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Research progress of 3-n-butylphthalide and its derivatives in combating cerebral ischemia
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作者 Hongwei Zheng Yangyang Jiang +7 位作者 Kai Wang Xiao Liu Zihan Jia Xing Su Yanan Zhang Yihua Zhang Zhangjian Huang Yong Ling 《Chinese Journal of Natural Medicines》 2026年第1期13-22,共10页
Ischemic stroke(IS)presents a major threat to human life and health due to its high disability and mortality rates.3-n-Butylphthalide(NBP),derived from celery seeds of the Apiaceae family native to the Mediterranean r... Ischemic stroke(IS)presents a major threat to human life and health due to its high disability and mortality rates.3-n-Butylphthalide(NBP),derived from celery seeds of the Apiaceae family native to the Mediterranean region,was first introduced in China for acute IS treatment in 2004.NBP demonstrates multiple therapeutic actions,including reconstruction of microcirculation in the cerebral ischemia area,inhibition of platelet aggregation,reduction of cerebral infarction volume,maintenance of blood-brain barrier(BBB)integrity,and enhancement of cerebral blood perfusion.However,its overall efficacy remains moderate,limited by poor water solubility and low bioavailability,which constrains its clinical application.To address these limitations,researchers have actively pursued the development of NBP derivatives and analogs,achieving notable progress.These efforts,including substituent introduction,ring opening derivatization,esterification,and atom substitution,have generated diverse NBP derivatives.Several of these derivatives have advanced to clinical studies.Specifically,potassium 2-(1-hydroxypentyl)-benzoate(PHPB),brozopentyl sodium(BZP),and XY-03-EA(ZONK1103)have reached phase II clinical trials,while(S)-2-(1-acetoxypentyl)benzoic acid L-arginine salt(AAPB)has received clinical trial approval for 2024.This review examines the structural modification and optimization of NBP over the past two decades from a medicinal chemistry perspective,aiming to facilitate the development of superior derivatives and advance cerebral ischemia treatment. 展开更多
关键词 Ischemic stroke 3-N-BUTYLPHTHALIDE derivativeS Structural modification Cerebral ischemia
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Prediction of lithium content in typical mountainous clay in Xinjiang,China using fractional derivatives and feature extraction
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作者 JIANG Guo CUI Shichao +6 位作者 CHEN Xi CHEN Xi WANG Jinlin CHEN Tao ZHOU Shuguang ZHANG Zhengfeng XU Xiaozhi 《Journal of Mountain Science》 2026年第2期545-558,共14页
Lithium(Li)is an‘emerging'environmental pollutant,especially in soil,which is a great concern because it can endanger human health through the food chain.Compared with traditional chemical analyses,hyperspectral ... Lithium(Li)is an‘emerging'environmental pollutant,especially in soil,which is a great concern because it can endanger human health through the food chain.Compared with traditional chemical analyses,hyperspectral techniques have achieved many exciting results in soil metal monitoring due to their advantages of being fast and non-destructive.However,insufficient attention has been paid to lithium in soil,and the feasibility of its estimation using hyperspectral techniques needs to be investigated.We studied 97 soil samples from claytype lithium mines in the Ertanggou area of the East Tianshan Mountains of Xinjiang to explore the effects of spectral resolution,fractional order derivatives(FOD),and characteristic band selection on the estimation accuracy of clay Li content,to obtain a fast and effective method for estimating clay Li content.Finally,we developed a new method for rapid and nondestructive estimation of soil lithium content.We have obtained some important results from the study.Spectral resolution exerts a significant impact on model performance,and its reduction usually leads to a decline in model performance.For the full band,the models constructed with low-order derivatives were superior to those with high-order derivatives,and the best model was obtained at the 0.4-order derivative(coefficient of determination(R^(2))and relative predictive deviation(RPD)of 0.777 and 2.118,respectively).In the characteristic bands,the lower order is sensitive to the visible-near-infrared range,and the higher order is sensitive to the short-wave infrared range,and the model constructed with the higher-order derivatives outperforms the lower-order derivatives.In this study,the combination of FOD and Random Forest(RF)can significantly improve the model performance,with R^(2),Relative Root Mean Squared Error(RRMSE),and RPD being 0.849,1.526,and 2.574,respectively.Therefore,this research provides a theoretical basis and technical reference for imaging hyperspectral exploration of anomalous areas of clay-type Li resources. 展开更多
