- Efficient, facile metal free protocols for the bromination of commercially important deactivated aminoanthracene-9,10-diones
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Highly efficient, mild synthetic protocols were developed for the oxidative bromination of deactivated aminoanthracene-9,10-diones by using H2O2-HBr and m-CPBA-HBr in methanolic medium. Both the protocols offer excellent bromine atom economy, good conversion (100%) along with high yield (82–93%) and high purity of desired product. The N-alkylated amines undergo regio-selective bromination to give selective p-bromo product. The commercial availability of all the starting materials, simple reaction procedure and ease of work up, and easily amenable for scale up demonstrated commercial feasibility of both the protocols.
- Patil, Vilas V.,Gayakwad, Eknath M.,Patel, Khushbu P.,Shankarling, Ganapati S.
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supporting information
p. 2608 - 2613
(2017/06/13)
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- Synthesis and color properties of novel polymeric dyes based on grafting of anthraquinone derivatives onto O-carboxymethyl chitosan
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Four polymeric dyes were prepared by grafting brominated anthraquinone derivatives onto O-carboxymethyl chitosan through Ullmann condensation. The chemical structure of the prepared polymeric dyes was determined by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and differential scanning calorimetry (DSC), and the results showed that the anthraquinone derivatives were successfully grafted onto O-carboxymethyl chitosan. The grafting degrees of the four polymeric dyes were 0.66, 1.14, 0.93 and 1.01 mmol g-1 respectively. The color performance of brominated anthraquinone derivatives and prepared polymeric dyes was determined and compared using digital photographs and UV-Vis adsorption spectra, and it was found that the electronic properties and planarity of the substituent group in the anthraquinone derivatives obviously affected the adsorption wavelength of the prepared polymeric dyes. In addition, the polymeric dyes with an electron donating group and higher planarity showed longer adsorption wavelengths and more deep color. The cytotoxicity of prepared polymeric dyes was tested, and their IC50 values on human liver cell lines LO2 were 7.666, 8.557, 8.186 and 8.934 g L-1 respectively, suggesting low cytotoxicity of the prepared polymeric dyes.
- Lv, Dongjun,Cui, Jin,Wang, Yufang,Zhu, Guohua,Zhang, Mingjie,Li, Xiujing
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p. 33494 - 33501
(2017/07/13)
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- SYNTHESIS AND STRUCTURE OF 5-ACYLTHIO- AND 5-ACYLAMINO-6-OXO-6H-ANTHRAISOXAZOLES
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The action of 5-halogeno-6-oxo-6H-anthraisoxazoles on xanthates gave the corresponding 5-alkoxythiocarbonylthio-6-oxo-6H-anthraisoxazoles, for which the 1,10-quinonoid structure was confirmed.The initial product from the reaction of 5-chloro-6-oxo-6H-anthraisoxazole with potassium thiobenzoate, i.e., 5-benzoylthio-6-oxo-6H-anthraisoxazole, is unstable and was only detected spectrally.The acyl group in the obtained 5-acylamino-6-oxo-6H-anthraisoxazoles is also incapable of migration to the oxygen atom, and they therefore also exist in the 1,10-quinonoid form.
- Gornostaev, L. M.,Kuznetsov, I. A.,Arnol'd, E. V.,Shishova, L. V.
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p. 1352 - 1354
(2007/10/02)
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- REACTION OF 6-OXO-6H-ANTHRAISOXAZOLES WITH CYCLOHEXENE
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The reaction of 6-oxo-6H-anthraisoxazoles with cyclohexene in the presence of aluminum chloride leads to the corresponding 1-cyclohexylamino-9,10-anthraquinones.
- Gornostaev, L. M.,Medvedeva, S. A.
