• Textile Coloration and Finishing
• /
• v.9 no.6
• /
• pp.1-9
• /
• 1997

Four aminoazobenzene disperse dyes derived from different N-ethyl-N-substitutedalkylanilines and 2-chloro-4-nitroaniline, were synthesized and their chemical structure were analyzed by 500 MHz NMR spectroscopy. The wavelength of maximum absorption of the synthesized dyes, which was dependent on the electron withdrawing ability of the substituent, was in the range of 499.5~526.0nm. As terminal substituent became polar, the dyeing rate of disperse dye increased, and the exhaustion rate of dyes having cyano or hydroxy group became lower, that of the dye having acetoxy group higher. The wash fastness of polyester fabric dyed with disperse dyes possessing the polar group improved probably due to the increased dye-fiber interaction.

• Journal of the Korean Applied Science and Technology
• /
• v.13 no.1
• /
• pp.47-54
• /
• 1996

Cinnamoyl ester(PGEFC) of poly(phloroglucinol-formaldehyde) glycidyl ether which has photosensitive functional group was prepared to apply to photoresist. Photosensitivity of PGEFC was estimated by the solubility difference in organic solvent before and after exposure to light. The yield of residual film was calculated by immersing the sample-coated quartz plates in the solvent which was used in coating. The yield of the residual film which was closely related to the sensitivity of the film, was affected by the degree of polymerization of the backbone resin, sensitizers and their concentration. The sensitivity was depended upon the degree of polymerization. Most of effective sensitizer for PGEFC among the sensitizers was 2, 6-dichloro-4-nitroaniline.

• Bulletin of the Korean Chemical Society
• /
• v.19 no.6
• /
• pp.689-695
• /
• 1998

Carbobenzoxy-alanyl-thiaarginine benzyl ester and carbobenzoxy-alanyl-thialysine benzyl ester were synthesized in solution. Kinetic studies were carried out using three different analytical methods, semi-classical method, progress curve analysis and competitive spectrophotometry. In competitive spectrophotometry, carbobenzoxy-valyl-glycyl-arginyl-p-nitroaniline was used as a detector. Kinetic constants such as $K_m$ and $V_{max}$ measured by competitive spectrophotometry are almost the same as those values measured by semi-classical method. Colorimetric Ellman's assays showed the thio-peptido mimetics to be a suitable substrates for trypsin. Kinetic studies with trypsin gave $K_m$ of 2.33 mM and $k_{cat}$ of $1.50{\times}10^5\;min^{-1}$ for carboxy-alanyl-thiaarginine benzyl ester and $K_m$ of $3.41{\times}10^{-3}\; Mm\; and\; k_{cat}\; of\; 520{\times}102\; min^{-1}$ for carbobenzoxy-alanyl-thialysine benzyl ester, respectively. Kinetic constants $(K_m=2.04{\times}10^{-2}\; mM, K_{cat}=4.42{\times}10^3 \;min^{-1})$ for natural substrate, carbobenzoxy-alanyl-lysine benzyl ester, were also evaluated by competitive spectrophotometry in order to compare the mode of binding on trypsin.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.4
• /
• pp.479-483
• /
• 2003

The reactions of 2,5-bis(ethynyldimethylsilyl)thiophene (1) with aromatic dihalides(1,4-dibromobenzene, 4,4'- dibromobiphenyl, 9,10-dibromoanthracene, 2,5-dibromopyridine, 2,5-dibromothiophene, and 2,6-diiodo-4- nitroaniline) were carried out in the presence of a $[(PPh_3)_2PdCl_2]$-CuI catalyst in refluxing triethylamine to give poly{[2,5-bis(ethynylenedimethylsilylene)thienylene](arylene)} (2-7) with molecular weights of 2200-7400. The oligomers reveal characteristic absorption in the UV/visible region. The thermal behavior of 2-7 was examined by thermogravimetric analysis in an argon atmosphere.

• Journal of the Korean Chemical Society
• /
• v.14 no.3
• /
• pp.207-212
• /
• 1970

A large variety of weed killers, insecticides, and bactericiedes on the market today are of almost infinite variety, but their pharmacological effects are different from each other according to the objects to cope with. Therefore, it is hoped that some chemical substance which serves as weed killer, an insecticide, and a bactericede at a same time, should be synthesized, in order to save expense and labor. I anticipated that the desire would be met by introducing to a molecule the radical which has the three effects. Here, I made an attempt of introducing $Cl_2$ gas to aniline considering the following respects: 1. Introduction velocity of $Cl_2$ gas under the varied temeratures and velocities of $Cl_2$ gas 2. The effect of reaction period under the condition which gives the most satisfactory yield. 3. The actions of catalysts, $SbCl_3$, $FeCl_3$, and $MoCl_5$, and their proportions when a mixture of the three catalysts is used in producing 2,6-dichloro-aniline. After consideration of above phenomena, the maximum production rate of 79.5% of 2.6-compound was obtained. With the compound I synthesized 2.6-dichloro-4-nitroaniline-mercuric acetate. Investigations of the effects of the compound as weed killer, an insecticide, and a bactericide showed that the compound, 2,6-dichloro-4-Nitro Aniline mercuric acetate has a satisfactory herbi-insecti-bactericidal effect.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.2
• /
• pp.309-314
• /
• 2009

New poly(arylene-ethynylene)s with silicon-containing ferrocene moiety in the polymer main chain were synthesized via the C-C bond forming reactions of 1,1´-bis(ethynyldimethylsilyl)ferrocene and various aromatic dihalides in high yields. The aromatic dihalides include 1,4-dibromobenzene, 4,4´-dibromobiphenyl, 9,10-dibromoanthracene, 2,5-dibromopyridine, 2,5-dibromothiophene, and 2,6-diiodo-4-nitroaniline. The polymer structures and properties were characterized by such instrumental methods as NMR $(^1H-,\;^{13}C-,\;and\;^{29}Si-)$, IR, UV-visible spectroscopies and TGA/DSC. The spectral data indicated that the present polymers have the regular alternating structure of 1,1´-bis(ethynyldimethylsilyl)ferrocenylene and arylene units. The resulting polymers were completely soluble in such organic solvents as methylene chloride, chloroform, benzene, chlorobenzene, and THF. The thermal behaviors of the resulting polymers were examined.

