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Elucidating the structure-activity relationship of Cu-Ag bimetallic catalysts for electrochemical CO_(2) reduction
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作者 Qining Huang Lili Wan +1 位作者 Qingxuan Ren Jingshan Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期345-351,I0009,共8页
Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential fo... Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst design.Herein,we prepared two Cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of Cu nanowires.When tested in a flow cell,the Cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the top.The catalysts were further studied in the H-cell and zero-gap MEA cell.It was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic catalysts.Our work elucidates the structure-activity relationship of bimetallic catalysts for CO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity. 展开更多
关键词 Electrochemical CO_(2)reduction Bimetallic catalyst CU-AG structure-activity relationship
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Structure-activity Relationships of the Coloration and Stability of Anthocyanidins 被引量:1
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作者 翁晨 赵昶灵 王崇德 《Agricultural Science & Technology》 CAS 2014年第4期526-532,共7页
Taking the six common anthocyanidins in nature, i.e. cyanidin, delphinidin, malvidin, pelargonidin, peonidin and petunidin, as examples, this paper summarized the main achievements about the structure-activity relatio... Taking the six common anthocyanidins in nature, i.e. cyanidin, delphinidin, malvidin, pelargonidin, peonidin and petunidin, as examples, this paper summarized the main achievements about the structure-activity relationships of the coloration and stability of anthocyanidins. The coloration and stability of anthocyanidins are funda- mentally determined by the chemical and spatial structures of the anthocyanidins. The electron-deficient state, hydroxylation and methylation patterns, especially the ones on the B-ring, and coplanarity of the three rings of anthocyanidins are inde- pendently or synergetically, positively and/or negatively, influence the coloration and stability of the anthocyanidins. Thereinto, the in vivo colorations of anthocyanins are also related to the organ-selective and crystal- or anthocyanic vacuolar inclusion- related existence of the anthocyanidins. This review could provide a reference for the researches of the structure-optimizing and function-exploiting of anthocyanidins and also for the selection of the crops and cultivars containing specific anthocyani- din profiles. 展开更多
关键词 structure-activity relationship ANTHOCYANIDINS COLORATION STABILITY
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Review on mechanisms and structure-activity relationship of hypoglycemic effects of polysaccharides from natural resources 被引量:5
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作者 Xiaolong Ji Jianhang Guo +3 位作者 Tengzheng Cao Tingting Zhang Yanqi Liu Yizhe Yan 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期1969-1980,共12页
Diabetes mellitus(DM)is a common multifactorial disease,causing various complications,such as chronic metabolism.The current therapies for diabetes mellitus are commercial diabetic drugs that have different definite s... Diabetes mellitus(DM)is a common multifactorial disease,causing various complications,such as chronic metabolism.The current therapies for diabetes mellitus are commercial diabetic drugs that have different definite side effect.However,polysaccharides mainly extracted from natural resources,have advantages of safety,accessibility,and anti-diabetic potential.We have summarized recent research of natural polysaccharides with hypoglycemic activities,focusing on different pharmacological mechanisms in various cell and animal models.The relationships of structure-hypoglycemic effect are also discussed in detail.This review could provide a comprehensive perspective for better understanding on development and mechanism of natural polysaccharides against diabetes mellitus,which have been required by clinical studies yet. 展开更多
关键词 POLYSACCHARIDES Hypoglycemic effect MECHANISMS structure-activity relationship
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Studies on the Synthesis, Anticonvulsant Activity, and the Structure-Activity Relationships of Phenyl Pyridazinones and their GABA Derivatives
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作者 徐萍 王书玉 刘维勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 1992年第2期27-34,共8页
