- ortho-Substituent effects on the in vitro and in vivo genotoxicity of benzidine derivatives
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Benzidine and its 3,3'-diamino, 3,3'-dimethyl, 3,3'-dimethoxy, 3,3'-difluoro, 3,3'-dichloro, 3,3'-dibromo, 3,3'-dicarbomethoxy and 3,3'-dinitro derivatives together with 2-nitrobenzidine and 3-nitrobenzidine were compared for their in vitro and in vivo genotoxicity. Relative mutagenicity was established with Salmonella strains TA98, TA98/1,8-DNP6 and TA100 with and without S9 activation. All the derivatives in the presence of S9 were more mutagenic than benzidine with 3,3'-dinitro- and 3-nitro-benzidine having the greatest mutagenicity. Mutagenicity in all 3 strains with S9 activation could be correlated to electron-withdrawing ability of substituent groups, as measured by the basicity of the amines. This correlation was explained on the basis that electron-withdrawing groups could favor the stability of the mutagenic intermediate N-hydroxylamine and also enhance the reactivityof the ultimate mutagenic species, the nitrenium ion. Mutagenicity was also correlated to the energy of the lowest unoccupied molecular orbitals (E(LUMO)). Hydrophibicity was found to have very limited effect on the relative mutagenicity of our benzidine derivatives. The in vivo endpoint was chromosomal aberrations in the bone-marrow cells of mice following intraperitoneal administration of benzidine and its derivatives. In contrast to the in vitro results, while all the amines were genotoxic in vivo, only the 3-nitro derivative had a significant increase in toxicity over benzidine.
- You,Brezzell,Das,Espadas-Torre,Hooberman,Sinsheimer
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- DIAMINE COMPOUND, POLYIMIDE PRECURSOR AND POLYIMIDE FILM PREPARED BY USING SAME
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The present invention discloses a novel diamine having a structure including an intramolecular imide group while having an aromatic ring group with a rigid structure. In addition, and by comprising the novel diamine as a polymerization component, the present invention can provide a polyimide film having improved mechanical and thermal properties while maintaining optical properties of polyimide.
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Paragraph 0250-0251; 0253; 0274-0275; 0277
(2020/09/26)
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- Synthetic method for 4,4'-dihalogenated-3,3'-dialkyl(alkoxyl) biphenyl compounds
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The invention relates to a synthetic method for 4,4'-dihalogenated-3,3'-dialkyl(alkoxyl) biphenyl compounds. The method employs o-nitro alkyl (alkoxyl) benzene as an initial raw material, 2,2'-dialkyl(alkoxyl) hydrazobenzene is prepared through catalysis hydrogenation in an alkaline environment, hydrochloric acid acidifying rearrangement is carried out, 4,4'-diamino-3,3'-dialkyl(alkoxyl) biphenyl is prepared, finally, a diazotization reaction is carried out and 4,4'-dihalogenated-3,3'-dialkyl(alkoxyl) biphenyl compounds are prepared. The synthetic method is advantaged by cheap and easily available raw materials, mild reaction conditions, simple operation, high safety coefficient, high yield and low cost.
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- Nanoporous metal oxides with tunable and nanocrystalline frameworks via conversion of metal-organic frameworks
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Nanoporous metal oxide materials are ubiquitous in the material sciences because of their numerous potential applications in various areas, including adsorption, catalysis, energy conversion and storage, optoelectronics, and drug delivery. While synthetic
- Kim, Tae Kyung,Lee, Kyung Joo,Cheon, Jae Yeong,Lee, Jae Hwa,Joo, Sang Hoon,Moon, Hoi Ri
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supporting information
p. 8940 - 8946
(2013/07/26)
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- Electrochemical oxidation of o-anisidine, p-anisidine, diphenylamine and o-toluidine at platinum electrode
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The oxidation of o-anisidine, p-anisidine, diphenylamine and o-toluidine was carried out at constant potential in non-aqueous system at platinum electrode. The electrolysis was carried out at controlled anodic potential in an electrochemical cell assembly containing reaction mixture, working as well as counter electrode and reference electrode. The oxidative products formed during the electrolysis of aromatic amines at platinum anode are discussed and reported here.
