• Journal of the Korean Chemical Society
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• v.14 no.1
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• pp.119-122
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• 1970

In those six kinds of diamine salt crystal of which their structures had already been determined up to date, commonly one molecule of diamine and two molecules of acid were combined; although the crystal of benzidine perchlorate, only one molecule each of benzidine and perchloric acid were combined. At the case of benzidine perchlorate, one molecule acts as the role of two molecules by coincidence of the center of symmetry point of both the lattice and molecule, and perchlorate ion is locating symmetrically between two -$NH_2$ groups of different benzidine molecule, therefore benzidine and acid could be combined together with 1:1 by mole ratio. When forming the salt with diamine and acid, the combining mole ratio would be determined in accordance with the relationship between the symmetry element that presented by the space group and the symmetry element of diamine salt melecule.

• Bulletin of the Korean Chemical Society
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• v.13 no.6
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• pp.680-683
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• 1992

The electrochemistry of benzidine and hydrazobenzene was studied in water-acetonitrile mixed solutions at various pHs and the results are reported. The cyclic voltammetric peak for the oxidation of benzidine shows a pH dependency of -62 mV/pH in the pH range of 0-3.5, no pH dependency between pH values of 3.5 and about 10.5, and of about -50 mV/pH between pH=10.50 and 14.0, indicating that oxidation mechanisms differ depending on the pH of the medium. However, the CV peak for the hydrazobenzene oxidation is shown to be independent of pH of the medium, suggesting that the proton is not involved in the rate limiting step of the electrochemical oxidation of hydrazobenzene to azobenzene. Results of in situ spectroelectrochemical experiments indicate that the oxidation products obtained during the oxidation of benzidine and hydrazobenzene depend on the result of dynamic equilibria taking place at various pHs.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.2
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• pp.100-109
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• 1999

This study evaluates the pretreatment for analysis of benzidine metabolites in urine by measuring the recovery rates according to the temperature and periods of storage of the urine. By the solid phas e extraction, the recovery rates of basic hydrolysis are benzidine 67.4 %, monoacetylbenzidine 105.1 %, and diacetylbenzidine 115.8 %, respectively. By the liquid extraction, the recovery rates of back-extraction into 0.1 M perchloric acid are benzidine 105.7%, monoacetylbenzidine 94.2 %, diacetylbenzidine 72.8 %, respectively. The difference of the recovery rates between the back-extraction into 0.1 M HCl and 0.1 M perchloic acid after basic hydrolysis are 101 % and 98.8 %, respectively. When the recovery rates of the urinary s amples of pH 3, pH 7, pH 12 at $25^{\circ}C$ and $-76^{\circ}C$ are compared for four weeks, there are no differences according to the temperature and the periods of storage. The above results show that the solid phase extraction and back-extraction by 0.1 M perchloric acid after basic hydrolys is are suitable for the analysis of benzidine metabolites. There are no difference of the recovery rates of the urinary samples stored at $25^{\circ}C$ and $-76^{\circ}C$ at pH 3, pH 7, pH 12, respectively for 28 days.

• Journal of Preventive Medicine and Public Health
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• v.35 no.3
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• pp.229-235
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• 2002

Objectives : To evaluate the effects on the formation of benzidine-hemoglobin, and benzidine metabolite-hemoglobin adducts, caused by pretreatment with the known xenobiotic metabolism effectors, ethanol and phenobarbital, in rats administered Direct Black 38 dye. Methods : The experimental rats were divided into three groups: a control group, an ethanol group and a phenobarbital group. Rats were pretreated with ethanol (1g/kg) or phenobarbital (80mg/kg) 24 hours prior to the oral administration of Direct Black 38 (0.5mmol/kg), with the control group being administered the same amount of distilled water. Blood samples were obtained from the vena cava of 5 rats from each group prior to, and at 30 min, 3h, 5h, 9h, 12h, 24h, 48h, 72h, 96h, and 144h following the oral administration of Direct Black 38. Directly after sampling the blood was separated into hemoglobin and plasma, with the adducts being converted into aromatic amines by basic hydrolysis. Hydrolyzed benzidiene, monoacetylbenzidine and 4-aminobiphenyl were analyzed by reverse-phase liquid chromatography with an electrochemical detector, The quantitative amount of the metabolites was expressed by the hemoglobin binding index (HBI). Results : In the ethanol group, benzidine-, monoacetylbenzidine-, and 4-aminobiphenyl-HBI were increased to a greater extent than those in the control group. These results were attributed to the ethanol inducing N-hydrgxylation, which is related to the formation of the hemoglobin adduct, In the phenobarbital group, all the HBIs, with the exception of the benzidine-HBI, were increased to a greater extent than those of the control group. These results were attributed to the phenobarbital inducing N-hydroxylation related to the formation of the hemoglobin adduct. The N-acetylation ratio was only increased with the phenobarbital pretreatment due to the lower benzidine-HBI of the phenobarbital group compared to these of the control and ethanol groups. The N-acetylation ratios for all groups were higher than f for the duration of the experimental period. Although the azo reduction was unaffected by the ethanol, it was inhibited by the phenobarbital, The ratio of the benzidine-HBI in the phenobarbital group was lower than those of the ethanol the control groups for the entire experiment. Conclusion : Our results indicate that both ethanol and phenobarbital increase the formation of adducts by the induction of N-hydroxylation, but also induced N-acetylation. Phenobarbital decreased the formation of benzidine-HBI due to the decrease of the azo reduction. These results suggest that the effects or ethanol and phenobarbital need to be considered in the biochemical monitoring of Direct Black 38.