In searching for effective anticonvulsant agents,fourteen 6-aryl-4.5-di- hydro-3(2H)pyridazinones.fifteen 6-aryl-3(2H)pyridazinones,and seventeen 3-GABA derivatives of 6-aryIpyridazines have been synthesized,and evalu... In searching for effective anticonvulsant agents,fourteen 6-aryl-4.5-di- hydro-3(2H)pyridazinones.fifteen 6-aryl-3(2H)pyridazinones,and seventeen 3-GABA derivatives of 6-aryIpyridazines have been synthesized,and evaluated in mice for the ability to antagonize maximal electroshock seizure(MES).The ED_(50) values showed that 6-(2′,4′- dichlorophenyt)-3(2H)pyridazinone was the most potent anticonvulsant among these corn- pounds(ED_(50)=10.15 mg/kg).The structure-activity relationships of the aryl pyridazinones were studied.The result showed that:(1)the higher the value of the hydrophobic parameter л of the substituent on the phenyl ring.the more potent the anticonvulsant activity of the corn- pound.and(2)only the compounds with an electron withdrawing substituent on the phenyl ring exhibited appreciable anticonvulsant activity. 展开更多
关键词 Aryl pyridazinones 3-GABA-6-aryl pyridazines Anticonvulsant activity structure-activity relationships
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Advances in Research of Biological Activity,Action Mechanism and Structure-Activity Relationship of Lentinan
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作者 Jiawen LI Chao ZHAO +2 位作者 Xiaojian GONG Huaguo CHEN Xin ZHOU 《Asian Agricultural Research》 2023年第12期28-38,共11页
Lentinula edodes is the second largest edible mushroom in the world and is widely used as food and medicine.Modern research shows that lentinan(LNT)is the main active component of L.edodes.It has anti-cancer,treatment... Lentinula edodes is the second largest edible mushroom in the world and is widely used as food and medicine.Modern research shows that lentinan(LNT)is the main active component of L.edodes.It has anti-cancer,treatment of diabetes,intestinal protection,anti-inflammatory,anti-oxidation,anti-aging,hepatoprotective,immune-regulating effects.In this review,the biological activity,action mechanism and structure-activity relationship of LNT in recent years are reviewed.On this basis,the existing problems were discussed,and the future research and application of LNT were prospected.Finally,it is hoped that this review will promote the in-depth study of LNT and provide a reference for its development as a drug and functional food. 展开更多
关键词 LENTINAN BIOLOGICAL ACTIVITIES Action mechanism structure-activity relationship
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Structure-activity Relationships of Vasorelaxing Effect of Polyarginine Oligopeptides
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作者 顾鸣镝 彭师奇 +6 位作者 郭雪清 蒋秀荣 蔡孟深 董淑云 张力 张越 唐朝枢 《Journal of Chinese Pharmaceutical Sciences》 CAS 1992年第2期35-41,共7页
Based on the EDRF(endothelium derived relaxing factor)-like effects for polyarginine Arg-Arg-oH was selected as the lead compound and its derivatives Arg-Arg- OCH_3.Arg Arg-Arg-OH,HO-ArgCOCH_2CH_2COArg-OH,HO-ArgCOCH_2... Based on the EDRF(endothelium derived relaxing factor)-like effects for polyarginine Arg-Arg-oH was selected as the lead compound and its derivatives Arg-Arg- OCH_3.Arg Arg-Arg-OH,HO-ArgCOCH_2CH_2COArg-OH,HO-ArgCOCH_2COArg-OH,were synthesized.These substances showed on bioassay various degrees of vasorelaxant activities. With protection for the C-terminal of Arg-Arg-OH with a methyl ester.the vasorelaxing ac- tivitv was decreased.In contrast.when the N-terminal of Arg-OH was protected with mal- onic acid or butane diacid.the biological activites were lower than those of Arg-Arg-OH due to the lowered metabolic rate.With protection of N-terminal of Arg-Arg-OH with L-Arg residue.Arg-Arg-Arg-OH was obtained,which showed a vasorelaxing activity better than that of Arg-Arg-OH.The bioactivities observed on the Wister's rats for the former com- pound become the experimental basis for prodrug design of EDRF. 展开更多
关键词 Polyarginine oligopeptide structure-activity relationships Endothelium derived relaxing factor (EDRF)-like activties
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Determination of structure-activity relationships between fentanyl analogs and human μ-opioid receptors based on active binding site models 被引量:3
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作者 Ming Liu Xiaoli Liu +2 位作者 Ping Wan Qiangsan Wu Wenxiang Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第4期267-276,共10页
