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Chinese Journal of Structural Chemistry 2010年第8期29卷 1189-1196页

作者：荆国华李小林周作明 Department of Environmental Science & Engineering Huaqiao University

With the artificial neural network（ANN） method combined with the multiple linear regression（MLR）,based on a series of quantum chemical descriptors and molecular connectivity indexes,quantitative structure-activity relationship（QSAR） models to predict the acute toxicity（-lgEC50） of substituted aromatic compounds to Photobacterium phosphoreum were *** molecular descriptors that appear in the MLR model,namely,the second order valence molecular connectivity index（2XV）,the energy of the highest occupied molecular orbital（EHOMO）,the logarithm of n-octyl alcohol/water partition coefficient（logKow） and the Connolly molecular area（MA）,were inputs of the ANN *** root-mean-square error（RMSE） of the training and validation sets of the ANN model are 0.1359 and 0.2523,and the correlation coefficient（R） is 0.9810 and 0.8681,*** leave-one-out（LOO） cross validated correlation coefficient（Q L2OO） of the MLR and ANN models is 0.6954 and 0.6708,*** result showed that the two methods are complementary in the *** regression method gave support to the neural network with physical explanation,and the neural network method gave a more accurate model for *** addition,some insights into the structural factors affecting the acute toxicity and toxicity mechanism of substituted aromatic compounds were discussed.

关键词： quantitative structure-activity relationship artificial neural network multiple linear regression acute toxicity substituted aromatic compounds

quantitative structure-activity relationship Study on the Antioxidant activity of Carotenoids

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Chinese Journal of Structural Chemistry 2009年第2期28卷 163-170页

作者：孙玉敬庞杰叶兴乾吕元李俊 College of Biosystem Engineering and Food Science Zhejiang UniversityHangzhou 310029 China College of Food Science Fujian Agriculture and Forestry UniversityFuzhou Fujian 350002 China

Carotenoids are a family of effective active oxygen scavengers, which can reduce the danger of occurrence of chronic diseases such as cardiovascular disease, cataract, cancer, and so on. The quantitative structure-activity relationship （QSAR） equation between carotenoids and antioxidant activity was established by quantum chemistry AM1, molecular mechanism （MM＋） and stepwise regression analysis methods, and the model was evaluated by leave-one-out approach. The results showed that the significant molecular descriptors related to the antioxidant activity of carotenoids were the energy difference （E_HL） between the lowest unoccupied molecular orbital （LUMO） and the highest occupied molecular orbital （HOMO） and ionization energy （Eiso）. The model showed a good predictive ability （Q^2 〉 0.5）.

关键词： quantitative structure-activity relationship antioxidant activity carotenoids

quantitative structure-activity relationship Studies on the Antioxidant activity and Gap Junctional Communication of Carotenoids

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Chinese Journal of Structural Chemistry 2010年第9期29卷 1362-1372页

作者：孙玉敬吴丹刘东红陈健初沈妍叶兴乾 Department of Food Science and Nutrition School of Biosystems Engineering and Food ScienceZhejiang University

The antioxidant and gap junctional communication（GJC） activities of carotenoids are known to be the two main anticancer *** structure-activity relationship（QSAR） models of the two activities were developed using stepwise regression and multilayer perceptron neural network based on the calculated descriptors of quantum *** results showed that the significant molecular descriptor related to the antioxidant activity of carotenoids was the HOMO-LUMO energy gap（EHL） and the molecular descriptor related to the GJC was the lowest unoccupied molecular orbital energy（ELUMO）.The two models of antioxidant activity both showed good predictive power,but the predictive power of the neural network QSAR model of antioxidant activity was *** addition,the two GJC models have similar,moderate predictive *** possible mechanisms of antioxidant activity and GJC of carotenoids were discussed.

关键词： carotenoids antioxidant activity gap junctional communication multilayer perceptron neural network quantitative structure-activity relationship

Toxicity of Selected Imidazolium-based Ionic Liquids on Caenorhabditis elegans： a quantitative structure-activity relationship Study

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Chinese Journal of Chemical Physics 2017年第4期30卷 423-428,I0001页

作者：卢丽亚张颖捷陈洁洁童中华中国科学技术大学化学系中国科学院城市污染物转化重点实验室合肥230026

Due to the large number of ionic liquids （ILs） and their potential environmental risk, assessing the toxicity of ILs by ecotoxicological experiment only is insufficient. quantitative structure- activity relationship （QSAR） has been proven to be a quick and effective method to estimate the viscosity, melting points, and even toxicity of ILs. In this work, the LC50 values of 30 imidazolium-based ILs were determined with Caenorhabditis elegans as a model animal. Four suitable molecular descriptors were selected on the basis of genetic function approximation algorithm to construct a QSAR model with an R^2 value of 0.938. The predicted lgLC50 in this work are in agreement with the experimental values, indicating that the model has good stability and predictive ability. Our study provides a valuable model to predict the potential toxicity of ILs with different sub-structures to the environment and human health.

