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Prediction of Infinite Dilution Activity Coefficients of Alcohol and Ether Organic Compounds in Water

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Chinese Journal of Structural Chemistry 2010年第12期29卷 1808-1813页

作者：王维许惠英 Zhenhai Environmental Monitoring Station college of biology & Environment engineering Zhejiang Shuren University

Based on QSPR of alcohol and ether organic compounds in water,geometrical optimization and electrostatic potential calculations were performed at the HF/6-31G＊ level for 73 alcohol and ether organic *** relationships between infinite dilution activity coef-ficient（lnγ∞） of alcohols and ethers in water and theoretical descriptors of the molecular structure were established by multiple regression *** result shows that the parameters derived from molecular electrostatic potential together with molecular surface area can be preferably used to express the quantitative structure-lnγ∞ relationship of alcohols and ethers in *** reveals that this model has good predictive capabilities（RCV=0.969）.The molecular electrostatic potential has also been proved to have the general applicability in QSPR model of alcohol and ether organic compounds about γ∞ in *** QSPR model established may provide a new powerful method for predicting γ∞ of organic compounds in aqueous systems.

关键词： alcohol and ether organic compounds infinite dilution activity coefficient(γ∞) molecular electrostatic potential QSPR

Optimization of Extraction of Antioxidants from Turmeric(Curcuma longa L.) Using Response Surface Methodology

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Wuhan university Journal of Natural Sciences 2018年第1期23卷 63-69页

作者： LIU Caiqin CHEN Weiqing WANG Nan JIN Jianchang college of biology and Environment engineering Zhejiang Shuren University

Turmeric is a spice widely used to enhance the taste and color of certain meats. We investigated the antioxidant capacities of turmeric ethanol soaking extracts by utilizing the scavenging properties of hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl（DPPH） free radical. The results showed that the optimum extraction parameters were： extraction time 4 h, sample-solvent ratio 1：84.12, solvent 72.34% ethanol solution, and water bath temperature 81.3 ℃. The optimum ethanol soaking extraction parameters were： extraction time 4 h, sample-solvent ratio 1：90.74, solvent 80.46% ethanol solution, water bath temperature 88.2 ℃. With these parameters, the hydroxyl radical scavenging rate and the DPPH free radical clearance of crude extracts from turmeric can reach about 93.78% and 40.69%, respectively. These results indicate that ethanol soaking extraction may be a useful method for extracting antioxidants from turmeric.

关键词： turmeric ethanol soaking extraction antioxidantactivity hydroxyl radical scavenging capacity 1,1-diphenyl-2-picrylhydrazyl(DPPH)scavenging capacity

QSPR Analysis of the Physicochemical Properties for Phthalic Acid Esters

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1880-1884页

作者： XU Hui-Ying SHU Tian-Ge WANG Wei ZHU Jian-Qing LU Yin XU Xiao-Lu WU Gang college of biology & Environment engineering Zhejiang Shuren University Zhenhai Environmental Monitoring Station Department of Basic Courses Zhejiang Shuren University Shaoxing university

Based on quantitative structure-property relationship （QSPR） of organic compounds, the molecular connectivity indices of 21 phthalic acid ester compounds were extracted. Relationship between the physicochemical properties （n-octanol/air partition coefficient, vapor pressure, water solubility） and the molecular connectivity indices of phthalic acid ester compounds have been established by multiple linear regression （MLR） method. The results showed that the zero-order valence connectivity index （0Xu） is the topology parameter which affects octanol/water partition coefficient and water solubility, and the topology parameter which affects vapor pressure is the first-order connectivity index （1X）. This indicated to a certain extent_that the molecular connectivity indices can be well used to express the quantitative relationship between the physicochemical properties and structure descriptions of phthalic acid ester compounds. The models constructed have good robustness and highly predictive capability.

