• 제목/요약/키워드: QSAR analysis

검색결과 148건 처리시간 0.021초

토마토 역병균 항균 활성 데이터의 이분번 근사모델링 (Two Class Approximation of TLB (Tomato Late Blight) Activity Data)

  • 한호규;;조승주
    • 농약과학회지
    • /
    • 제9권2호
    • /
    • pp.140-145
    • /
    • 2005
  • 정량적 구조 활성관계 모델링은 물리적인 성질과 생물학적 활성이 관계 있다는 것을 전제로 한다. 그러나, 퍼센트 활성과 같은 데이터들은 모델링에 많이 활용되지 않았다. 이것의 중요한 이유중의 하나는 이러한 값들이 정량적이 아니고 정성적인 데에 있다. 본 연구에서는 분자모델링에 퍼센트활성 데이터를 활용하기 위하여 데이터 값들을 2개의 계층으로 분류하고 CoMFA(비교분자장)를 판별함수로 활용하였다. 즉, 베타-케토아세트아닐라이드 유도체들의 토마토 역병균에 대한 항균력 시험의 퍼센트 활성 데이터를, 한 계층은 활성이 있는 것, 다른 계층은 활성이 없는 것으로 나누었다. 특히, CoMFA를 활용함으로써 화학적인 이해에 중요한 3차원적인 정보를 얻을 수 있었다. 이 모델은 주어진 데이타를 98%의 정확도로 설명하였으며, LOO 검증을 해본 결과 예측력은 약 69% 정도였다 이 결과는 활성 데이터를 근사적으로 2개의 계급으로 나누고 CoMFA를 활용하는 방식이 구조활성관계를 이해하고 화합물 유도체를 합성하는데 활용될 수 있음을 보여준다.

잿빛곰팡이병균(Botrytis cinerea)에 대한 N-Phenyl-O-phenyl-thionocarbamate 유도체들의 살균활성에 관한 3D-QSAR 분석 (3D-QSAR Analysis on the Fungicidal Activity of N-phenyl-O-phenylthionocarbamate Analogues against Gray Mold (Botrytis cinerea))

  • 성낙도;박기한;장석찬;성민규
    • 농약과학회지
    • /
    • 제11권2호
    • /
    • pp.59-66
    • /
    • 2007
  • 감수성(SBC) 및 저항성(RBC) 잿빛곰팡이병균(Botrytis cinerea)에 대한 N-phenyl-O-phenylthionocarbamate 유도체들의 살균활성에 대한 3차원적인 구조와 활성과의 관계(3D-QSAR)를 CoMFA와 CoMSIA 방법으로 검토하였다. 최적화 된 CoMFA 모델의 예측성과 상관성이 CoMSIA 모델보다 양호하였으며 ($r^2$$q^2=CoMFA{\gg}CoMSIA$) SBC 균주에 대한 살균활성 모델이 RBC에 대한 모델보다 양호한 통계값 ($r^2=SBC{\gg}RBC$)을 나타내었다. 또한, CoMFA 모델에서는 정전기장보다 입체장이 큰 영향을 미쳤다. CoMSIA 모델에서는 RBC 및 SBC에 대한 살균활성에 관한 CoMSIA장의 영향은 서로 상이하였으나 수소결합 주게장의 영향은 같았다. 통계적으로 양호한 CoMFA 모델에 의하여 두 균주사이 살균활성에 관한 선택성 요소는 입체장의 차이에 기인하는 것으로 판단된다. 그러므로 N-phenyl 고리상 meta 및 para-치환체의 큰 입체장은 SBC에 대한 살균활성을 향상시킬 것으로 예측되었다.

