• 대한화장품학회지
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• 제36권3호
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• pp.199-205
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• 2010

기질 화합물로써 일련의 phenyl-2,2'-methylenebis(cyclohexane-1,3-dione) 유도체(1-22)들의 치환기($R_1$ 및 $R_2$)가 변화함에 따른 tyrosinase 활성저해에 대한 분자 홀로그래피적인 정량적 구조-활성관계(HQSAR) 모델을 유도하였다. 그리고 tyrosinase 저해활성에 미치는 구조상 요소들의 분석결과에 근거하여 높은 tyrosinase 저해활성을 보이는 새로운 tyrosinase 저해활성 분자를 설계하였다. 또한, 통계적으로 양호한 E-2 모델(상관성; $r_2$ = 0.929 및 예측성; $q_2$ = 0.564)을 유도하였으며 설계된 화합물, P1 ($Pred.pI_{50}$ = 5.48)는 기준물질로 사용된 kojic acid에 비하여 약 13.4배 높은 저해활성을 나타낼 것으로 예측되었다.

• 대한토목학회논문집
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• 제11권3호
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• pp.11-18
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• 1991

휘발성 유기물질(VOC)은 많은 경로를 통해 발생되는데, 독성이 있을뿐 아니라 발암물질을 포함하고 있으므로, 이들 물질 제거는 매우 중요하다. 본 연구에서는 휘발성 유기물질 처리를 위해 활성탄을 사용할 경우 처리와 설계를 위해 흡착능력의 연구가 반드시 필요하다. 그러므로, 본 연구에서는 사용할 화합물에 대한 가스 상태의 등온흡착선을 물리적 특성과 액화상태의 등온흡착선으로 부터 예측하였다. 이를 위해 이용된 방법이 quantitative structure-activity relationships(QSAR) 방법이다. 가스 상태의 등온흡착선을 분자연결제수($^2{\chi}$)와 헨리의 계수, 또는 용해도와 가스 상태의 평형농도에 의해서 예측 할 수 있었다. 연구결과, Freundlich 모델을 근거로한 가스 상태의 등온흡착선은 ${\log}\;a_g=0.238\;^2{\chi}+0.573\;{\log}\;H_a+4.330(r^2=0.94)$ 이었다. 결과적으로, 저흡착능력 범위에서 Freundlich 이론을 근거로한 이 방법은 시간소비적 실험을 통하지 않고도 가스 상태의 등온흡착선을 예측할 수 있다는 것을 제시하고 있다.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4397-4402
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• 2011

The NF-${\kappa}B$ system of transcription factors plays a crucial role in inflammatory diseases, making it an important drug target. We combined quantitative structure activity relationships for predicting the activity of new compounds and quantitative dynamic models for the NF-${\kappa}B$ network with intracellular concentration models. GFA-MLR QSAR analysis was employed to determine the optimal QSAR equation. To validate the predictability of the $IKK{\beta}$ QSAR model for an external set of inhibitors, a set of ordinary differential equations and mass action kinetics were used for modeling the NF-${\kappa}B$ dynamic system. The reaction parameters were obtained from previously reported research. In the IKKb QSAR model, good cross-validated $q^2$ (0.782) and conventional $r^2$ (0.808) values demonstrated the correlation between the descriptors and each of their activities and reliably predicted the $IKK{\beta}$ activities. Using a developed simulation model of the NF-${\kappa}B$ signaling pathway, we demonstrated differences in $I{\kappa}B$ mRNA expression between normal and different inhibitory states. When the inhibition efficiency increased, inhibitor 1 (PS-1145) led to long-term oscillations. The combined computational modeling and NF-${\kappa}B$ dynamic simulations can be used to understand the inhibition mechanisms and thereby result in the design of mechanism-based inhibitors.

• 농업과학연구
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• 제35권1호
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• pp.33-40
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• 2008

The structural characteristics that influence on the fungicidal activities of N-phenylbenzenesulfonamide (1~24) and N-phenyltheinylsulfonamide (25~30) derivatives against Dampping-off (Pythium ultimum) were discussed quantitatively using the models of molecular holographic quantitative structure-activity relationships (HQSAR). From the based on these findings, the statistical results of the optimized HQSAR F-3 model showed better predictablity ($r^2_{cv.}$ or $q^2=0.581$) and correlation coefficient ($r^2_{ncv.}=0.963$). And, from the analytical results of the atomic contribution maps on the fungicidal activities, the most active compound is $R_1=2-fluoro-4-chloro$ substituent (4) and the most inactive one is $R_1=4-methoxy$ substituent (20). It was found that the 2-fluoro-4-chlorophenyl group as a $R_1$-group was an important structure and a characteristic factor not only for herbicidal activity but also for fungicidal activity.

