• 통합자연과학논문집
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• 제9권4호
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• pp.241-248
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• 2016

Corticotropin-releasing factor receptors (CRFRs) activate the hypothalamic-pituitary-adrenal axis, which is an integral part of the fight or flight response to stress. Increase in CRH level is observed in Alzheimer's disease and major depression and hypoglycemia. Here, we report on the relevant physicochemical parameters required for the CRFR inhibitors. Comparative molecular similarity indices analysis (CoMSIA) was performed with the derivatives of 8-substituted-2-aryl-5-alkylaminoquinolinesas CRFR inhibitors. The best predictions were obtained for the best CoMSIA model with a $q^2$ of 0.576 with 6 components and $r^2$ of 0.977. The statistical parameters from the generated CoMSIA models indicated that the data are well fitted and have high predictive ability. CoMSIA contour maps could be useful in the designing of more potent and novel CRFR derivatives.

• 통합자연과학논문집
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• 제4권2호
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• pp.99-102
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• 2011

Effect of protonation and deprotonation of ionization compounds is an important application in Comparative molecular field analysis (CoMFA). There are enough information's were reported about different CoMFA applications such as Series design and selection of training set, Geometries and optimizations of molecules, Effect of partial atomic charges, bioactive conformations and alignment, Interaction energy fields, Effects of different grid spacing etc. However limited information's are available about the ionization of compounds. This study aimed at the critical review of about the effects of protonation of ionizable molecules and its impact on the predictability of CoMFA models. We also discussed about previous implications and the things needed to be considered to come for a final conclusion about its impact on CoMFA predictability.

• Bulletin of the Korean Chemical Society
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• 제28권2호
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• pp.211-219
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• 2007

The subtle but significant differences and thereby the lack of consensus in active site structures among the crystal structures of cyclin-dependent kinase 2 (CDK2) has hampered structure-based drug design. In this study, we devised a simple but effective ‘mutation, pharmacophore-guided docking, followed by mutation' strategy to generate an “average” CDK2 structure, which was used for ligand docking study to successfully reproduce 30 out of 32 X-ray ligand positions within 2.0 A of heavy atom RMSD. This novel docking method was applied for structure-based 3D QSAR with CoMSIA study of a series of structurally related ligands, which showed a good discrimination between CDK2 binders and nonbinders.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.65.2-65.2
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• 2003

88 selective COX-2 inhibitors belonging to three chemical classes (triaryl rings, diaryl cycloalkanopyrazoles, and diphenyl hydrazides) were studied using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). Partial least squares analysis produced statistically significant models with q values of 0.84 and 0.79 for CoMFA and CoMSIA, respectively. The key spatial properties were detected by careful analysis of the isocontour maps. The binding energies calculated from flexible docking correlated with inhibitory activities by the least-squares fit method. (omitted)

• 농약과학회지
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• 제11권3호
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• pp.131-137
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• 2007

상이한 정렬조건에서 imidaclopid 유도체 중, imidazol 고리상 N-치환체(X)들의 벼멸구(Nilaparvata lugens)에 대한 살충활성에 관하여 CoMFA 및 CoMSIA 모델을 유도하고 정량적으로 검토하였다. 두 최적 모델의 예측성($q^2$ 또는 $r_{cv.}^2$)과 상관성($r_{ncv.}^2$)은 field fit (FF) 정렬보다 atom based fit (AF) 정렬조건의 모델이 좋았으며 CoMFA (A5) 모델보다 CoMSIA (A10) 모델이 더 좋았다. 최적의 CoMSIA (A10) 모델로부터 N-치환체(X)들에 의한 살충활성은 주로 정전기장과 수소결합 받게장에 의존적이었다. 그러므로 CoMSIA (A10) 모델의 등고도로부터 benzoyl 고리(X)상 ortho- 위치에는 양전하, carbonyl기의 산소원자 부분에는 음전하가 큰 작용기일수록 그리고 ortho- 및 meta- 위치의 수소결합 받게가 살충활성을 개선하는데 크게 기여할 것으로 예측되었다.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.733-740
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• 2003

To find a new substance with superior melanogenesis inhibitory activity, the bioactivities of alkyl-3,4-dihydroxy-5-substituted benzoate (A) and N-alkyl-3,4-dihydroxy-5-substituted benzamide (B) derivatives as substrate of tyrosinase were measured in mouse melanoma cells. And the bioactivities analyzed using comparative molecular similarity indices analysis (CoMSIA). From the CoMSIA model, when cross-validation value (q$^2$) is 0.713 at four components, the pearson correlation coefficient ($r^2$) is 0.900. Unknown compounds were predicted, using QSAR analyzed results from the CoMSIA methods. Excellent agreement was obtained between the measured and the predicted bioactivities of unknown compounds. As the results of prediction from CoMSIA, we could conclude that the bioactivities were increased from pl$_{50}$=3.18-4.80 to above 5.17 by creation of 6-methylheptyl, n-pentylphenyl and 2-hydroxypentylphenyl group etc,.,.

• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.613-617
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• 2009

3D-QSARs for the inhibition activities against protox by herbicidal 2-N-phenylisoindolin-1-one derivatives were studied quantitatively using CoMFA and CoMSIA methods. The result of the statistical quality of optimized CoMSIA model 2 ($FF:\;{r^2}_{cv.};\;0.973\;&\;{r^2}_{ncv.};\;0.612$) was higher than that of CoMFA model 1 ($AF:\;{r^2}_{cv.};\;0.414\;&\;{r^2}_{ncv.};\;0.909$). Also, the relative contribution of the optimized CoMSIA model 2 showed the steric (24.6%), electrostatic (31.0%), hydrophobic (ClogP, 23.4%) and H-bond acceptor field (21.0%), respectively. From the results of the contour maps, the protox inhibition activities are expected to increase when steric favor and H-bond acceptor favor groups are substituted on $R_2$ position and positive favor group are substituted on $C_2,\;C_3,\;and\;C_5$ atom in phenyl ring of $R_2$ position. And the inhibition activities are expected to increase when hydrophobic favor group is substituted on $C_1,\;C_3$ atom in phenyl ring of $R_2$ position and $C_1$ atom of $R_2$ position and hydrophilic favor groups are substituted on $C_4$ atom in phenyl ring of $R_1$ position and the terminal group of $R_1$ position.

• 농약과학회지
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• 제11권3호
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• pp.138-143
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• 2007

감수성(SBC) 및 저항성(RBC) 잿빛곰팡이병균(Botrytis cinerea)에 대한 N-phenyl-O-phenylthionocarbamate 유도체들의 선택적인 살균활성에 대한 3차원적인 구조와 활성과의 관계(3D-QSAR)를 CoMFA와 CoMSIA 방법으로 검토하였다 그 결과, 통계적으로 CoMFA 모델(M5)보다 CoMSIA 모델(M7)이 양호하였으며 살균활성의 선택성에 미치는 요소는 CoMSIA 모델(M7)의 정전기장에 의존적이었다. 그러므로 CoMSIA 모델(M7)의 등고도로부터 N-phenyl 고리의 meta-위치에 음하전을 띄는 수소결합 주게에 의하여 선택성이 개선될 것으로 예상되었다.

• 통합자연과학논문집
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• 제9권3호
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• pp.190-198
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• 2016

Xanthine Oxidase is an enzyme, which oxidizes hypoxanthine to xanthine, and xanthine to uric acid. It is widely distributed throughout various organsincluding the liver, gut, lung, kidney, heart, brain and plasma. It is involved in gout pathogenesis. In this study, we have performed Comparative Molecular Field Analysis (CoMSIA) on a series of 2-(indol-5-yl) thiazole derivatives as xanthine oxidase (XO) inhibitors to identify the structural variations with their inhibitory activities. Ligand based CoMSIA models were generated based on atom-by-atom matching alignment. In atom-by-atom matching, the bioactive conformation of highly active molecule 11 was generated using systematic search. Compounds were aligned using the bioactive conformation and it is used for model generation. Different CoMSIA models were generated using different alignments and the best model yielded across-validated $q^2$ of 0.698 with five components and non-cross-validated correlation coefficient ($r^2$) of 0.992 with Fisher value as 236.431, and an estimated standard error of 0.068. The predictive ability of the best CoMSIA models was found to be $r{^2}_{pred}$ 0.653. The study revealed the important structural features required for the biological activity of the inhibitors and could provide useful for the designing of novel and potent drugs for the inhibition of Xanthine oxidase.

• Applied Biological Chemistry
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• 제36권5호
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• pp.381-386
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• 1993

새로운 25종의 Imazethapyr 유도체, (2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-3-(N-methyl-N-(X)치환-phenylaminooxoacetyl)-5-methylpyridine)들을 합성하여 치환기(X) 변화에 따른 발아 전 후, 피(Echinochla crus-galli.)의 제초활성에 미치는 3-(N-mothy-N-(X)치환-phenylaminoozoacetyl) group의 영향을 검토한 바, 발아 전보다 발아 후의 제초활성에 더 큰 영향을 미침을 알 수 있었다. 발아 후의 제초활성은 X-치환기의 전자밀게 효과와 입체상수 $(E_s)$에 의존적이었으며 가장 큰 제초활성을 나타내는 화합물로는 $bulky(E_s<0)$하고 전자밀게$(\sigma<0)$가 치환된 화합물, 15(4-t-butyl group)와 20(3,5-dimethyl group)이었다. 그리고 높은 제초활성을 나타낼 것으로 예상되는 화합물의 조건들이 검토되었다.