3D QSAR Study on Pyrrolopyrimidines-Based Derivatives as LIM2 Kinase Inhibitors

  • Balasubramanian, Pavithra K.;Balupuri, Anand;Cho, Seung Joo
    • 통합자연과학논문집
    • /
    • 제8권4호
    • /
    • pp.285-292
    • /
    • 2015
  • LIM kinases belong to the serine/Threonine kinase family. The members of the LIM kinase (LIMK) family include LIMK 1 and 2 which are involved in the regulation of actin polymerisation and microtubule disassembly. LIMK1 was shown to be involved in cancer metastasis, while LIMK2 activation promotes cells cycle progression. Since LIMK2 plays a vital role in many disease conditions such as pulmonary hypertension, cancer and viral diseases, and till date there are not much selective inhibitors been reported, LIMK2 becomes an interesting therapeutic target among the kinases. 3D QSAR study was carried out on a series of pyrrolopyrimidines based derivatives as LIMK2 inhibitors. A reasonable CoMFA ($q^2$=0.888; ONC=3; $r^2$=0.974) with good statistical values was developed. The developed model was validated using 1000 runs of boostrapping and was found to be predictable. The results of CoMFA contour map analysis suggested that the bulky substitution at $R_4$ and $R_5$ position are highly desirable to increase the activity. Similarly, positive substitution at $R_3$ position is also required to increase the activity. It is also noted that bulky substitution at $R_1$ position must be avoided. Our results could provide valuable information to enhance the activity of the LIMK2 inhibitors and to design potent pyrrolopyrimidines derivatives.

새로운 3-Benzylidenemyosmine 유도체와 Nicotin Acetylcholine 수용체 사이의 결합 친화력 상수에 관한 HQSAR 분석과 분자설계 (Molecular Holographic QSAR Analysis on the Bonding Affinity Constants between Nicotin Acetylcholine Receptors and New 3-Benzylidenemyosmine Analogues and Molecular Design)

  • 장석찬;성낙도
    • Applied Biological Chemistry
    • /
    • 제50권2호
    • /
    • pp.127-131
    • /
    • 2007
  • 일련의 새로운 3-benzylidenemyosmine 유도체들의 구조 변화와 미국 바퀴벌래(Periplaneta. americana L.)의 nicotin acetylcholine 수용체 (nAChRs) 사이의 결합 친화력 상수에 관한 정량적인 구조와 활성과의 관계를 분자 홀로그램(H) QSAR 방법으로 검토하였다. 친화력 상수에 관하여 가장 양호한 HQSAR 모델은 분자조각 크기 5${\sim}$8 bin 조건에서 유도된 모델(IV-2)이었다. HQSAR 모델(VI-2)은 높은 예측성(q$^2$=0.507)과 상관성(r$^2_{nev.}$=0.944)에 근거하여 양호한 통계값들을 나타내었다. 그리고 HQSAR 기여도로부터 결합 친화력 상수는 분자내 anabaseine 고리에 의존적이었으며 결합 친화력성이 높은 화합물들이 최적화된 모델(VI-2)에 의하여 설계되었다.

Comparative Molecular Field Analysis of Caspase-3 Inhibitors

  • Sathya, B.;Madhavan, Thirumurthy
    • 통합자연과학논문집
    • /
    • 제7권3호
    • /
    • pp.166-172
    • /
    • 2014
  • Caspases, a family of cysteinyl aspartate-specific proteases plays a central role in the regulation and the execution of apoptotic cell death. Activation of caspases-3 stimulates a signaling pathway that ultimately leads to the death of the cell. Hence, caspase-3 has been proven to be an effective target for reducing the amount of cellular and tissue damage. In this work, comparative molecular field analysis (CoMFA) was performed on a series of 3, 4-dihydropyrimidoindolones derivatives which are inhibitors of caspase-3. The best predictions were obtained for CoMFA model ($q^2=0.676$, $r^2=0.990$). The predictive ability of test set ($r^2_{pred}$) was 0.688. Statistical parameters from the generated QSAR models indicated the data is well fitted and have high predictive ability. Our theoretical results could be useful to design novel and more potent caspase-3 derivatives.

Comparative Molecular Field Analysis of CXCR-2 Inhibitors

  • Sathya., B
    • 통합자연과학논문집
    • /
    • 제9권2호
    • /
    • pp.121-127
    • /
    • 2016
  • CXC chemokine receptor 2 (CXCR2) is a prominent chemokine receptor on neutrophils. The neutrophilic inflammation in the lung diseases is found to be largely regulated through CXCR2 receptor. Antagonist of CXCR2 may reduce the neutrophil chemotaxis and alter the inflammatory response. Hence, in the present study, ligand based Comparative molecular field analysis (CoMFA) was performed on a series of CXCR2 antagonist named pyrimidine-5-carbonitrile-6-alkyl derivatives. The optimum CoMFA model was obtained with statistically significant cross-validated coefficients ($q^2$) of 0.568 and conventional coefficients ($r^2$) of 0.975. The contour maps suggest the important structural modifications and this study can be used to guide the development of potent CXCR2 antagonist.