Fentanyl is a potent and widely used clinical narcotic analgesic, as well as a highly selective IJ-opioid agonist. The present study established a homologous model of the human μ-opioid receptor; an intercomparison o... Fentanyl is a potent and widely used clinical narcotic analgesic, as well as a highly selective IJ-opioid agonist. The present study established a homologous model of the human μ-opioid receptor; an intercomparison of three types of μ-opioid receptor protein sequence homologous rates was made. The secondary receptor structure was predicted, the model reliability was assessed and verified using the Ramachandran plot and ProTab analysis. The predictive ability of the CoMFA model was further validated using an external test set. Using the Surflex-Dock program, a series of fentanyl analog molecules were docked to the receptor, the calculation results from Biopolymer/SitelD showed that the receptor had a deep binding area situated in the extracellular side of the transmembrane domains (TM) among TM3, TM5, TM6, and TMT. Results suggested that there might be 5 active areas in the receptor. The important residues were Asp147, Tyr148, and Tyr149 in TM3, Trp293, and His297 in TM6, and Trp318, His319, Ile322, and Tyr326 in TM7, which were located at the 5 active areas. The best fentanyl docking orientation position was the piperidine ring, which was nearly perpendicular to the membrane surface in the 7 TM domains. Molecular dynamic simulations were applied to evaluate potential relationships between ligand conformation and fentanyl substitution. 展开更多
关键词 μ-opioid receptor fentanyl analogs AGONIST active site structure-activity relationship
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A Systematic Review of Uric Acid Transporter 1(URAT1) Inhibitors for the Treatment of Hyperuricemia and Gout and an Insight into the Structure-activity Relationship(SAR) 被引量:1
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作者 蔡文卿 刘巍 +2 位作者 刘长鹰 王建武 赵桂龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第6期897-910,共14页
Gout is caused by the deposition of uric acid as monosodium urate(MSU). Chronic hyperuricemia is the necessary condition for MSU deposition, which arises from over-production and/or under-excretion of uric acid. Ren... Gout is caused by the deposition of uric acid as monosodium urate(MSU). Chronic hyperuricemia is the necessary condition for MSU deposition, which arises from over-production and/or under-excretion of uric acid. Renal under-excretion of uric acid accounts for greater than 90% of the patients with hyperuricemia, making URAT1 inhibitors, which act through uricosuric effect a promising class of urate-lowering therapy(ULT). This review aims at the summary and discussion of the latest development of URAT1 inhibitors for the treatment of hyperuricemia and gout and providing an insight into their structure-activity relationship(SAR), which will be helpful to the design of URAT1 inhibitors for both academic research and pharmaceutical industry. The current development pipeline of URAT1 inhibitors is promising and encouraging. 展开更多
关键词 GOUT HYPERURICEMIA urate-lowering therapy uricosuric URAT1 inhibitor structure-activity relationship sar
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Quantitative Structure-activity Relationship(QSAR) Study of Toxicity of Substituted Aromatic Compounds to Photobacterium Phosphoreum 被引量:2
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作者 荆国华 李小林 周作明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第8期1189-1196,共8页
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... 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 established.Four 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 model.The 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,respectively.The leave-one-out(LOO) cross validated correlation coefficient(Q L2OO) of the MLR and ANN models is 0.6954 and 0.6708,respectively.The result showed that the two methods are complementary in the calculations.The regression method gave support to the neural network with physical explanation,and the neural network method gave a more accurate model for QSAR.In addition,some insights into the structural factors affecting the acute toxicity and toxicity mechanism of substituted aromatic compounds were discussed. 展开更多
关键词 quantitative structure-activity relationship artificial neural network multiple linear regression acute toxicity substituted aromatic compounds
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Application of PCA and HCA to the Structure-activity Relationship(SAR) Study of Fluoroquinolones 被引量:1
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作者 LI Xiao-Hong ZHANG Rui-Zhou +1 位作者 CHENG Xin-Lu YANG Xiang-Dong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第11期1351-1358,共8页
