• Journal of the Korean Chemical Society
• /
• v.29 no.4
• /
• pp.441-447
• /
• 1985

Several benzanilides were prepared by acylation of anilines with substituted benzoyl chlorides. While 2-chlorobenzanilides were photocyclized, 2-methylbenzanilide and 2'-methylbenzanilide were cleaved to give photo-Fries type products. 2-Nitrobenzanilide and 2'-nitrobenzanilide were inert in the above conditions due to lowering energy of the excited state by the nitro group. N, N-dibenzoylaniline and N, N-di-(2-chlorobenzoyl) aniline gave photo-Fries type reaction products effectively. In the benzanilide photo-Fries type reaction the excited singlet state was believed to be involved, since no oxygen effect was observed on the reaction rate. Quantum yield for 2-methylbenzanilide is higher in nonpolar and less viscous solvents than in polar and viscous solvents. The solvent cage radical pair is suggested in the photo-Fries type reaction of benzanilides.

• Applied Chemistry for Engineering
• /
• v.4 no.3
• /
• pp.482-487
• /
• 1993

Organic nonlinear optical materials such as MNA(2-Methyl-4-nitro-aniline), Carbazole 1(5-Nitro-9-hydroxyethyl Carbazole), Carbazole 2(5-Nitro-9-ethyl Carbazole) and DR 1(Disperse Red 1) were incorporated into silica matrix to form a composite thin films. The thermal stability and degree of degradation were compared to these organic-inorganic composite film. Among those films, Carbazole 1 and DR 1 which have terminal -OH group showed enhanced stability for thermal degradation. The effect of polarization and degree of relaxation for the composite thin films incorporated with Carbazole 1 were measured by the absorbance change of UV spectra with time. With polarization treatment of Carbazole 1 incorporated composite film, the intensity of UV absorbance was remarkably reduced. And slow relaxation of Carbazole 1 molecule was suggested from the slightly recovered intensity of UV absorbance after removing the electric field at rooma temperature.

• Applied Chemistry for Engineering
• /
• v.10 no.7
• /
• pp.1079-1085
• /
• 1999

An investigation was made of the effect of various transition metal catalysts, ligands, and a promoter on the synthesis of N,N'-diphenylurea(DPU) from nitrobenzene, aniline, and carbon monoxide. Homogeneous Pd and Ni catalysts were found to be highly efficient, giving almost quantitative isolated DPU yields at 100% nitrobenzene conversion. Bidentate ligand, 1,3-bis(diphenylphosphino)proane(dppp) showed much improved activity and significantly different reactivity relative to the usual monodentate $PPh_3$ ligand in the presence of Ni and Pd catalysts. These results were inferred to the effect of the cis coordination of bidentate dppp ligand on the metal. The use of a promoter $Et_4NCl$ was indispensable in the case of $PPh_3$, yet inhibited the reaction if used with dppp. It was possible to reuse the Pd-dppp catalyst system, although the catalytic activity was reduced slowly.

• Polymer(Korea)
• /
• v.34 no.2
• /
• pp.154-158
• /
• 2010

We first synthesized N-phenylcyclotrisiloxazane ($D_3^{NPh}$) through a cyclization of $\alpha$,$\omega$- dichlorohexamethyltrisiloxane with aniline and prepared poly(dimethylsiloxane-co-N-phenylsiloxazane) copolymer (PDMS-NPSOX) by a ring opening copolymerization of them with hexamethylcyclotrisiloxane $D_3$. An acrylate monomer modified with PDMS-NPSOX was synthesized by using chloroethyl methacrylate and copolymerized with methylmethacrylate (MMA) and n-butylacrylate. The composition of the copolymer was chosen to control their glass transition temperature ($T_g$) to 25 $^{\circ}C$. By changing the comonomer from PDMS to PDMS-NPSOX, $T_g$ and adhesive strength of the copolymer were increased from 20 to 25 $^{\circ}C$ and from 1.76 to 2.23 N/cm, respectively.