关键词 Hyperspectral remote sensing Fractional order derivatives Random Forest LITHIUM Soil pollutant
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Experimental Validation on a Real-World Truss Structure of a Damage Localization Method Based on Mode Shape Derivatives
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作者 Giada Faraco Andrea Vincenzo De Nunzio +1 位作者 Nicola Ivan Giannoccaro Arcangelo Messina 《Structural Durability & Health Monitoring》 2026年第2期23-38,共16页
Damage detection and localization analysis have gained increasing importance over the years,due to the growing number of catastrophic events and the associated risks that small,undetected cracks in structures may evol... Damage detection and localization analysis have gained increasing importance over the years,due to the growing number of catastrophic events and the associated risks that small,undetected cracks in structures may evolve into severe failures if not identified in time.In this context,vibration-based methods have been extensively investigated for structural damage detection.Among them,one of the most widely used approaches since its introduction is the curvature method.It has been successfully employed in numerous studies,consistently providing reliable results.However,the use of second-order or higher-order derivatives can be challenging when dealing with experimental data,as these are highly sensitive tomeasurement noise.Conversely,using the first derivative may simplify the analysis while maintaining robustness.Therefore,the present work introduces and experimentally demonstrates an extension of the curvature-based approach,focusing on the integration of the first derivative for damage localization.In particular,both methods based on the use of the second and first derivatives were applied to detect their capability in detecting and localizing the damage.This was tested on a slender truss structure,with induced damages at different locations,equal to just 1.069%of the structure volume.The results,obtained from this real-world case study,show that for certain structures,like slender ones,the use of the first derivative can achieve equal or even superior damage detection performance compared to the traditional second derivative method.Specifically,the comparison was evaluated based on the accuracy in localizing the damage with the twomethods,both froma visual and quantitative point of view,since a deviation indexδwas also introduced. 展开更多
关键词 Damage localization mode shapes mode shape derivatives curvature method structural health monitoring
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Electrochromic Devices with High Stability from Colorless to Green Conversion Based on Viologen Derivatives
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作者 PENG Yuyi QIAN Chao +3 位作者 WANG Peng GUO Xu JIANG Chuanyu LIU Ping 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期258-267,共10页
Two viologen derivatives containing fluorine substituent(F)with an asymmetric structures,1,1'-bis(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]dihexafluorophosphate(DFPV)and 1-benzyl-1'-(4-(trifluoromethyl)... Two viologen derivatives containing fluorine substituent(F)with an asymmetric structures,1,1'-bis(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]dihexafluorophosphate(DFPV)and 1-benzyl-1'-(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]di-hexafluorophosphate(Bn-FPV),were synthesized.These viologen derivatives as active materials were used to assemble both flexible and rigid electrochromic devices(ECDs).ECDs based on DFPV exhibited reversible color change from colorless to deep green and ECDs based on Bn-FPV exhibited reversible color change from colorless to blue-green within applied voltage.It was found that the devices based on DFPV showed cycle stability,which could still maintain more than 90% after 1000 cycles.In addition,the modulation rate of the device to the solar irradiance is also calculated to characterize its application potential in smart windows.Among them,the rigid device(R-DFPV)based on the DFPV has a large solar irradiance modulation rate of 54.66%,which has the potential to be used as smart windows. 展开更多
关键词 viologen derivatives electrochromic material flexible electrochromic devices rigid electrochromic device smart windows
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A NIR and ratiometric fluorescent probe for quantitative detection of SO_(2) derivatives in Chinese medicinal materials and bioimaging in vivo