• Composites Research
• /
• v.32 no.2
• /
• pp.85-89
• /
• 2019

The size, morphology and composition of nanoparticles are regarded as the most important factors to the efficiency of catalytic reduction of various chemical compounds. In order to make a systematic comparison, gold, platinum and palladium nanoplates with 100 nm diameter with rough surface morphology were manufactured through the galvanic replacement reaction, and the reaction kinetics of the catalytic reduction of 4-nitrophenol and 4-nitroaniline was systematically analyzed by spectroscopic measurement. According to the observation, the catalytic reduction efficiency was significantly different against the constitutional elements in order of Pd > Au > Pt, and it was additionally influenced by the type of substrate.

• Textile Coloration and Finishing
• /
• v.17 no.6 s.85
• /
• pp.1-10
• /
• 2005

Disperse dyes derived from heterocyclic compounds such as phenylindole, pyridone, diaminopyridine, and carbazole have been known to exhibit high light fastness and bathochromic shift compared to the coursponding aminoazobenzene. The synthetic method to obtain diaminopyridine derivatives, which can be used as coupling components, was chlorination of pyridone with phosphorous oxychloride, followed by substitution with various primary amines. Four azo disperse dyes were synthesized by coupling four diaminopyridines with 2-cyano-4-nitroaniline as a diazo component. Structures of these dyes were confirmed by $^1H$ NMR spectroscopy. The wavelengths of maximum absorption of the synthesized disperse dyes were in the range of $517\~528nm$, and molar extinction coefficients were $45,700\~50,100$. The dyeability of four disperse dyes toward PET fiber was generally good. Wash and rubbing fastnesses were excellent, while light and dry heat fastness were good.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.5
• /
• pp.1833-1837
• /
• 2015

An aristolactam-type alkaloid, isolated from Orophea enterocarpa, is enterocarpam-III (10-amino-2,3,4,6-tetramethoxyphenanthrene-1-carboxylic acid lactam). It is cytotoxic to various human and murine cancer cell lines; however, the molecular mechanisms remain unclear. The aims of this study were to investigate cytotoxic effects on and mechanism (s) of human cancer cell death in human hepatocellular carcinoma HepG2 and human invasive breast cancer MDA-MB-231 cells compared to normal murine fibroblast NIH3T3 cells. Cell viability was determined by MTT assay to determine $IC_{10}$, $IC_{20}$ and $IC_{50}$ levels, reactive oxygen species (ROS) production with 2',7'-dichlorohydrofluorescein diacetate and the caspase-3, -8 and -9 activities using specific chromogenic (p-nitroaniline) tetrapeptide substrates, viz., DEVD-NA, IETD-NA and LEHD-NA and employing a microplate reader. Mitochondrial transmembrane potential (MTP) was measured by staining with 3, 3'-dihexyloxacarbocyanine iodide ($DiOC_6$) and using flow cytometry. The compound was cytotoxic to HepG2 and MDA-MB-231 cells with the $IC_{50}$ levels of $26.0{\pm}4.45$ and $51.3{\pm}2.05{\mu}M$, respectively. For murine normal fibroblast NIH3T3 cells, the $IC_{50}$ concentration was $81.3{\pm}10.1{\mu}M$. ROS production was reduced in a dose-response manner in HepG2 cells. The caspase-9 and -3 activities increased in a concentration-dependent manner, whereas caspase-8 activity did not alter, indicating the intrinsic pathway activation. Enterocarpam-III decreased the mitochondrial transmembrane potential (MTP) dose-dependently in HepG2 cells, suggesting that the compound induced HepG2 cell apoptosis via the mitochondrial pathway. In conclusion, enterocarpam-III inhibited HepG2 and MDA-MB-231 cell proliferation and induced human HepG2 cells to undergo apoptosis via the intrinsic (mitochondrial) pathway and induction of caspase-9 activity.

• Archives of Pharmacal Research
• /
• v.25 no.4
• /
• pp.505-510
• /
• 2002

An improved kinetic assay for prekallikrein activator (PKA), a potential vasodilator, has been developed to be used as an indicator for quality control during production of human albumin preparations. It consists of two reaction stages. In the first stage, PKA and prekallikrein are incubated at $37^{\circ}C$ for 45 min to allow the transformation into kallikrein. Kallikrein, a serine protease, catalyzes the splitting of p-nitroaniline (pNA) from its substrate H-D-Pro-Phe-Arg-pNA(S-2302). The rate at which pNA is released was measured spectrophotometrically at 405 nm. Prekallikrein, a substrate of PKA was purified by DEAE ion-exchange chromatography and the major potential variations in the assay were optimized; pH 8.0 and 150 mM sodium chloride were chosen to give a proper ionic strength. Reaction times in the range of 10 to 360 min provided linear dose-response curves. The concentration of prekallikrein was adjusted to fall between 1:1 and 1:3 dilutions to generate a linear standard calibration curve. Under the optimized conditions, reproducibility was checked. In a precision test, the coefficient of variation (CV) stayed within ${\pm}4%$ and the dose-response curve showed a good correlation (${r^2}=0.999$). An accuracy test with an international standard of PKA afforded a mean recovery of 97.5%.