- Sharma, Laxmi Kant,Kumar, Sanjeev,Singh,Siddiqui
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experimental part
p. 1117 - 1123
(2011/05/05)
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- Functionalized Photoreactive Compounds
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The present invention concerns functionalized photoreactive compounds of formula (I), that are particularly useful in materials for the alignment of liquid crystals. Due to the adjunction of an electron withdrawing group to specific molecular systems bearing an unsaturation directly attached to two unsaturated ring systems, exceptionally high photosensitivities, excellent alignment properties as well as good mechanical robustness could be achieved in materials comprising said functionalized photoreactive compounds of the invention.
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- Regioselective [5,5]-sigmatropic rearrangement reactions of aryl hydrazides
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N,N′-Aryl hydrazides with substituents at the ortho or meta positions undergo highly regioselective [5,5]-sigmatropic rearrangement reactions to furnish benzidines in good to excellent isolated yields. The presence of single substituent at either the ortho or meta position provides sufficient bias, effectively suppressing the formation of diphenylene, the major byproduct of the conventional benzidine rearrangement reaction.
- Kang, Hong-Min,Lim, Young-Kwan,Shin, In-Jee,Kim, Hee-Yeon,Cho, Cheon-Gyu
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p. 2047 - 2050
(2007/10/03)
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- Formation of a carcinogenic aromatic amine from an azo dye by human skin bacteria in vitro
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Azo dyes represent the major class of dyestuffs. They are metabolised to the corresponding amines by liver enzymes and the intestinal microflora following incorporation by both experimental animals and humans. For safety evaluation of the dermal exposure of consumers to azo dyes from wearing coloured textiles, a possible cleavage of azo dyes by the skin microflora should be considered since, in contrast to many dyes, aromatic amines are easily absorbed by the skin. A method for measuring the ability of human skin flora to reduce azo dyes was established. In a standard experiment, 3 X 1011 cells of a culture of Staphylococcus aureus were incubated in synthetic sweat (pH 6.8, final volume 20 mL) at 28°C for 24 h with Direct Blue 14 (C.I. 23850, DB 14). The reaction products were extracted and analysed using HPLC. The reduction product o-tolidine (3,3'-dimethylbenzidine, OT) could indeed be detected showing that the strain used was able to metabolise DB 14 to the corresponding aromatic amine. In addition to OT, two further metabolites of DB 14 were detected. Using mass spectrometry they were identified as 3,3'-dimethyl-4-amino-4'-hydroxybiphenyl and 3,3'-dimethyl-4-aminobiphenyl. The ability to cleave azo dyes seems to be widely distributed among human skin bacteria, as, under these in vitro conditions, bacteria isolated from healthy human skin and human skin bacteria from strain collections also exhibited azo reductase activity. Further studies are in progress in order to include additional azo dyes and coloured textiles. At the moment, the meaning of the results with regard to consumer health cannot be finally assessed.
- Platzek,Lang,Grohmann,Gi,Baltes
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p. 552 - 559
(2007/10/03)
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- Basic azo dyestuffs of the 3-cyano-2,4,6-triamino pyridine series
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The new basic azo dyestuffs of the formula STR1 wherein the symbols have the meaning given in the description, are suitable for dyeing synthetic and naturally occurring substrates which can be dyed with basic dyestuffs.
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- Synthesis of phthalonitrile resins containing ether and imide linkages
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Imide-containing phthalonitrile monomers are prepared from a phthalonitrile and an aromatic dianhydride. The monomer and a method for preparing the monomer is disclosed. These monomers are synthesized into heat resistant polymers and copolymers with aromatic ring structure incorporating imide and ether linkages. The synthesis of the high temperature thermosetting polymers and copolymers is also disclosed.