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作者 Meitong Wu Ke Wu +7 位作者 Shumin Feng Li Xu Mi Lei Jianmei Chen Shuang Li Mian Qin Dahui Liu Guoqiang Feng 《Chinese Chemical Letters》 2026年第1期434-439,共6页
Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the q... Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the quality of these medicinal materials and contributing to various health issues.Due to a lack of effective monitoring and imaging tools,the physiological effects of excessive SO_(2) residues in traditional Chinese medicine remain unclear.Therefore,developing a rapid and effective tool for detecting SO_(2) is crucial for understanding its metabolic pathways and effects in vivo.In this study,we developed a near infrared(NIR) and ratiometric fluorescent probe,NIR-RS,which exhibits high sensitivity,selectivity,and rapid response for SO_(2) detection.Notably,NIR-RS accurately quantifies SO_(2) contents in Pinelliae rhizoma(P.rhizoma) samples,with recovery rates from 98.46 % to 102.40 %,and relative standard deviations(RSDs)< 5.0 %.For bioimaging applications,NIR-RS has low cytotoxicity and good mitochondrial-targeting ability,making it suitable for imaging exogenous and endogenous SO_(2) in mitochondria.Additionally,NIR-RS was successfully applied to image SO_(2) content of P.rhizoma samples within cells,revealing that high SO_(2) residue elevated mitochondria adenosine triphosphate(ATP) content,these findings reveal that P.rhizoma with excessive SO_(2) can affect the organism's growth mechanisms through alterations in ATP pathways.In vivo,SO_(2) was found to predominantly accumulate in the liver following gavage with P.rhizoma solution,with accumulation levels increasing in proportion to SO_(2) residue concentration.High SO_(2) concentrations in P.rhizoma can cause pulmonary fibrosis and gastric mucosal damage.This work provides a valuable tool for regulating SO_(2) content in P.rhizoma and may help researcher better understand the metabolism of SO_(2) derivatives and explore their physiological roles in biological systems. 展开更多
关键词 Fluorescent probe SO_(2)derivatives metabolism Quantitative analysis Pinelliae rhizoma Fluorescent imaging
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A Deterministic and Stochastic Fractional-Order Model for Computer Virus Propagation with Caputo-Fabrizio Derivative:Analysis,Numerics,and Dynamics
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作者 Najat Almutairi Mohammed Messaoudi +1 位作者 Faisal Muteb K.Almalki Sayed Saber 《Computer Modeling in Engineering & Sciences》 2026年第3期806-843,共38页
This paper introduces a novel fractional-order model based on the Caputo-Fabrizio(CF)derivative for analyzing computer virus propagation in networked environments.The model partitions the computer population into four... This paper introduces a novel fractional-order model based on the Caputo-Fabrizio(CF)derivative for analyzing computer virus propagation in networked environments.The model partitions the computer population into four compartments:susceptible,latently infected,breaking-out,and antivirus-capable systems.By employing the CF derivative—which uses a nonsingular exponential kernel—the framework effectively captures memory-dependent and nonlocal characteristics intrinsic to cyber systems,aspects inadequately represented by traditional integer-order models.Under Lipschitz continuity and boundedness assumptions,the existence and uniqueness of solutions are rigorously established via fixed-point theory.We develop a tailored two-step Adams-Bashforth numerical scheme for the CF framework and prove its second-order accuracy.Extensive numerical simulations across various fractional orders reveal that memory effects significantly influence virus transmission and control dynamics;smaller fractional orders produce more pronounced memory effects,delaying both infection spread and antivirus activation.Further theoretical analysis,including Hyers-Ulam stability and sensitivity assessments,reinforces the model’s robustness and identifies key parameters governing virus dynamics.The study also extends the framework to incorporate stochastic effects through a stochastic CF formulation.These results underscore fractional-order modeling as a powerful analytical tool for developing robust and effective cybersecurity strategies. 展开更多
关键词 Caputo-Fabrizio derivative fractional-order computer virus model stochastic fractional dynamics Adams-Bashforth scheme Hyers-Ulam stability sensitivity analysis cyber-epidemiology memory effects nonsingular kernel