• Toxicological Research
• /
• v.19 no.2
• /
• pp.105-114
• /
• 2003

TO evaluate an effect of cyclohexane treatment on the degree of liver damage, rats were induced liver damage with 10 or 17 times $CCl_4$ injection (0.1 m1/100 g body wt., 50% $CCl_4$ dis-solved in olive oil) at intervals of every other day. Cyclohexane (1.56 g/kg body wt., i.p.) was administrated to the animals at 48 hours after the last pretreatment of $CCl_4$ . Rats were sacrificed at 4 hours after injection of cyclohexane. On the basis of histopathological findings, liver weight/body weight (LW/ BW, %), activities of serum alanine aminotransferase (ALT), xanthine oxidase (XO) and akaline phosphatase (ALP), and contents of liver protein and manlondialdehyde (MDA), $CCl_4$ -pretreatment induced liver damage. And $CCl_4$ 17 times treated group showed more severe liver damage than $CCl_4$ 10 times treated group. Administration of one dose of cyclohexane to $CCl_4$ 10 times treated animals resulted in the enhanced liver damage; liver necrosis with proliferation of fibroblast and bile duct abnormality, and increase in hepatic MDA content and the activities of serum ALP and ALT, But the enhanced liver damage was not found in $CCl_4$ 17 times treated animals. Serum cyclohexanone concentrations at 4 or 8 hours after injection of cyclohexane were higher in all liver damaged groups than normal group and were somewhat higher In $CCl_4$ 17 times treated animals than $CCl_4$ 10 times treated ones. Among the oxygen free radical metabolizing enzymes, hepatic cytochrome P45O dependent aniline hydroxylase (CYPdAH) activity in cyclohexane metabolizing enzyme system was meaningfully increased by the injection of cyclohexane to the liver damaged rats, with increased Vmax and high affinity to aniline. LW/BW (%) and activities of serum XO and ALT were more significantly increased in liver damaged groups than normal group by administration of cyclohexanone. In conclusion, it is assumed that an enhancement of liver damage by injection of one dose of cyclohexane to liver damaged animals might be caused by oxygen free radicals and cyclohexanone.

• Analytical Science and Technology
• /
• v.14 no.1
• /
• pp.15-20
• /
• 2001

Photocatalytic $TiO_2$ films were prepared by anodic oxidation at 180 V and their structural difference caused by oxidation conditions was studies. The microstructure of $TiO_2$ films in $H_2SO_4$ and $H_2SO_4/H_2O_2$ solution was mixed type of rutile and anatase. However, the $TiO_2$ layer formed in $H_2SO_4/H_3PO_4$ and $H_2SO_4/H_3PO_4/H_2O_2$ mixture was mostly anatase type. All $TiO_2$ films prepared by anodic oxidation exhibited photocatalytic properties. The photocatalytic degradation of aniline blue was first order reaction with similar rate constants at all oxidative conditions examined in this work.

• Journal of the Korean Magnetic Resonance Society
• /
• v.3 no.2
• /
• pp.109-126
• /
• 1999

The location of Cu(II) exchanged into measoporous aluminosilicate MCM-41(AlMCM-41) material and its interaction with various adsorbate molecules were investigated by electron spin resonance and electron spin echo modulation spectroscopies. Cu(II) is fully coordinated to adsorbates in a wide open mesopore of AlMCM-41 for the formation of favorable complexes. It was found that in the fresh hydrated material, Cu(II) is octahedrally coordinated to six water molecules as evidenced by an isotropic room temperature ESR signal. This species is located in a cylindrical MCM-41 channel and rotates rapidly at room temperature. Evacuation at room temperature removes some of these water molecules, leaving the Cu(II) coordinated to less water molecules and anchored to oxygens in an MCM-41 channel wall. Dehydration at 450$^{\circ}C$ produces one Cu(II) species located on the internal wall of a channel, which is easily accessible to adsorbates. Adsorption of adsorbate molecules such as water, methanol, ammonia, pyridine, aniline, acetonitrile, benzene, and ethylene on a dehydrated Cu-AlMCM-41 material causes changes in the ESR spectrum of Cu(II), indicating the complex formation with these adsorbates. Cu(II) forms a complex with six molecules of methanol as evidenced by an isotropic room temperature ESR signal and ESEM analysis like upon water adsorption. Cu(II) also forms a square planar complex containing four molecules of N-containing adsorbates such as ammonia, pyridine and aniline based on resolved nitrogen superhyperfine interaction and their ESR parameters. However, Cu(II) forms a complex with six-molecules of acetonitrile based on ESR parameters. Only one molecule of benzene or ethylene is coordinated to Cu(II).