Density functional theory (DFT) was used to calculate a set of molecular descri ptors (properties) for 14 fluoroquinolones with anti-B.fragilis activity. Principal component analysis (PCA) and hierarchical clust... Density functional theory (DFT) was used to calculate a set of molecular descri ptors (properties) for 14 fluoroquinolones with anti-B.fragilis activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed in order to reduce dimensionality and investigate which subset of variables should be more effective for classifying fluoroquinolones according to their an-B.fragilis activity degree. The PCA shows that the variables of ELUMO, AEHL, μ, Q2, Q3, Q5, Q6, QB, LogP, MR and MP are responsible for the separation between compounds with higher and lower anti-B.fragilis activities. The HCA results are similar to those obtained with PCA. By using the chemometric results, 4 synthetic compounds were analyzed through PCA and HCA, and 2 of them are proposed as active molecules against B.fragilis, which is consistent with the results of clinic experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with anti-B.fragilis activity. 展开更多
关键词 structure-activity relationship DFT PCA HCA
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A Structure-activity Relationship (SAR) Study of Fluoroquinolones with Biological Activity against Anti-S.pneumoniae
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作者 李小红 张瑞州 +1 位作者 程新路 杨向东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第1期33-40,共8页
Structure-activity relationship techniques were employed to classify fluoroquinolones against S.pneumoniae. Density functional theory (DFT) was used to calculate a set of molecular descriptors (properties) for eig... Structure-activity relationship techniques were employed to classify fluoroquinolones against S.pneumoniae. Density functional theory (DFT) was used to calculate a set of molecular descriptors (properties) for eighteen fluoroquinolones. The descriptors were further analyzed using the principal component analysis (PCA), hierarchical cluster analysis (HCA) and K-nearest neighbor (KNN) chemometeric method. The PCA and HCA methods are quite efficient to classify the eighteen compounds into two groups (active and inactive) according to their degrees of anti- S.pneumoniae activity. The classified result is consistent with the clinic experimental result. The PCA shows that the variables Q3 (net charge on atom 3), QA (net charge on ring A), QB (net charge on ring B), VOL (molecular volume) and A (surface area) are found to be responsible for the separation between compounds with higher and lower anti-S.pneumoniae. 展开更多
关键词 structure-activity relationship DFT PCA HCA KNN
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Development and structure-activity relationships of tanshinones as selective 11β-hydroxysteroid dehydrogenase 1 inhibitors
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作者 Xu Deng Su-Ling Huang +6 位作者 Jian Ren Zheng-Hong Pan Yu Shen Hao-Feng Zhou Zhi-Li Zuo Ying Leng Qin-Shi Zhao 《Natural Products and Bioprospecting》 2022年第1期573-585,共13页
11β-Hydroxysteroid dehydrogenase 1(11β-HSD1)represents a promising drug target for metabolic syndrome,includ-ing obesity and type 2 diabetes.Our initial screen of a collection of natural products from Danshen led to... 11β-Hydroxysteroid dehydrogenase 1(11β-HSD1)represents a promising drug target for metabolic syndrome,includ-ing obesity and type 2 diabetes.Our initial screen of a collection of natural products from Danshen led to the identi-fication of tanshinones as the potent and selective 11β-HSD1 inhibitors.To improve the druggability and explore the structure-activity relationships(SARs),more than 40 derivatives have been designed and synthesized using tanshinone IIA and cryptotanshinone as the starting materials.More than 10 derivatives exhibited potent in vitro 11β-HSD1 inhibitory activity and good selectivity over 11β-HSD2 across human and mouse species.Based on the biological results,SARs were further discussed,which was also partially rationalized by a molecular docking model of 1 bound to the 11β-HSD1.Remarkably,compounds 1,17 and 30 significantly inhibited 11β-HSD1 in 3T3-L1 adipocyte and in livers of ob/ob mice,which merits further investigations as anti-diabetic agents.This study not only provides a series of novel selective 11β-HSD1 inhibitors with promising therapeutic potentials in metabolic syndromes,but also expands the boundaries of the chemical and biological spaces of tanshinones. 展开更多
关键词 Metabolic syndrome TANSHINONES Selective 11β-HSD1 inhibitors structure-activity relationships
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Some substrates of P-glycoprotein targeting <i>β</i>-amyloid clearance by quantitative structure-activity relationship (QSAR)/membrane-interaction (MI)-QSAR analysis
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作者 Tongyang Zhu Jie Chen Jie Yang 《Advances in Bioscience and Biotechnology》 2013年第9期872-895,共24页