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Pyrazino[2,3-f][1,10]phenanthroline Derivatives as Photoredox Catalysts for Photoinduced Organocatalyzed Atom Transfer Radical Polymerization(O-ATRP)at ppm-Level Loading
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作者 Wen-Zhe Xu Wan-Chao Hu +1 位作者 Bei Liu Chang-Li Lü 《Chinese Journal of Polymer Science》 2026年第3期664-674,I0009,共12页
Organocatalyzed atom transfer radical polymerization(O-ATRP)is a pivotal technique for the synthesis of polymers with well-defined structures that are devoid of metallic residues.A major challenge in this area is the ... Organocatalyzed atom transfer radical polymerization(O-ATRP)is a pivotal technique for the synthesis of polymers with well-defined structures that are devoid of metallic residues.A major challenge in this area is the reduction of catalyst loading while maintaining precise control over polymer architecture and properties.Herein,we systematically evaluate the efficacy of six pyrazino[2,3-f][1,10]phenanthroline(pyzPhen)-based photoredox catalysts in photoinduced O-ATRP.Experimental results indicate that the introduction of various substituents markedly influences the photophysical properties and redox behavior of the catalysts,thereby resulting in differing catalytic efficiencies in the O-ATRP of methyl methacrylate(MMA).Following additional optimization,two highly efficient O-ATRP photocatalysts capable of exhibiting thermally activated delayed fluorescence(TADF)were successfully identified.Under visible light irradiation,TADF catalysts effectively mediated the controlled polymerization of MMA at a low loading level of 50 ppm,particularly when used in conjunction with the initiator DBMM.The catalytic systems demonstrate excellent temporal control,broad monomer applicability,and favorable compatibility with various initiators and solvent systems.This work offers new insights into the development of efficient,low-catalyst-loading,metal-free ATRP systems. 展开更多
关键词 Organocatalyzedatom transfer radical polymerization(O-ATRP) Photoredox catalysts Pyrazino[2 3-f][1 10]phenanthroline derivatives Thermally activated delayed fluorescence(TADF) Low catalyst loading
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Separation Properties of a New Polysiloxane-Anchored β-Cyclodextrin Derivative as Gas Chromatography Stationary Phase 被引量:1
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作者 史雪岩 傅若农 顾峻岭 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期285-289,共5页
A new capillary gas chromatography stationary phase, monokis (2,6 di O benzyl 3 O propyl (3’)) hexakis(2,6 di O benzyl 3 O methyl) β CD bonded polysiloxane, was synthesized. It ex... A new capillary gas chromatography stationary phase, monokis (2,6 di O benzyl 3 O propyl (3’)) hexakis(2,6 di O benzyl 3 O methyl) β CD bonded polysiloxane, was synthesized. It exhibited separation abilities to disubstituted benzene isomers and some chiral solutes. It was also found that the polarity of CD derivatives can be lowered both by chemically bonding it to polysiloxane and by diluting it in polysiloxane. The separation abilities of the polysiloxane anchored CDs (SP CD) are higher than that of the unbonded CDs (S CD) and the diluted S CD at lower column temperature. Hydrosilylation reaction is one of the best methods to lower the operating temperature of CDs. 展开更多
关键词 capillary gas chromatography stationary phase polysiloxane anchored β cyclodextrin derivative di substituted benzene isomers separation enantiomers separation
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SYNTHESIS AND CHARACTERIZATION OF NOVEL MULTIFUNCTIONAL HOST COMPOUNDS.1.β-CYCLODEXTRIN DERIVATIVE BEARING DIETHANOLAMINE MOIETY 被引量:7
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作者 Bao Jian SHEN Lin Hui TONG Dao Sen JIN Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou,730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第3期205-208,共4页
A novel β-cyclodextrin(β-CD)derivative bearing diethanolamine moiety was synthesized by a convenient method with 63% yield,and the new host compound was characterized by (13)~C-NMR,FT-IR spectra etc,
关键词 ppm SYNTHESIS AND CHARACTERIZATION OF NOVEL MULTIFUNCTIONAL HOST COMPOUNDS.1 cyclodextrin derivative BEARING DIETHANOLAMINE MOIETY
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Novel Bipolar Hosts for Solution-processable Green Phosphorescent OLEDs Based on Tetrasubstituted Carbazole Derivatives 被引量:2
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作者 HUANG Hong ZHANG Youming +2 位作者 HUA Tao LI Nengquan XIE Guohua 《发光学报》 北大核心 2025年第11期1971-1979,共9页
Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compou... Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compounds as host material,high efficiency solution-processed green phosphorescent organic light-emitting diodes(PhOLEDs)have been achieved.The high triplet energies of TBICz and TOXDCz ensure efficient energy transfer from the host to the phosphor and triplet exciton confinement on the phosphor.Solution-processable green phospho⁃rescent devices employing Ir(ppy)3 as vip and the two tetrasubstituted carbazole derivatives as hosts exhibit high ef⁃ficiencies.The best EL performance is achieved for the TBICz-based device,with a maximum current efficiency of 27.3 cd/A,a maximum power efficiency of 15.9 lm/W,and a maximum external quantum efficiency of 7.8%,which provides more host material options for solution-processed OLEDs. 展开更多
关键词 tetrasubstituted carbazole derivatives green phosphorescent organic light-emitting diodes solution-pro⁃cessed bipolar host
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Novel nanoparticles composed of chitosan and β-cyclodextrin derivatives as potential insoluble drug carrier 被引量:5
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作者 Yan-Zuo Chen Yu-Kun Huang +3 位作者 Yuan Chen Ya-Jing Ye Kai-Yan Lou Feng Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第7期909-913,共5页
This research was aim to develop novel cyclodextrin/chitosan (CD/CS) nanocarriers for insoluble drug delivery through the mild ionic gelation method previously developed by our lab. A series of different β- cyclode... This research was aim to develop novel cyclodextrin/chitosan (CD/CS) nanocarriers for insoluble drug delivery through the mild ionic gelation method previously developed by our lab. A series of different β- cyclodextrin (β-CD) derivatives were incorporated into CS nanoparticles including hydroxypropyl-β- cyclodextrin (HP-β-CD), sulphobutylether-β-cyclodextrin (SB-β-CD), and 2,6-di-O-methy-βcyclodex- trin (DM-β-CD). Various process parameters for nanoparticle preparation and their effects on physicochemical properties of CD/CS nanoparticles were investigated, such as the type of CD derivatives, CD and CS concentrations, the mass ratio of CS to TPP (CS/TRP), and pH values. In the optimal condition, CDICS nanoparticles were obtained in the size range of 215-276 nm and with the zeta potential from 30.22 mV to 35.79 mY. Moreover, the stability study showed that the incorporation of CD rendered the CD/CS nanocarriers more stable than CS nanoparticles in PBS buffer at pH 6.8. For their easy preparation and adjustable parameters in nanoparticle formation as well as the diversified hydrophobic core of CD derivatives, the novel CD/CS nanoparticles developed herein might represent an interesting and versatile drug delivery platform for a variety of poorly water-soluble drugs with different physicochemical properties. 展开更多
关键词 Chitosan cyclodextrin derivatives Ionic gelation method Drug delivery system
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Selective binding of bile salts by β-cyclodextrin derivatives with appended quinolyl arms 被引量:4
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作者 Sha-Sha Zhai Yong Chen Yu Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第6期442-446,共5页
Two β-cyclodextrin derivatives bearing appended quinolyl and isoquinolyl arms,i.e.mono-(6-quinolyl- 6-deoxy)-β-cyclodextrin(1) and mono-(6-isoquinolyl-6-deoxy)-β-cyclodextrin(2) were synthesized in satisfac... Two β-cyclodextrin derivatives bearing appended quinolyl and isoquinolyl arms,i.e.mono-(6-quinolyl- 6-deoxy)-β-cyclodextrin(1) and mono-(6-isoquinolyl-6-deoxy)-β-cyclodextrin(2) were synthesized in satisfactory yields and fully characterized.Their original conformations and binding behaviors toward four bile salt vips,that is,sodium cholate(CA),sodium deoxycholate(DCA),sodium glycocholate (GCA),and sodium taurocholate(TCA),were investigated by means of fluorescence,circular dichroism and 2D NMR spectroscopy.The study of solution structures revealed that both quinolyl and isoquinolyl arms were located outside the cyclodextrin cavity.The results obtained from the fluorescence titrations showed that the binding abilities of hosts 1 and 2 with selected bile salts varied in an order of DCA 〉 CA 〉 GCA.The selective binding of hosts toward bile salt vips was discussed from the viewpoints of induced-fit and multiple binding. 展开更多
关键词 cyclodextrin derivatives Bile salts Molecular recognition
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Enhancement of norfloxacin solubility via inclusion complexation with β-cyclodextrin and its derivative hydroxypropyl-β-cyclodextrin 被引量:6
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作者 Gabriel Onn Kit Loh Yvonne Tze Fung Tan Kok-Khiang Peh 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第4期536-546,共11页