关键词： phthalic acid esters molecular connectivity index,physicochemical property QSPR

Synthesis, Crystal Structure and Fungicidal Activity of 3-(Difluoromethyl)-1-methyl-N-((2-(trifluoromethyl)phenyl) carbamoyl)-1H-pyrazole-4-carboxamide

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Chinese Journal of Structural Chemistry 2019年第5期38卷 706-712,668页

作者： SUN Na-Bo ZHAI Zhi-Wen TONG Jian-Ying CAI Peng-Peng HE Fang-Yue HAN Liang LIU Xing-Hai college of biology and Environmental engineering Zhejiang Shuren University Hangzhou 310015 China college of Chemical engineering Zhejiang University of Technology Hangzhou 310014 China

The title compound 3-（difluoromethyl）-1-methyl-N-（（2-（trifluoromethyl）phenyl）-carbamoyl）-1 H-pyrazole-4-carboxamide(C14 H11 F5 N4 O2) was synthesized, and its structure was confirmed by 1 H NMR, H RMS and X-ray diffraction. It crystallizes in monoclinic system, space group P21/n with a = 6.994（3）, b = 13.860（6）, c = 15.308（7） ?, β = 97.632（6）°, V = 1470.8（11） ?3,Z = 4, the final R = 0.0692 and wR = 0.2108 for 3989 observed reflections with Ⅰ > 2σ（Ⅰ）. The preliminary biological test shows that the title compound has moderate fungicidal activities against Pseudomonas syringae.

关键词： pyrazole acyl urea synthesis crystal structure fungicidal activities

Molecular Recognition of Pyromellitic Imide-azacyclophane to Organic Pollutant

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Chinese Journal of Structural Chemistry 2012年第4期31卷 591-598页

作者：许惠英王维徐向阳 college of biology&Environment engineering Zhejiang Shuren University Zhenhai Environmental Monitoring Station

Anion can be identified by pyromellitic imide-azacyclophane which is one of the host *** article investigated the interaction between the host and organic pollution *** host and other eight compounds were optimized by DFT（density functional theory） B3LYP/6-31G level and the energy of compounds was corrected using Boys-Bemardi *** the basis of B3LYP/6-31G optimized geometries,the RDG function and sign（λ2（r））ρ（r） function values of space points were calculated,and color RDG isosurface map was drawn.3He chemical shift was calculated by the B3LYP/6-31G *** results showed that the eight organic pollution molecules with the host one shaped stable configurations by hydrogen bonds,*** stabilization energy of complexes 4 and 7 showed repulsion（steric effects） of cyclophane cage observably affecting the stability of the *** location,intensity and the type of interaction in complex 1 were analyzed through color-filled RDG isosurface *** calculations showed that the weak interaction reduced the transverse induction ring current in the host rings,and deteriorated the aromaticity of compounds.

关键词： cyclophane RDG isosurface map molecular recognition aromaticity

Investigation of the Substituent Effects on π-Type Pnicogen Bond Interaction

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Chinese Journal of Structural Chemistry 2018年第3期37卷 356-366页

作者：许惠英曹生炜王维朱建清邹建卫许晓路陆胤 college of biology & Environment engineering Zhejiang Shuren University zhejiang Linix Motor CO. LTD zhejiang Surveying Institute of Estuary and Coast Department of Basic Courses Zhejiang Shuren University Ningbo Institute of Technology Zhejiang University

Intermolecular interactions between PH2Cl and Ar–R（R = H,OH,NH2,CH3,Br,Cl,F,CN,NO2） were calculated by using MP2/aug-cc-p VDZ quantum chemical *** has been shown from our calculations that the aromatic rings with electron-withdrawing groups represent much weaker binding affinities than those with electron-donating *** charge-transfer interaction between PH2Cl and Ar–R plays an important role in the formation of pnicogen bond complexes,as revealed by NBO ***,AIM analysis shows that the nature of the interactions between PH2Cl and Ar–R is electrostatic,and the interaction energies of the complexes are correlated positively with the electron densities in the bond critical points（BCPs）.RDG/ELF graphical analyses were performed to visualize the positions and strengths of the pnicogen bonding,as well as the spatial change of the electron localization upon the formation of *** π-type halogen bond was also calculated,and it has been revealed that the π-type pnicogen bond systems are more stable than the halogen bond ones.