• Journal of the Korean Chemical Society
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• v.14 no.1
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• pp.123-126
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• 1970

The approximate crystal structure of benzidine monoperchlorate has been determined by single crystal X-Ray diffraction technique and patterson method. As the molecule has a center of symmetry in it and location of perchlorate ion is symmetrically on the mirror plane in the unit cell, perchlorate ion is forming hydrogen bond with two -$NH_2$ groups in the different molecule. Thus, one molecule of benzidine and perchloric acid combines 1:1 by mole ratio.

• Fibers and Polymers
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• v.3 no.4
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• pp.140-146
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• 2002

Non-genotoxic diamines 2,2'-dimethyl-5,5'-dipropoxybenzidine and 5,5'-dipropoxy-benzidine were employed as potential alternatives to benzidine in the synthesis and evaluation of new direct dyes for cotton. Assessment of the resultant dyes indicated that both diamines can be used to prepare new direct dyes having colors and fastness properties that make them comparable to commercial direct dyes, and that the structures of the new direct dyes can be confirmed by negative ion electrospray mass spectrometry (ESMS). The mutagenic properties of new direct dyes were established using the standard Ames Salmonella mammalian mutagenicity assay.

• Fibers and Polymers
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• v.6 no.3
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• pp.235-243
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• 2005

A series of new metallized direct dyes based on benzidine congeners, 2,2'-dimethyl-5,5'-dipropoxybenzidine and 5,5'-dipropoxybenzidine, were evaluated for mutagenicity in Salmonella typhimurium strains TA98 and TA 100. All of the dyes examined were judged to be non-mutagenic with and without metabolic activation while toxicity was seen in some dyes at high doses. The study also suggested that the standard Salmonella mutagenicity plate-incorporated assay was an excellent method for evaluation of dyes for mutagenicity.

• Fibers and Polymers
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• v.6 no.4
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• pp.297-305
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• 2005

A series of new direct dyes based on benzidine congeners, 2,2'-dimethyl-5,5'-dipropoxybenzidine and 5,5'-dipropoxybenzidine, were evaluated for mutagenicity in Salmonella typhimurium strains TA98 and TA100. All of the dyes examined were judged to be non-mutagenic with and without metabolic activation while toxicity was seen in some dyes at high doses. The study also suggested that the standard Salmonella mutagenicity plate-incorporated assay was an excellent method for evaluation of direct dyes for mutagenicity.

• Journal of the Korean Chemical Society
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• v.16 no.1
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• pp.18-24
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• 1972

Benzidine dihydrochloride crystallizes in the triclinic system. The space group is $P_1$. The unit cell dimensions are; a = 4.38${\pm}$0.01, b = 5.76${\pm}$0.01, c = 12.82${\pm}$0.02${\AA}$, $\alpha$ = 101.5${\pm}$0.2, $\beta$ = 99.5${\pm}$0.2, $\gamma$ = 99.5${\pm}$0.2$^{\circ}$; with one molecule per unit cell. The crystal structure has been solved by two dimensional Patterson and by trial and error methods, and refined by means of two dimensional differential synthesis. The bond distances are C-C(*) = 1.40${\pm}$0.02, C-C = 1.52${\pm}$0.02, C-N = 1.51${\pm}$0.03 and N-H${\cdot}{\cdot}{\cdot}$Cl = 3.21${\pm}$0.03${\AA}$. The structure consists of hydrogen bonded molecular layers, extending to the (100) plane, and the hydrogen bonding scheme is similar to that of p-phenylenediamine dihydrochloride. The adhesion between hydrogen bonded molecular layers is due to van der Waals forces.

• Macromolecular Research
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• v.11 no.6
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• pp.458-466
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• 2003

Several copolyimides have been synthesized with different combinations of comonomers in order to study the relationship between conductivity and water insolubility. m-Phenylenediamine (m-PDA), an angled comonomer, was introduced into the polymer backbone to increase water absorption, and resulted in higher proton conductivity. 2,2-bis(trifluoromethyl)benzidine (TFMB) was used as the comonomer to promote water insolubility. There is a good correlation between the water uptake and conductivity of the polyimides. The copolyimides that had high water uptake also generated high proton conductivity. Those polyimides had good mechanical properties. The copolyimides that have 27 mol% of TFMB and 9 mol% of m-PDA have reasonable conductivities and are insoluble in water at 90$^{\circ}C$, even though they have lower conductivities than those of the homopolymer.