• Applied Biological Chemistry
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• 제43권2호
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• pp.95-99
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• 2000

일련의 헤테로 고리 치환(X) chalcone 유도체들에 의한 farnesyl protein transferase(FPTase) 저해활성을 측정하여 분자내 styryl group의 치환기(Y) 변화에 따른 정량적인 구조와 FPTase 저해 활성과의 관계(QSARs)를 modified Free-Wilson(F-W)방법 및 Hansch 방법으로 분석 검토하였다. F-W 분석에 따르면 (X)-치환기는 FPTase 저해 활성에 기여하지 않았다 그러나 (Y)-치환기들은 ortho>meta>para 치환체의 순서로 ortho-치환체와 ${\alpha}$탄소의 알짜 전하$(C_{\alpha})$가 활성에 기여하였다. 모든 헤테로 고리 치환체에 대한 Hansch 분석에 의하면 전자 밀게(R<0)의 폭$(B_1)$이 작은 ortho-치환체로서 적정값, $(R)_{opt.}=-0.35$를 갖는 공명상수가 저해활성에 영향을 미친다는 사실을 알 수 있었다. 그리고 헤테로 치환체들 사이의 FPTase 저해활성은 모두 비례관계를 보임으로써 같은 경향으로 저해활성이 발현되었으며 비(H)치환체 45가 제일 높은 FPTase 저해활성$(pI_{50}=4.30)$을 보였다.

• Natural Product Sciences
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• 제19권1호
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• pp.8-14
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• 2013

The inhibitory effect and the structure-activity relationships of luteolin and its related derivatives isolated from Taraxacum mongolicum against MAO activities were investigated. The activity-guided isolation of extract from Taraxacum mongolicum led to the isolation of three flavonoids, luteolin, diosmetin, and luteolin-7-glucoside, a polyphenol, chlorogenic acid, a tyrosine and a uridine. The inhibitory activities of luteolin and its related derivatives against MAOs activities are dependent on their molecular structures. The presence of the phenolic hydroxy group at para-position is the active site for MAO-A inhibition as well as of MAO-B. The methoxy group has no potential on MAO-A inhibition. An additional phenolic hydroxy group at the ortho-position alleviates about 4-fold MAO-A inhibitory activity of phenolic hydroxy group at para-position. A carboxylic group seems to be critical for DBH inhibition and has no effects on MAO.

• 상하수도학회지
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• 제9권2호
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• pp.127-135
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• 1995

The purpose of this study was to more fully evaluate the potential for chlorophenol degradation in anaerobic sludge. The pH effects on the ring cleavage of phenol and dechlorination of monochlorophenol isomers and dichlorophenl isomers. This study results are as follows ; Each of the monochlorophenol isomers were degraded in anaerobic sludge. The relatives rates were 2-Chlorophenol > 3-Chlorophenol > 4-Chlorophenol. Biodegradation results for the dichlorophenol isomers in anaerobic sludge are such as 2,3-dichlorophenol and 2,5-dichlorophenol was reductively dechlorinated to 3-chlorophenol, 2,4-dichlorophenol to 4-chlorophenol, 2,6-dichlorophenol to 2-chlorophenol. The two dichlorophenol isomers which did not contain an ortho Cl substituent 3,4-dichlorophenol and 3,5-dichlorophenol were persistent during the 6-week incubation. The rate of dechlorination was enhanced by the presence of a Cl group ortho, rather than para, to the site of dechlorination.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1647-1652
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• 2012

With the objective to design and synthesis of Schiff's base symmetrical liquid crystal dimmers and to study the effect of molecular structure variation ($o-ortho$, $m-meta$, $p-para$) and change in alkoxy terminal chain length on mesomorphic properties of liquid crystals, We have synthesized Schiff base dimers from dialdehyde derivative containing 2-hydroxy-1,3-dioxypropylene as short spacer with aniline derivatives having different lengths of terminal alkoxy chains ($n$ = 5, 7, 9). The chemical structure of the final products was characterized by proton nuclear magnetic resonance ($^1H$ NMR) spectroscopy and fourier transform infrared (FT-IR) spectroscopy. The mesomorphic properties and optical textures of the resultant dimers were characterized by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The existence of smectic A phase transition was confirmed by the observation of batonnets and fan shaped textures in optical microscopy when compound were heated from crystalline phase. All of the dimers of this series, with the exception of $\mathbf{2S_5}$ -ortho, -meta, -para, were thermotropic liquid crystal. The compound $\mathbf{2S_9}$ -meta was monotropic, while the rest were enantiotropic. It was found that the change in terminal alkoxy chain length has pronounced effect on the mesomorphic properties. The temperature range of smectic A phase window widens with increasing alkoxy chain length.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.257-260
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• 2001

유기용매 내성 균주를 분리하기 위해서 석유화학 공업단지 부근의 폐수 및 토양을 채취하여 각종 유기용매에 적응시킨 후 순수 분리를 통하여 내성을 가진 균주를 분리하였으며 그 중에 서 가장 내성이 강한 균주 BCND 106, 154 and 171 을 분리하였다. 이 균주를 이용하여 유기용매 내성 및 분해능 검사를 하였다. 그 결과 이 세 균주는 본 실험에 사용한 유기용매 대부분에 대해서 내성을 나타내었으며, 또한 이를 탄소원으로도 이용하였다. 특히 BCNU 106 과 171 은 xylene isomer 인 meta-, para-xylene을 탄소원으로 이용할 뿐아니라 특히 독성이 강한 것으로 알려져 있는 ortho-xylene도 동시에 분해하는 것으로 알 수 있었다. 또한 항생제와 중금속에 대해서도 강한 내성을 나타내었는데, 이는 유기용매 내성 기작과 밀집한 관련이 있는 것으로 판단한다.