• Applied Biological Chemistry
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• 제34권3호
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• pp.287-294
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• 1991

Benzotriazole 유도체들의 정량적인 구조와 발아후 벼(Oryzae sativa L) 및 피(Echinochloa crus-galli)에 대한 생장저해 활성값$(pI_{50})$사이의 관계들이 QSAR 방법으로 연구되었다. QSAR 분석에 의하면, 자유 라디칼 파라미터$(E_R)$가 매우 중요한 요소이었으며 $pI_{50}$ 값은 파라치환기(X)의 $E_R$ 파라미터에 대하여 포물선형의 관계를 나타내었다. (3)의 생장저해 활성은 (4)보다 우세하였으며 생장저해 활성이 가장 큰 화합물은 (3b)이었고 피의 생장저해 활성에 대한 $E_R$ 파라미터의 적정값은 각각 $E_R(3)=0.52$와 $E_R(4)=0.15$이었다. 분자설계 결과, 치환기(X)가 전자 끌게이고 적정값 (0.52)의 $E_R$ 파라미터를 가지는 분자가 가장 활성이 클 것으로 기대되었으며 Benzotriazole 유도체들의 생장저해 활성은 광합성반응(PS-II)에서 전자전달을 효과적으로 차단하는 결과로 믿어진다.

• Bulletin of the Korean Chemical Society
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• 제17권2호
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• pp.147-152
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• 1996

To see the quantitative relationship between the structures of the C-7 substituted quinolones and their antibacterial activities, theoretical parameters such as the molecular van der Waals volume, surface area and some electrostatic parameters based on the molecular electrostatic potential, which represent lipophilicity, and some quantum mechanical parameters are introduced as descriptors. The sixteen substituted quinolone derivatives and twenty bacteria are used for the study. It is found that the QSARs of C-7 substituted quinolones are obtained for eleven bacteria and our descriptors are more useful for Gram positive organisms than negative ones. It is also shown that molecular surface area (or molecular Waals volume) of the C-7 substituent and net charge of C-7 atom of the quinolones are the descriptors of utmost importance.

• 농약과학회지
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• 제14권3호
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• pp.191-198
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• 2010

새로운 고활성의 살충성 화합물을 예측하고 설계하기 위하여 N'-phenyl-N-methylformamidine 유도체들의 두점박이 응애(Tetranychus urticae)에 대한 살충활성과 물리-화합적인 설명인자들 사이의 2차원적인 정량적 구조-활성관계(2D-QSAR)와 분자 홀로그래피적인 정량적 구조-활성관계(HQSAR)를 구체적으로 검토하였다. 2D-QSAR 모델(1 및 3)로부터 입체적인 요소로서 $R_3$-치환기의 폭($B_2$)과 $R_4$-치환기의 적정한 전체 쌍극자능율값(TDM=2.025 D)이 살충활성에 주로 영향을 미쳤으며 살충활성은 $R_3$- 및 $R_4$-치환기들에 의존적이었다. 특히, 2D-QSAR 모델(3)과 HQSAR 모델 F2에 의하여 설계된 새로운 유력한 활성화합물(P1; $EC_{50}$=0.516 ppm)의 살충활성은 Amitraz에 비하여 약 34.3배 높을 것으로 예측되었다.

• 약학회지
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• 제55권2호
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• pp.91-97
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• 2011

To search a new anti-depressant agents against para-chloroamphetamine-induced excitation, three dimensional quantitative-structure relationships (3D-QSAR) models between structure of 3a,4-dihydro-3H-[1]-benzopyronao[4,3]isoxazoles (1-30) and thieir inhibitory activity against para-chloroamphetamine-induced excitation were performed and discussed quantitatively using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods. From these basis on the findings, the optimized CoMSIA-2F model ($q^2$=0.793 and $r^2$=0.952) showed the best statistical results. And also, it is found that the para-chloroamphetamine inhibitory activity from the optimized CoMSIA-2F model was dependent on steric field (35.2%) and electrostatic field (64.8%) of tricyclic isoxazoles. Particularly, it is predicted that the inhibitory activity against para-chloroamphetamine-induced excitation will be able to increase by the designed compounds from the CoMSIA-2F model.

• 한국환경성돌연변이발암원학회지
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• 제20권1호
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• pp.21-25
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• 2000

Recently there is increasing interest in the use of structure activity relationships for predicting the biological activity of chemicals. The reasons for the interest include the decrease cost and time per chemical as compared with animal or cell system for identifying toxicological effects of chemicals and the reduction in the use of animals for toxicological testing. This study is to test the validity of the mutagenicity data generated from QSAR (Quantitative Structure Activity Relationship) program. Thirty chemicals, which had been evaluated by Ames test during 1997-1999, were assessed with TOPKAT QSAR mutagenicity prediction module. Among 30chemicals experimented, 28 were negative and 2 were positive for Ames test. On the contrary, 23 chemicals showed the high confidence level indicating high prediction rate in mutagenicity evaluation, and 7 chemicals showed the lsow to moderate confidence level indicating low prediction in mutagenicity evaluation. Overall mutagenicity prediction rate was 77% (23/30). The prediction rates for non-mutagenic chemicals were 79% (22/28) and mutagenic chemicals were 50% (1/2). QSAR could be a useful tool in providing toxicological data for newly introduced chemicals or in furnishing data for MSDS or in determining the dose in toxicity testing for chemicals with no known toxicological data.

• 한국환경성돌연변이발암원학회지
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• 제21권2호
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• pp.118-121
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• 2001

The predictive screening of various molecular descriptors for predicting carcinogenic, mutagenic, teratogenic and alkylation activity of chlorinated disinfection byproducts (DBPs) has been investigated for the application of quantitative structure-activity relationships (QSAR). The toxicity index for 29 compounds were computed by the PASS program and active values were employed in this study. Studies show that different descriptors account for the model equation of each genotoxic endpoint and that thermodynamic descriptors significantly played a major role on prediction of endpoints of chlorinated aliphatic compounds.