The objectives of the study were to investigate the effects of β-cyclodextrin(βCD) and hydroxypropyl-β-cyclodextrin(HPβCD) on the solubility and dissolution rate of norfloxacin prepared using three different metho... The objectives of the study were to investigate the effects of β-cyclodextrin(βCD) and hydroxypropyl-β-cyclodextrin(HPβCD) on the solubility and dissolution rate of norfloxacin prepared using three different methods, at drug to cyclodextrin weight ratios of 1:1, 1:2, 1:4 and 1:8. All the methods increased the solubility and dissolution rate of norfloxacin via inclusion complexation with βCD and HPβCD. Norfloxacin was converted from crystalline to amorphous form through inclusion complexation. Solvent evaporation method was the most effective method in terms of norfloxacin solubilisation, while inclusion complex of HPβCD has higher solubility than βCD complex when prepared using the same procedure. 展开更多
关键词 NORFLOXACIN Inclusion COMPLEXATION cyclodextrins SOLUBILITY DISSOLUTION
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Synthesis of two mono-deoxy β-cyclodextrin derivatives as useful tools for confirming DIBAL-H promoted bis-de-O-methylation mechanism 被引量:1
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作者 Su Long Xiao De Min Zhou +4 位作者 Ming Yang Fei Yu Li He Zhang Pierre Sinay Yong Min Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第12期1315-1318,共4页
Diisobutylaluminium hydride (DIBAL-H) promotes secondary rim regioselective bis-de-O-methylation of permethylated β- cyclodextrin (β-CD) to give diol 2. To gain an insight into the mechanism of this remarkable r... Diisobutylaluminium hydride (DIBAL-H) promotes secondary rim regioselective bis-de-O-methylation of permethylated β- cyclodextrin (β-CD) to give diol 2. To gain an insight into the mechanism of this remarkable regioselective behavior, two corresponding permethylated β-CDs with an alcohol function at either 2- or 3-position were synthesized in our previous study. As a step further to this work, the two compounds were subjected to deoxygenation reaction with tributyltin hydride in the present of 2,2'- azobisisobutyronitrile affording the corresponding 2- and 3-deoxy permethylated β-CD derivatives (19 and 16). The structures of these two compounds were characterized by 1D and 2D NMR and HRMS. Compounds 16 and 19 were unable to react with DIBAL- H which suggests that O-2A and O-3B are necessary for DIBAL-H promoted bis-de-O-methylation reaction of permethylated β-CD. 展开更多
关键词 cyclodextrin (CD) DIBAL-H Deoxy Synthesis MECHANISM
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Direct Enantiomer Separation of 2-PhenylcyclopropanecarboxylateEsters on Cyclodextrin Derivatives Stationary Phases in GC 被引量:1
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作者 Meng Yan NIE Liang Mo ZHOU +2 位作者 Xue Liang LIU Qing Hai WANG Dao Qian ZHU(Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116012) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第11期933-936,共4页
Direct enantiomeric separation of all four optical isomers of 2-phenylcyclopropane carboxylate ester was first achieved on each of the three different beta-cyciodextrin chiral stationary phases (CSPs) in GC. Using the... Direct enantiomeric separation of all four optical isomers of 2-phenylcyclopropane carboxylate ester was first achieved on each of the three different beta-cyciodextrin chiral stationary phases (CSPs) in GC. Using these CSPs, enantiomeric excess of the products of enantioselective cyclopropanation can be determined directly, conveniently and fast. 展开更多
关键词 enantiomer separation 2-phenylcyclopropanecarboxylates cyclodextrin
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Curvularin derivatives from hydrothermal vent sediment fungus Penicillium sp.HL-50 guided by molecular networking and their antiinflammatory activity 被引量:2
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作者 Chunxue Yu Zixuan Xia +6 位作者 Zhipeng Xu Xiyang Tang Wenjuan Ding Jihua Wei Danmei Tian Bin Wu Jinshan Tang 《Chinese Journal of Natural Medicines》 2025年第1期119-128,共10页
Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid ... Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid of curvularin and purine.The structures and absolute configurations of compounds 1-9 were elucidated via nuclear magnetic resonance(NMR)spectroscopy,X-ray diffraction,electronic circular dichroism(ECD)calculations,^(13)C NMR calculation,modified Mosher's method,and chemical derivatization.Investigation of anti-inflammatory activities revealed that compounds 7-9,11,12,14,15,and 18 exhibited significant suppressive effects against lipopolysaccharide(LPS)-induced nitric oxide(NO)production in murine macrophage RAW264.7 cells,with IC_(50)values ranging from 0.44 to 4.40μmol·L^(-1).Furthermore,these bioactive compounds were found to suppress the expression of inflammation-related proteins,including inducible NO synthase(i NOS),cyclooxygenase-2(COX-2),NLR family pyrin domain-containing protein 3(NLRP3),and nuclear factor kappa-B(NF-κB).Additional studies demonstrated that the novel compound 7 possessed potent antiinflammatory activity by inhibiting the transcription of inflammation-related genes,downregulating the expression of inflammation-related proteins,and inhibiting the release of inflammatory cytokines,indicating its potential application in the treatment of inflammatory diseases. 展开更多