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- Triazinyl reactive dyestuffs in which triazinyl group is further substituted with a beta-chloroethylsulfonyl- or vinylsulfonylbutyrylamino moiety
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Reactive dyes of the formula STR1 in which D is the radical of an organic dye of the monoazo, polyazo, metal complex azo, anthraquinone, phthalocyanine, formazan, azomethine, dioxazine, phenazine, stilbene, triphenylmethane, xanthene, thioxanthrone, nitroaryl, naphthoquinone, pyrenequinone or perylenetetracarbimide series, R is hydrogen or substituted or unsubstituted C1-4 -alkyl, X is a substituent which is detachable as an anion, B is a radical of the formula STR2 R1 and R2, independently of each other, are hydrogen or substituted or unsubstituted C1-4 -alkyl or phenyl, A is a substituted or unsubstituted aliphatic or aromatic bridge member, Y is a --CO--Z or --SO2 --Z radical, Z is an aliphatic, aromatic or heterocyclic reactive radical, and n is 1 or 2, are suitable for dyeing or printing cellulose-containing and nitrogen-containing materials and in high dyeing yield produce dyeings and prints having good fastness properties.
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- THE POLAROGRAPHIC AND VOLTAMMETRIC DETERMINATION OF TRYPANE BLUE
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The reduction of mutagenic bisazodye trypane blue has been studied at a mercury electrode, a mechanism has been proposed and optimal conditions found for its analytical application.The use of a dropping mercury electrode with a renewable surface yielded a detection limit of 8*10-7 mol l-1 for TAST polarography, and 8*10-8 mol l-1 for differential pulse polarography; the use of a hanging mercury drop electrode with an unrenewed surface during the measurement yielded detection limit of 6*10-8 mol l-1 for fast scan differential pulse voltammetry and4*10-8 mol l-1 for linear scan voltammetry.Preliminary adsorptive accumulation of the determined substance on the surface of the hanging mercury drop electrode led to a decrease in the detection limit to 5*10-9 mol l-1 for linear scan voltammetry.
- Barek, Jiri,Balsiene, Janina,Tietzova, Barbara,Zima, Jiri
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p. 921 - 928
(2007/10/02)
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- NITRO DERIVATIVES OF AROMATIC AZOXY COMPOUNDS. PART I. 2,2'- AND 4,4'-DIMETHYLAZOXYBENZENE NITRATION PRODUCTS
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By nitration of 2,2'-dimethylazoxybenzene (1) with concentrated nitric acid under conditions of increasing severity we obtained in succession nitro derivatives having their nitro groups in position: 4; 3',4 and 2,3',4.From 4,4'-dimethylazoxybenzene (2) we obtained similar products with nitro groups in positions: 2,3' (plus 2,6-isomer) and 2,3',6.Trinitro derivatives were obtained also by nitration of dinitro compounds, while tetranitro derivatives: 2,3',4,5' and 2,3',5',6 were obtained by nitrating trinitro compounds (in the presence of phosphoric acid).By reduction with stannous chloride in a strongly acidic medium we obtained, parallel to monocyclic aromatic amines and the conventional benzidine rearrangement products, also 4,4'-dimethyl-2,3'-diaminoazoxybenzene from dinitro derivative 2b, and 3,3'-dimethylbenzidine from mononitro derivative 1a, the latter being quite unexpected.
- Urbanski, Jerzy,Wolak, Ireneusz
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p. 1035 - 1045
(2007/10/02)
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- Silicone containing bis-thioether aromatic amines
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A silicone containing bis-thioether aromatic amine has a chemical structure wherein an aromatic nucleus at each end of the chemical radical is chemically bonded to the remainder of the chemical radical by either sulfur, sulfoxide or sulfone.
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- One step diazotization coupling process
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A process for producing metal-free azo pigments in purely organic liquid or aqueous/organic liquid containing at most 10% of water calculated on the total weight of the suspension is described. In this one-step process, a suitable aromatic amine is diazotized without isolation of the obtained diazo compound and coupled with a coupling component. Both reactions are carried out in purely or essentially organic medium. The latter consists essentially of such amount of an organic liquid that a substantial portion either of the diazo component or of the coupling component or of both these reactants remain undissolved. Both reactants must be free from sulphonic acid groups. If the resulting azo pigment contains carboxylic acid groups, these can be subsequently converted to the corresponding amido or ester groups.
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