The pathogenesis of Alzheimer’s disease (AD) putatively involves a compromised blood-brain barrier (BBB). In particular, the importance of brain-to-blood transport of brain-derived metabolites across the BBB has gain... The pathogenesis of Alzheimer’s disease (AD) putatively involves a compromised blood-brain barrier (BBB). In particular, the importance of brain-to-blood transport of brain-derived metabolites across the BBB has gained increasing attention as a potential mechanism in the pathogenesis of neurodegenerative disorders such as AD, which is characterized by the aberrant polymerization and accumulation of specific misfolded proteins, particularly β-amyloid (Aβ), a neuropathological hallmark of AD. P-glycoprotein (P-gp), a major component of the BBB, plays a role in the etiology of AD through Aβ clearance from the brain. Our QSAR models on a series of purine-type and propafenone-type substrates of P-gp showed that the interaction between P-gp and its modulators depended on Molar Refractivity, LogP, and Shape Attribute of drugs it transports. Meanwhile, another model on BBB partitioning of some compounds revealed that BBB partitioning relied upon the polar surface area, LogP, Balaban Index, the strength of a molecule combined with the membrane-water complex, and the changeability of the structure of a solute-membrane-water complex. The predictive model on BBB partitioning contributes to the discovery of some molecules through BBB as potential AD therapeutic drugs. Moreover, the interaction model of P-gp and modulators for treatment of multidrug resistance (MDR) indicates the discovery of some molecules to increase Aβ clearance from the brain and reduce Aβ brain accumulation by regulating BBB P-gp in the early stages of AD. The mechanism provides a new insight into the therapeutic strategy for AD. 展开更多
关键词 P-Glycoproteins Quantitative structure-activity relationship ATP-BINDING Cassette Transporters MULTIDRUG Resistance Blood-Brain Barrier
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Structure-activity relationships regarding the antioxidant effects of the flavonoids on human erythrocytes
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作者 Yousif Y. Bilto Sanaa Suboh +1 位作者 Talal Aburjai Shtywy Abdalla 《Natural Science》 2012年第9期740-747,共8页
The effects of eleven flavonoids on lipid peroxidation, protein degradation, deformability and osmotic fragility of human erythrocytes exposed in vitro to 10 mM H2O2 for 60 min at 37 oC have been studied. The followin... The effects of eleven flavonoids on lipid peroxidation, protein degradation, deformability and osmotic fragility of human erythrocytes exposed in vitro to 10 mM H2O2 for 60 min at 37 oC have been studied. The following flavonoids;quercetin, rutin and morin significantly protected eryt-hrocytes against lipid peroxidation caused by H2O2. This inhibition of lipid peroxidation could be explained by the presence of at least two hydroxyl groups in ring B of the flavonoid structure, regardless of their positions. However, the flavonoids;quercetin, 3,5,7-trihy- droxy-4'-methoxy flavone-7-rutinoside and 3- hydroxy flavone significantly protected eryt-hrocytes against protein degradation. This inhibition could also be explained by the presence of a hydroxyl group at C-3 in ring C of the flavonoid structure. Quercetin and 3,5,7-trihydroxy-4'- methoxy flvone-7-rutinoside significantly protected erythrocytes against loss of deformability and increased osmotic fragility, indicating that the loss of erythrocyte deformability and the increase in osmotic fragility of erythrocytes exposed to H2O2 are related to protein degradation rather than to lipid peroxidation. The other flavonoids (chrysin, 2-carboxy ethyl dihydroxy flavone, apigenin, cirsimaritin, α-naphto flavone and flavanone) failed to protect erythrocytes against the observed oxidative damages. The results demonstrate the importance of the chemical groups substituted on the basic skeleton of the flavonoids in dictating the type of antioxidant activity, and also demonstrate the hemorheological potentials of flavonoids that have particular protein-antioxidant activities. 展开更多
关键词 ERYTHROCYTE DEFORMABILITY LIPID PEROXIDATION Protein Degradation Oxidative Stress H2O2 FLAVONOIDS structure-activity relationships
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Application of PCA and HCA to the Structure-Activity Relationship Study of Fluoroquinolones 被引量:2
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作者 李小红 张现周 +2 位作者 程新路 杨向东 朱遵略 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期143-148,共6页
Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analy... Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce dimensionality and investigate in which variables should be more effective for classifying fluoroquinolones according to their degree of an-S.pneumoniae activity. The PCA results showed that the variables ELUMO, Q3, Q5, QA, logP, MR, VOL and △EHL of these compounds were responsible for the anti-S.pneumoniae activity. The HCA results were similar to those obtained with PCA.The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with antiS.pneumoniae activity. By using the chemometric results, 6 synthetic compounds were analyzed through the PCA and HCA and two of them are proposed as active molecules with anti-S.pneumoniae, which is consistent with the results of clinic experiments. 展开更多
