqueous solutions containing 5×10−5 to 1×10−3 M AgClO4. It is proposed that these results can be interpreted by a reaction scheme based on the assumption that some conduction-band electron produced in the ZnO by the irradiation transfers to the Ag+ adsorbed on the ZnO surface. The surface-energy barrier under the present experimental conditions was discussed with the aid of the electrochemical measurement of the ZnO sinter. The photoreduction of Ag+ is optically sensitized by the addition of xanthene dyes, such as Uranine and Rhodamine B. In this case, it is observed that the photoreduction of Ag+ is accompanied by the photolysis of dye molecules. The apparent quantum yields (the number of reacted molecules/the number of photons absorbed in the suspension) of the dye-sensitized photoreduction of Ag+ and the photolysis of dye molecules are 0.015 and 0.007 for Uranine, a...
1 citations
TL;DR: Indene and fluorene were effectively carboxylated by employing the reagent system, 1,3-diphenylurea, potassium carbonate and carbon dioxide, in organic solvent at room temperature and atmospheric pressure.
Abstract: Indene, and fluorene were effectively carboxylated by employing the reagent system, 1,3-diphenylurea, potassium carbonate and carbon dioxide, in organic solvent at room temperature and atmospheric pressure, to produce indenemonocarboxylic acid and fluorene-9-carboxylic acid, respectively. Diphenylurea was almost quantitatively recovered unchanged. Cyclohexanone was slightly carboxylated by the similar procedure. But acetonitrile, acetophenone, dibenzylketone, diphenylmethane, and xanthene were scarcely carboxylated.
TL;DR: In this article, the bestrahlung von l:2-Gemischen aus den Indandionen (Ia) bzw. (Ib) and Xanthen (II) with Licht von Wellenlange A 400 nm fuhrt zu den entsprechenden Verbindungen (III)-(V); aus Ia entsteht zusatzlich das Hydroxyindanon (VI) (12% Ausb.).
Abstract: Die Bestrahlung von l:2-Gemischen aus den Indandionen (Ia) bzw. (Ib) und Xanthen (II) mit Licht von Wellenlange A 400 nm fuhrt zu den entsprechenden Verbindungen (III)-(V); aus (Ia) entsteht zusatzlich das Hydroxyindanon (VI) (12% Ausb.).
Patent•
03 Aug 1979
TL;DR: In this article, the authors presented chemical and spectral evidence for these routes and showed that one π bond of the allenes 1 can be selectively reduced in acid media, which is called preferential attack of the reagents on allenes.
Abstract: Reactions of acids with vinylidenexanthenes (or thioxanthenes) 1 and 9-methoxy-9-vinylxanthenes (or thioxanthenes) 8 give xanthene- (or thioxanthene-) 9-spiro-1′-indenes 7. With bromine or sulfuryl chloride they give the corresponding 2′-halogenoxanthene- (or thioxanthene-)9-spiro-1′-indenes 5. Formation of such derivatives depends on preferential attack of the reagents on allenes 1 to give initially xanthylium (or thioxanthylium) ions 3 which cyclize. One π bond of the allenes 1 can be selectively reduced in acid media. Chemical and spectral evidence for these routes are presented.