• Journal of the Korean Chemical Society
• /
• v.43 no.6
• /
• pp.670-675
• /
• 1999

6-[1-(4-Ribitylanilino)ethyl]-1,3,7-trimethyllumazine (2), which is related to pteridine moiety of methanopterin, was synthesized. 4-Ribitylaniline derivative was prepared from D-ribose and N-benzoyl-4-bromoaniline (7) as the starting materials through several steps. 6-Acetyl-1,3,7-trimethyllumazine (4) was obtained from the reaction of 4-amino-1,3-dimethyI-5-nitrosouracil (3) with 2,4-pentanedione by Timmis reaction. Compound 4 was converted to 6-(1-chloroethyl)-1,3,7-trimethyllumazin (6) by the reduction with sodium borohydride and followed by chlorination with thionyl chloride. The nucleophilic displacement reaction of compound 6 with 4-(2,3:4,5-di-O-iso-propylidene-D-ribityl)aniline (13) in anhydrous DMF yielded 6-[1-{4-(2,3:4,5-di-O-isopropylidene-D-ribityl)anilino}ethyl]-1,3,7-trimethyllumazine (14). The target molecule 2 was obtained by the hydrolysis of compound 14 in the presence of an acid catalyst.

• Korean Chemical Engineering Research
• /
• v.47 no.2
• /
• pp.248-257
• /
• 2009

In this paper, human exposure and risk of environmental pollutants were predicted using an emission assessment model and multimedia fate model. Eight environmental pollutants, acetaldehyde, acrylonitrile, aniline, benzene, carbon tetrachloride, dichloromethane, formaldehyde and vinyl chloride, were selected for the risk assessment in an urban and industrial area in Korea. The emission rate of target pollutants were estimated after considering a variety of point and non-point emission sources including geographical information. A spatially refined multimedia fate model was applied to predict the environmental concentration and fate of pollutants. Hazard data of target materials were obtained from the IRIS(Integrated Risk Information System) database. Using the modeling results with hazard data, the human risks were assessed. Modeling results demonstrate that the considerable risks were observed for several pollutants.

• Toxicological Research
• /
• v.11 no.2
• /
• pp.247-252
• /
• 1995

To evaluate the effect of xanthine oxidase on liver injury by $CCl_4$, liver damage was induced both in allopurinol pretreated rats (500 mg/kg. ip) and control group by twice intraperitoneal injection of $CCl_4$ (0.1 ml/100 g body wt. 50% in olive oil) at interval of one day. Increases in the levels of serum alanine aminotransferase and liver weight/body weight (%) by $CCl_4$ were significantly smaller inallopurinol pretreated rats than in control whereas the hepatic microsomal glucose-6-pholphatase activities were significantly higher in allopurinol pretreated rats than control group by $CCl_4$ treatment. These results indicates that allopurinol pretreatment may reduce the liver damage in $CCl_4$ intoxicated rats. In rats either with $CCl_4$or not, hepatic type O xanthine oxidase activities were significantly reduced by allopurinol pretreatment and the increasing rate of these enzymes to each control was remarkably lower in allopurinol pretreated rats than control. Liver cytosolic protein contents and aniline hydroxylase, aminopyrine demethylase activities were higher in allopurinol pretreated rats than coirol rats when animals were treated with $CCl_4$. On the other hand, neither allopurinol pretreated nor $CCl_4$ treatment caused any significant changes in hepatic superoxide dismutase and catalase activities. Hepatic glutathione contents were higher in $CCl_4$-treated rats than control, but no significant changes were found in both between the allopurinol treated rats and $CCl_4$-treated rats pretreated with allopurinol, and glutathione and glutathione S-transferase activities were significantly reduced in $CCl_4$-treated rats than control whereas these enzyme activities showed on significant change in both between allopurinel treated and $CCl_4$-treated rats pretreated with allopurinol. It is concluded that xanthine oxidase reaction system augment $CCl_4$ induced liver injury via even oxygen free radical system.