关键词 structure-activity relationship Density functional theory Principal component analysis Hierarchical cluster analysis
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Toxicity of Selected Imidazolium-based Ionic Liquids on Caenorhabditis elegans: a Quantitative Structure-Activity Relationship Study 被引量:1
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作者 卢丽亚 张颖捷 +1 位作者 陈洁洁 童中华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期423-428,I0001,共7页
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... 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. 展开更多
关键词 Imidazolium-based ionic liquids Caenorhabditis elegans TOXICITY Quantitative structure-activity relationship
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Quantitative structure-activity relationship study on the biodegradation of acid dyestuffs 被引量:9
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作者 LI Yin XI Dan-li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第7期800-804,共5页
Quantitative structure-biodegradability relationships (QSBRs) were established to develop predictive models and mechanistic explanations for acid dyestuffs as well as biological activities. With a total of four desc... Quantitative structure-biodegradability relationships (QSBRs) were established to develop predictive models and mechanistic explanations for acid dyestuffs as well as biological activities. With a total of four descriptors, molecular weight (MW), energies of the highest occupied molecular orbital (EHOMO), the lowest unoccupied molecular orbital (ELUMO), and the excited state (EES), calculated using quantum chemical semi-empirical methodology, a series of models were analyzed between the dye biodegradability and each descriptor. Results showed that EHOMO and Mw were the dominant parameters controlling the biodegradability of acid dyes. A statistically robust QSBR model was developed for all studied dyes, with the combined application of EHOMO and Mw. The calculated biodegradations fitted well with the experimental data monitored in a facultative-aerobic process, indicative of the reliable prediction and mechanistic character of the developed model. 展开更多
关键词 quantitative structure-activity relationship (Qsar acid dyestuff BIODEGRADABILITY DECOLORIZATION
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Quantitative Structure-activity Relationship Study on the Antioxidant Activity of Carotenoids 被引量:2
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作者 孙玉敬 庞杰 +2 位作者 叶兴乾 吕元 李俊 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第2期163-170,共8页
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-act... 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). 展开更多
关键词 quantitative structure-activity relationship antioxidant activity carotenoids
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New Descriptors of Amino Acids and Its Applications to Peptide Quantitative Structure-activity Relationship 被引量:2
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作者 舒茂 霍丹群 +3 位作者 梅虎 梁桂兆 张梅 李志良 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第11期1375-1383,共9页
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 physic... 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. 展开更多
关键词 PEPTIDE quantitative structure-activity relationship principal component analysis genetic algorithm partial least square
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Quantitative Structure-activity Relationship Studies on the Antioxidant Activity and Gap Junctional Communication of Carotenoids 被引量:1
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作者 孙玉敬 吴丹 +3 位作者 刘东红 陈健初 沈妍 叶兴乾 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第9期1362-1372,共11页
The antioxidant and gap junctional communication(GJC) activities of carotenoids are known to be the two main anticancer mechanisms.Quantitative structure-activity relationship(QSAR) models of the two activities we... The antioxidant and gap junctional communication(GJC) activities of carotenoids are known to be the two main anticancer mechanisms.Quantitative 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 chemistry.The 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 better.In addition,the two GJC models have similar,moderate predictive power.The possible mechanisms of antioxidant activity and GJC of carotenoids were discussed. 展开更多
关键词 carotenoids antioxidant activity gap junctional communication multilayer perceptron neural network quantitative structure-activity relationship
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