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p. 1547 - 1549
(2007/10/02)
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- Polymeric red colors
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Polymeric red colors having the structure STR1 wherein R1 and R2 are independently selected from among hydrogen, halos, lower alkyls, lower alkoxies, nitros, and sulfonates, R3 is selected from hydrogens, alkyls and alkylsulfonates, and R4 is an alkyl-containing polymer linking a plurality (n) of anthraquinones into a polymeric colorant are disclosed to be used as nonabsorbable colorants for edibles and cosmetics. They may also be used in such substrates as lakes.
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- Efficiency of ultrafiltration purification of solutions of polymeric colorants by inorganic base addition
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The ultrafiltration purification of aqueous solutions of polymeric colorants, wherein low molecular weight impurities are removed in an ultrafiltrate leaving a purified polymeric colorant-bearing retentate, is carried out with improved efficiency when during at least 2 diavolumes of ultrafiltration, the pH of the retentate is maintained above about pH 9.0.
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- TRANSFORMATIONS OF ANTHRAISOXAZOL-6-ONES IN HYDROHALIC ACIDS
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4-Halo-1-aminoanthraquinones are formed when anthraisoxazol-6-ones are refluxed in hydrohalic acids.The 3 position undergoes halogenation when 5-substituted isoxazoles are used.The process takes place via a one-proton mechanism with the participation of halide ion in the rate-determining step, possibly with the intermediate formation of N-haloaminoanthraquinones.
- Gornostaev, L. M.,Sakilidi, V. T.
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p. 1112 - 1114
(2007/10/02)
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- TRANSFORMATIONS OF 1-AZIDOANTHRAQUINONES IN HYDROHALIC ACIDS
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When heated in hydrohalic acids, 1-azidoanthraquinones are converted into 1-amino-4-halogenoanthraquinones.Under these conditions the 4-substituted azides are converted into the corresponding 2-halogeno-1-aminoanthraquinones.The kinetic data indicate the intermediate formation of N-halogenoaminoanthraquinones.
- Gornostaev, L. M.,Sakilidi, V. T.
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p. 562 - 565
(2007/10/02)
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- Red colors
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Red colors having the anthraquinone structure STR1 are disclosed wherein R1 and R2 are independently selected from among hydrogen, halos, lower alkyls, lower alkoxies, nitros, and sulfonates, and R3 and R4 are independently selected from hydrogens, alkyls and alkylsulfonates. Precursors are disclosed as well. In a preferred embodiment R4 is an alkyl-containing polymer linking a plurality of anthraquinones into a polymeric colorant especially useful as a nonabsorbable colorant for edibles.
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- Orange anthrapyridine monomeric colorants and colorant precursors
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Orange colors having the anthrapyridine structure STR1 are disclosed wherein R1 and R2 are independently selected from among hydrogen, halos, lower alkyls, lower alkoxies, nitros, and sulfonates, R3 and R4 are independently selected from hydrogens, alkyls and alkylsulfonates of 1 through 3 carbon atoms and R5 is a lower alkyl or lower alkyl sulfonate.
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- Polymeric aminoanthrapyridine orange colors
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Polymeric orange colors are disclosed having a noncrosslinked organic polymer backbone to which is covalently bonded a plurality of chromophores having a particular anthrapyridine structure. The colors are represented structurally as STR1 wherein R1 and R2 are independently selected from among hydrogen, halos, lower alkyls, lower alkoxies, nitros, and sulfonates; R3 is selected from hydrogen, alkyls and alkylsulfonates; R5 is a lower alkyl or lower alkyl sulfonate and R4 is a noncrosslinked organic polymer linking a plurality (k) of said anthrapyridines into a polymeric colorant. The polymeric colorants are especially useful as nonabsorbable orange colorants for edibles.
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- Water-soluble amine-linked polymeric colorants
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Polymeric colorants comprising a hydrocarbon backbone and attached directly thereto through amine linkages, at least one water-solubilizing group and at least one optically chromophoric group are disclosed. In a preferred embodiment, the backbone is a saturated aliphatic hydrocarbon, the chromophore is an anthraquinone chromophore and the solubilizing group is a sulfonate or sulfamate residue.
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