关键词： Imidazolium-based ionic liquids Caenorhabditis elegans Toxicity quantitative structure-activity relationship

New Descriptors of Amino Acids and Its Applications to Peptide quantitative structure-activity relationship

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Chinese Journal of Structural Chemistry 2008年第11期27卷 1375-1383页

作者：舒茂霍丹群梅虎梁桂兆张梅李志良 College of Bioengineering Chongqing University College of Chemistry and Chemical Engineering Chongqing University Department of Quality Control Chongqing Daxin Pharmaceutical Co. Ltd

A new set of descriptors, HSEHPCSV （component score vector of hydrophobic, steric, and electronic properties together with hydrogen bonding contributions）, were derived from principal component analyses of 95 physicochemical variables of 20 natural amino acids separately according to different kinds of properties described, namely, hydrophobic, steric, and electronic properties as well as hydrogen bonding contributions. HSEHPCSV scales were then employed to express structures of angiotensin-converting enzyme inhibitors, bitter tasting thresholds and bactericidal 18 peptide, and to construct QSAR models based on partial least square （PLS）. The results obtained are as follows： the multiple correlation coefficient （R2cum） of 0.846, 0.917 and 0.993, leave-one-out cross validated Q2cm of 0.835, 0.865 and 0.899, and root-mean-square error for estimated error （RMSEE） of 0.396, 0.187and 0.22, respectively. Satisfactory results showed that, as new amino acid scales, data of HSEHPCSV may be a useful structural expression methodology＇for the studies on peptide QSAR （quantitative structure-activity relationship） due to many advantages such as plentiful structural information, definite physical and chemical meaning and easy interpretation.

关键词： peptide quantitative structure-activity relationship principal component analysis genetic algorithm partial least square

quantitative structure-activity relationships of antimicrobial fatty acids and derivatives against Staphylococcus aureus

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第2期13卷 83-93页

作者： Hui ZHANG Lu ZHANG Li-juan PENG Xiao-wu DONG Di WU Vivian Chi-Hua WU Feng-qin FENG Department of Food Science and Nutrition Zhejiang UniversityHangzhou 310058China ZJU-ENS Joint Laboratory of Medicinal Chemistry College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Food Science and Human Nutrition University of MaineOrono 04469USA

Fatty acids and derivatives(FADs)are resources for natural *** order to screen for additional potent antimicrobial agents,the antimicrobial activities of FADs against Staphylococcus aureus were examined using a microplate *** of fatty acids were the most potent class of fatty acids,among which monotridecanoin possessed the most potent antimicrobial *** conventional quantitative structure-activity relationship(QSAR)and comparative molecular field analysis(CoMFA)were performed to establish two statistically reliable models(conventional QSAR:R2=0.942,Q 2 LOO=0.910;CoMFA:R 2=0.979,Q 2=0.588,respectively).Improved forecasting can be achieved by the combination of these two models that provide a good insight into the structureactivity relationships of the FADs and that may be useful to design new FADs as antimicrobial agents.

关键词： Fatty acid derivatives quantitative structure-activity relationship Comparative molecular field analysis Antimicrobial activity

quantitative prediction of substituted products based on quantum-chemical parameters and neural network method

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Chinese Journal of Chemistry 2000年第4期18卷 521-525页

作者：王学业宋锽 College of Chemistry and Chemical Engineering Xiangtan University Xiangtan Hunan 411105 China

The criterion of orientating group of electrophilic aromatic nitration was discussed by means of pattern recognition method with quantum-chemical parameters as features, and the product ratios of the reactions were quantitatively calculated using artificial neural network (ANN) method with the same parameters as inputs, based on the ab initio calculation of quantum chemistry, The quantum-chemical parameters involved orbital energy, orbital electron population, atomic total electron density and atomic net charge. The predicted values are in agreement with experimental results and the predicted error of the ANN with quantum-chemical parameters for the reaction is the smallest among the all methods.