• Bulletin of the Korean Chemical Society
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• 제23권2호
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• pp.337-345
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• 2002

The equilibrium structures for the ground and transition states of $C_7H_7^+$ isomers have been investigated using sophisticated ab initio quantum mechanical techniques with various basis sets. The structures of tropyrium and benzyl cations have been fully optimized at the DZP CCSD(T) levels of theory. And the structures of o-, m-and p-tolyl cations are optimized fully up to the DZ CCSD(T) levels of theory. The geometries for the transition states between three isomers of tolyl cations have been optimized up to DZP CISD level of theory. The SCF harmonic vibrational frequencies for tropylium, benzyl, and three isomers of tolyl cations are all real numbers, which confirm the potential minima and each unique imaginary vibrational frequencies for TS1 and TS2 confirm the true transition states. The relative energy of the benzyl cation with respect to the tropyrium cation is predicted to be 28.5 kJ/mol and is in good agreement with the previous theoretical predictions. The 0 K heats of formation, ${\Delta}H^{\circ}_{f0}$, have been predicted to be 890, 1095, 1101, and 1110 kJ/mol for tropylium, ortho-, meta-, and para-tolyl cations by taking the experimental value of 919 kJ/mol for the benzyl cation as the base level. The relative stability between tolyl cations is in the order of ortho

• 대한화학회지
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• 제25권1호
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• pp.38-43
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• 1981

L-Glutamic acid와 aniline 誘導體로부터 다음과 같은 새로운 pyrrolidone-anilide誘導體를 合成했다. 이 化合物들의 構造가 元素分析, UV, IR, NMR 그리고 Mass 스펙트럼으로 (R)-2-pyrrolidone-5-carbox-p-chloroanilide, (R)-2-pyrrolidone-5-carbox-o-toluidide, (R)-2-pyrrolidone-5-carbox-m-toluidide, (R)-2-pyrrolidone-5-carbox-p-toluidide임이 확인되었다. 이 化合物들의 무우, 벼 種子發芽와 生育에 대한 phytotoxicity을 調査한 結果는 다음과 같다. 이 化合物들은 벼 種子에 대하여 發芽 및 發根抑制?果를 나타내었다. 그 중에서 (R)-2-pyrrolidone-5-carboxanilide와 (R)-2-pyrrolidone-5-carbox-p-chloroanilide 誘導體는 무우 種子의 發芽와 生育을 현저하게 抑制하였다. 또한 (R)-2-pyrrolidone-5-carboxtoluidide 誘導體에 있어서 methyl group의 結合位置 (ortho, meta, para)에 따라서 무우의 生育抑制率이 다르다는 것을 알았다. 즉 (R)-2-pyrrolidone-5-carbox-m-toluidide는 (R)-2-pyrrolidone-5-carbox-o-toluidide와 (R)-2-pyrrolidone-5-carbox-p-toluidide 보다 무우 種子의 生育阻害現象이 현저하였다.

• 약학회지
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• 제54권5호
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• pp.328-333
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• 2010

Comparative molecular field analyses (CoMFA) on the antiproliferative activity of N-substituted (R) 2-amino-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole analogues (ADTs: 1-17) against bladder cancer (HCV29T) and rectal cancer (SW707) cells were studied quantitatively. The statistical predictability and fitness of CoMFA A1 model for bladder cancer cells were better than those of CoMFA F1 model for rectal cancer cells and the antiproliferative activity of ADTs depends on steric field (HCV29T: 93.1% & SW707: 83.8%). Also, from the contour maps of optimized CoMFA models, the activity for bladder cancer cells had predicted to increase when sterically favored groups were substituted on meta- and para-position, and sterically disfavored groups were substituted on one ortho-position of phenyl ring. The activity for rectal cancer cells had predicted to increase when sterically favored groups were substituted on para-position, and sterically disfavored groups were substituted on two ortho-position of phenyl ring as R-group.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.548-552
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• 2005

The interaction between ionic surfactants and different nonionic molecules and polymers are studied using ion surfactant selective electrode. From the experimental data, critical concentrations of the interaction and binding process are evaluated. The interaction between hexadecyltrimethylammonium bromide (HTAB) with polyethylene glycol (PEG) in three molecular weights (1000, 10000 and 100000) and also schiff-bases, 2-[2-carboxyphenyl nitrilomethylidyne]-phenol (ortho CNP), 2-[3-carboxyphenyl nitrilomethylidyne]-phenol (meta CNP)and 2-[4-carboxyphenyl nitrilomethylidyne]-phenol (para CNP) with the potentiometric method were investigated using HTAB membrane selective electrode. In the case of PEG with increasing molecular weights more interaction to HTAB occurs. The electromotive force (EMF) data also showed that interaction between para CNP with HTAB is more than the other schiff-bases. It seems this case related to less space interference of COOH group for that compound. The onset of binding ($T_1$) of course is the same for three schiffbase molecules.

• Journal of Pharmaceutical Investigation
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• 제41권4호
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• pp.233-238
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• 2011

DEET, N,N'-diethyl-m-toluamide, is the most commonly used mosquito repellent. However, it can easily permeate through skin leading to toxic effects. A recent study showed that the ortho analogue of DEET showed enhanced repellency with reduced permeation compared to the commercially used meta analogue. Thus, in order to understand the differences in properties and effectiveness among the m-, o- and p-analogues of DEET, an HPLC-UV method was developed for separately analyzing the three analogues. Moreover, stability profiles at temperatures ranging from $30^{\circ}C$ to $70^{\circ}C$ as well as pH ranging from pH 3 to pH 9 have been determined. All three analogues were stable with no degradation observed during the 5 day period. o-DEET therefore could be further developed into a safer and more effective mosquito repellent.