关键词 Penicillium sp.HL-50 Curvularin derivatives Molecular networking Anti-inflammatory activity
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Co-regulation effect of solvation and interface of pyridine derivative enabling highly reversible zinc anode 被引量:1
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作者 Binrui Xu Guangbin Wang +3 位作者 Yong Liu Quanan Li Fengzhang Ren Jianmin Ma 《Journal of Materials Science & Technology》 2025年第1期1-9,共9页
The poor reversibility and stability of Zn anodes greatly restrict the practical application of aqueous Zn-ion batteries(AZIBs),resulting from the uncontrollable dendrite growth and H_(2)O-induced side reactions durin... The poor reversibility and stability of Zn anodes greatly restrict the practical application of aqueous Zn-ion batteries(AZIBs),resulting from the uncontrollable dendrite growth and H_(2)O-induced side reactions during cycling.Electrolyte additive modification is considered one of the most effective and simplest methods for solving the aforementioned problems.Herein,the pyridine derivatives(PD)including 2,4-dihydroxypyridine(2,4-DHP),2,3-dihydroxypyridine(2,3-DHP),and 2-hydroxypyrdine(2-DHP),were em-ployed as novel electrolyte additives in ZnSO_(4)electrolyte.Both density functional theory calculation and experimental findings demonstrated that the incorporation of PD additives into the electrolyte effectively modulates the solvation structure of hydrated Zn ions,thereby suppressing side reactions in AZIBs.Ad-ditionally,the adsorption of PD molecules on the zinc anode surface contributed to uniform Zn deposi-tion and dendrite growth inhibition.Consequently,a 2,4-DHP-modified Zn/Zn symmetrical cell achieved an extremely long cyclic stability up to 5650 h at 1 mA cm^(-2).Furthermore,the Zn/NH_(4)V_(4)O_(10)full cell with 2,4-DHP-containing electrolyte exhibited an outstanding initial capacity of 204 mAh g^(-1),with a no-table capacity retention of 79%after 1000 cycles at 5 A g^(-1).Hence,this study expands the selection of electrolyte additives for AZIBs,and the working mechanism of PD additives provides new insights for electrolyte modification enabling highly reversible zinc anode. 展开更多
关键词 Zn anode Pyridine derivative Electrolyte additive Solvation regulation Interface modification
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Fluorescent coordination polymers based on anthracene-and pyrene-derivative ligands
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作者 XI Jiming TENG Yukang +1 位作者 ZHANG Rui LU Zhenzhong 《无机化学学报》 北大核心 2025年第5期847-854,共8页
We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),campho... We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5. 展开更多
关键词 coordination polymer anthracene derivatives pyrene derivatives FLUORESCENCE
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Preparation of a Cyclomaltoheptaose(β-cyclodextrin) Cross-linked Chitosan Derivative via Glyoxal or Glutaraldehyde 被引量:6
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作者 Wei Liang XU Ji Dong LIU Yan Ping SUN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第7期767-770,共4页
A cyclomaltoheptaose--cyclodextrin (-CD) crosslinked chitosan derivative via glyoxal or glutaraldehyde was prepared. The structures of -CD crosslined chitosan with glyoxal or glutaraldehyde were characterized by IR s... A cyclomaltoheptaose--cyclodextrin (-CD) crosslinked chitosan derivative via glyoxal or glutaraldehyde was prepared. The structures of -CD crosslined chitosan with glyoxal or glutaraldehyde were characterized by IR spectra. The surface morphology of the -CD crosslinked chitosan particles was examined using a scanning electron microscope. The immobilization capacity of ?CD on chitosan was affected on the weight ratio of -CD/chitosan, the utilization amount of crosslinking agent, the acidity of the reaction system and the temperature. The adsorption for nicotine indicated that the chitosan--CD was a good adsorbent. 展开更多
关键词 Chitosan--cyclodextrin adsorbent preparation.
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