关键词： Product ratio quantitative structure-activity relationship artificial neural network quantum-chemical parameters

A comparative molecular field analysis of cytotoxic beta-carboline analogs

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Acta Pharmacologica Sinica 2004年第7期25卷 113-119页

作者： Xue-rui HOU, Qi CHEN, Ri-hui CAO, Wen-lie PENG, An-long XU1 Department of Biochemistry and Center for Biopharmaceutical Research, College of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China Department of Biochemistry and Center for Biopharmaceutical Research College of Life Sciences Sun Yat-sen University Guangzhou 510275 China

AIM: To derive a model that could be used in drug design. METHODS: Beta-carbolines are reported to have antitumor activities on cultured cancer cell lines. A comparative molecular field analysis (CoMFA) was undertaken to elucidate the correlation of cytotoxities and structural parameters of 16 beta-carboline analogs (1-16). The compound 12 was finally used as a template for the other compounds in the dataset because of its highest biological activity. RESULTS: The CoMFA applied to the final alignment resulted in a qcv of 0.656 and it showed that the 2 steric fields contributed 43.3 % of the model information while the electrostatic fields represented the other 56.7 %. CONCLUSION: Three designed compounds, which were predicted to have high, moderate and low activities respectively, were synthesized. The IC50 values of these compounds indicated the significance of the analysis in this study. The model derived from the current study could be further used in design for more active compounds.

关键词： beta-carbolines quantitative structure-activity relationship alkaloids

Pharmacophore and Docking-based 3D-QSAR Studies on HIV-1 Integrase Inhibitors

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Chemical Research in Chinese Universities 2014年第2期30卷 297-305页

作者： ZHANG Xiaoyi DENG Dongjie TAN Jianjun HE Yu LI Chunhua WANG Cunxin College of Life Science and Bioengineering Beijing University of Technology Beijing 100124 P.R.China College of Materials Science and Engineering Beijing University of Technology Beijing 100124 P.R.China

Integrase（IN） plays an essential role in the process of HIV-1 *** inhibitors of diketo acid derivatives（DKAs） were analysed by the Comparative Molecular Field Analysis（CoMFA） and Comparative Molecular Similarity Induces Analysis（CoMSIA） methods.A set of 42 compounds were randomly selected as the training set（35） and test set（7）.Firstly,a good pharmacophore（goodness of hit=0.787） was obtained and used to align ***,predictive models were constructed with the CoMFA and CoMSIA methods based on the pharmacophore *** a result,the CoMS1A method yielded the best model with an r2 of 0.955 and a q2 of 0.665,which can predict the activities of the tested DKAs very well（r2=0.559）.Finally,DKAs were docked into IN,and the predicit modes were superimposed on the contour maps obtained from the best CoMSIA *** superimposed maps gave a visualized and meaningful insight into the inhibitory behaviors,providing significantly useful information for the rational drug design of anti-IN agents.

关键词： HIV-1 integrase Diketo acid quantitative structure-activity relationship Pharmacophore Molecular docking

Solvent Effect on Characteristic Vibration of IR Spectrum of 4,4＇-Dibromodiphenyl Ether

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Chemical Research in Chinese Universities 2014年第6期30卷 997-1004页

作者： LI Yu Resources and Environmental Research Academy Key Laboratory of Regional Energy Systems Optimization Ministry of Education North China Electric Power University Beijing 102206 P. R. China

The optimal geometry, IR spectrum and vibration assignment of 4,4＇-dibromodiphenyl ether（BDE-15） in gas phase were calculated via the density functional theory（DFT） at the level of B3LYP/6-3 l＋G（d）. Based on the vi- bration assignment, the calculation of vibration frequencies and intensities of 5 main vibration types of BDE-15 in 25 kinds of solvents was carried out by means of a self-consistent reaction field（SCRF） theoretical model at the level of B3LYP/6-31＋G（d） to analyze the solvent effect on the vibration of IR spectrum of BDE-15. To study the solvent ef- fect further, C--O asymmetric stretching vibration fluctuating, which is relatively acute in both vibration frequency and intensity, was selected as the characteristic vibration to establish different linear solvation energy relation（LSER） models for solvent categoring. Solvent parameters（a, /3, ~r＊）, acceptable number（AN） and quantitative structure- activity relationship（QSAR） models were established via chemical quantum parameters of solvent moleculer, which were first been introduced to investigate different solvent-solute interaction mechanisms in alcoholic and non-alcoholic solvents on molecular level. At last, a single solvent molecule was embedded in the framework of po- larizable continuum model（PCM） to validate the effect of hydrogen bonding on solvent-solute interaction in alcohol solvents. The obtained results show that 5 main vibration types of BDE-15 in different solvents have small variation range in frequency and intensity and all the vibration frequencies in solvents are lower than those in gas phase, de- creasing along with the increasing of the dielectric Constant（e） of solvents exponentially. In contrast, all the vibration intensities in solvents are greater than those in gas phase and present positive exponential trend. Twenty-five solvents were divided into two categories（non-alcoholic solvents and alcoholic solvents） by LSER. The CmO asymmetric stretching vibration was mainly regulated b

关键词： Solvent effect IR spectrum Vibration assignment quantitative structure-activity relationship Hydrogenbonding