Hologram Based QSAR Analysis of Xanthine Oxidase Inhibitors

  • Sathya., B
    • 통합자연과학논문집
    • /
    • 제10권4호
    • /
    • pp.202-208
    • /
    • 2017
  • Xanthine Oxidase is an enzyme, which oxidizes hypoxanthine to xanthine, and xanthine to uric acid. It is widely distributed throughout various organs including the liver, gut, lungs, kidney, heart, brain and plasma. It is involved in gout pathogenesis. Hence, in the present study, Hologram based Quantitative Structure Activity Relationship Study was performed on a series of Xanthine Oxidase antagonist named 2-(indol-5-yl) thiazole derivatives. The best HQSAR model was obtained using Atoms, Bonds, Connection, Hydrogen, Chirality and Donor Acceptor as fragment distinction parameter using hologram length 71 and 4 components with fragment size of minimum 2 and maximum 5. Significant cross-validated correlation coefficient ($q^2$= 0.563) and non cross-validated correlation coefficients ($r^2$= 0.967) were obtained. The model was then used to evaluate the six external test compounds and its $r^2{_{pred}}$ was found to be 0.798. Contribution map show that presence of propyl ring in indole thiazole makes big contributions for improving the biological activities of the compounds. We hope that our HQSAR model and analysis will be helpful for future design of xanthine oxidase antagonists.

Fragment based QSAR Analysis of CXCR-2 Inhibitors Using Topomer CoMFA Approach

  • Thirumurthy, M
    • 통합자연과학논문집
    • /
    • 제10권4호
    • /
    • pp.209-215
    • /
    • 2017
  • CXC chemokine receptor 2 (CXCR2) is a prominent chemokine receptor on neutrophils. CXCR2 antagonist may reduce the neutrophil chemotaxis and alter the inflammatory response because the neutrophilic inflammation in the lung diseases is found to be largely regulated through CXCR2 receptor. Hence, in the present study, Topomer based Comparative Molecular Field Analysis (Topomer CoMFA) was performed on a series of CXCR2 antagonist named pyrimidine-5-carbonitrile-6-alkyl derivatives. The best Topomer COMFA model was obtained with significant cross-validated correlation coefficient ($q^2$ = 0.487) and non cross-validated correlation coefficients ($r^2$ = 0.980). The model was evaluated with six external test compounds and its $r^2{_{pred}}$ was found to be 0.616. The steric and electrostatic contribution map show that presence of bulkier and electropositive group around cyclopropyl ring may contribute more for improving the biological activities of these compounds. The generated Topomer CoMFA model could be helpful for future design of novel and structurally related CXCR2 antagonists.

Comparative Molecular Similarity Indices Analysis (CoMSIA) of 8-substituted-2-aryl-5-alkylaminoquinolines as Corticotropin-releasing factor-1 Receptor Antagonists

  • Nagarajan, Santhosh Kumar;Madhavan, Thirumurthy
    • 통합자연과학논문집
    • /
    • 제9권4호
    • /
    • pp.241-248
    • /
    • 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.

Comparative Molecular Similarity Indices Analysis of Caspase-3 Inhibitors

  • Babu, Sathya;Madhavan, Thirumurthy
    • 통합자연과학논문집
    • /
    • 제7권4호
    • /
    • pp.227-233
    • /
    • 2014
  • Caspases, a family of cysteinyl aspartate-specific proteases plays a central role in the regulation and the execution of apoptotic cell death. Activation of caspases-3 stimulates a signaling pathway that ultimately leads to the death of the cell. Hence, caspase-3 has been proven to be an effective target for reducing the amount of cellular and tissue damage. In this work, comparative molecular similarity indices analysis (CoMSIA) was performed on a series of 3,4-dihydropyrimidoindolones derivatives which are inhibitors of caspase-3. The best predictions were obtained for CoMSIA model ($q^2$ = 0.586, $r^2$ = 0.955). The predictive ability of test set ($r^2_{pred}$) was 0.723. Statistical parameters from the generated QSAR models indicated the data is well fitted and have high predictive ability. Our theoretical results could be useful to design novel and more potent caspase-3 derivatives.