关键词： π-type pnicogen bonding π-type halogen bonding NBO AIM RDG/ELF analysis

Theoretical Study on Enol-keto Tautomerism of α-Fluorine-β-diketones

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Chinese Journal of Structural Chemistry 2006年第3期25卷 363-367页

作者：王艳花俞庆森邹建卫卢运祥许惠英 college of biology and Environment engineering Zhejiang Shuren University Key Laboratory for Molecular Design and Nutrition engineering.of Ningbo City Ningbo Institute of Technology Zhejiang University

Density Functional Theory method is applied to investigate the enol-keto tautomerism of both acyclic and cyclic α-fluorine-β-diketones. It is shown that, for acyclic cases, α-fluorine could improve the relative stability of keto tautomer by lessening intramolecular hydrogen bond of enol form, whereas the relative stability of cyclic enol could be attributed to two factors： destabilization of keto and stabilization of enol. Furthermore, the relative stabilities of all enol tautomers are improved in THF to different extents.

关键词： density functional theory α-fluorine-β-diketones tautomers

QSPR Studies on the Physicochemical Properties of Polychlorinated Diphenyl Sulfides——The Application of Theoretical Descriptors Derived from Electrostatic Potentials on Molecular Surface

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Chinese Journal of Structural Chemistry 2015年第7期34卷 995-1003页

作者：王维许惠英周侣艳唐东跃 zhejiang Surveying Institute of Estuary and Coast college of biology & Environment engineering Zhejiang Shuren University Hangzhou Environmental Monitoring Station

Based on the relationship between the quantitative structure and property（QSPR） of organic compounds, the surface electrostatic potential parameters of 29 polychlorinated diphenyl sulfides（PCDPSs） with experimental values were calculated and extracted, and Multiple Linear Regression（MLR） was used to model the linear relationship between the physicochemical properties（octanol/water partition coefficient, high performance liquid chromatography capacity factor） and molecular structure parameters of PCDPSs. The result shows that the main factors that affect the n-octanol/water partition coefficient and high performance liquid chromatography capacity factor are respectively the number of chlorin atoms substituted on the benzene ring（NCl） and the lowest unoccupied molecular orbital energy（ELUMO）. Secondly, there are also molecular surface electrostatic potentials. This indicates that the molecular surface electrostatic potentials can effectively express the quantitative relationship between the physicochemical properties of PCDPSs and their molecule descriptions. The QSPR models established have strong stability and predictive ability. This also has proved the applicability of molecular surface electrostatic potential parameters in QSPR of PCDPSs.

关键词： polychlorinated diphenyl sulfides(PCDPSs) molecular electrostatic potential physicochemical property QSPR

A QSRR Study on the Relative Retention Time of Halogenated Methyl-phenyl Ethers

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Chinese Journal of Structural Chemistry 2006年第7期25卷 811-817页

作者： XU Hui-Ying YU Qing-Sen ZOU Jian-Wei WANG Yan-Hua WANG Hong-Qing CHEN Xue-Song college of biology ＆ Environment engineering Zhejiang Shuren University Hangzhou 310015 China Key Laboratory for Molecular Design and Nutrition engineering Ningbo Institute of Technology Zhejiang University Ningbo 315104 China

Halogenated methyl-phenyl ethers （anisoles） are ubiquitous organic compounds in the environment. In the present study, geometrical optimization and electrostatic potential calculations have been performed for 42 halogenated anisoles at the HF/6-31 G^＊ level. A number of statistically based parameters have been obtained. By multiple regression method, linear relationships between the gas-chromatographic relative retention time （RRT） and structural descriptors have been established for the training set of 32 halogenated anisoles. The result showed that the parameters derived from electrostatic potentials （ESPs） together with the molecular volume （Vmc） could be well used to express the quantitative structure-RRT relationships of halogenated anisoles. The best two-variable regression model gives a correlation coefficient of 0.980 and a standard deviation of 0.07, and the leave-one-out cross-validated correlation coefficient is 0.975. The goodness of the model has been further validated through exploring the predictive power for the testing set of 10 halogenated anisoles.

关键词： halogenated methyl-phenyl ethers (anisoles) molecular electrostatic potentials (ESPs) relative retention time (RRT) QSRR