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Electric-field-controlled highly regioselective thiocyanation of N-containing heterocycles

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Science China Chemistry 2024年第4期67卷 1263-1269页

作者： Ming Gong Qian Wu Jung Keun Kim Mengmeng Huang Yabo Li Yangjie Wu Jong Seung Kim Henan Key Laboratory of chemical biology and Organic Chemistry Key Laboratory of Applied Chemistry of Henan UniversitiesCollege of ChemistryZhengzhou UniversityZhengzhou 450052China department of Chemistry Korea UniversitySeoul 02841Korea

Achieving highly regioselective synthesis in organic chemistry is challenging due to the uncontrollable orientation between reacting *** electric fields(EEFs)can influence the reactivity and selectivity of the substrate by causing directional ***,scalable and efficient techniques for using EEFs as“smart catalysts”have been lacking,hindering their *** this study,we present a novel method for modifying the regioselectivity of quinoxaline-2(1H)-ones by functionalizing their C7-position using the electric double layer(EDL)*** approach led to moderate to good yields of the corresponding C7-thiocyanation *** calculations and control experiments demonstrated that EEFs could reverse the regioselectivity of quinoxaline-2(1H)-ones,allowing the C7-thiocyanation to proceed via a radical reaction ***,the resulting 7-thiocyano-1-methylquinoxaline-2(1H)-ones exhibited promising AIE *** work showcases a promising strategy for achieving highly regioselective functionalization by aligning the electric field with the desired reaction/bond axis.

关键词： electric fields reaction-axis rule electric double layer C7-thiocyanation C-S bond formation

chemical biology investigation of a triple-action,smart-decomposition antimicrobial booster based-combination therapy against“ESKAPE”pathogens

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Science China Chemistry 2024年第9期67卷 3071-3082页

作者： Min Wang Huangsheng Pu Yangfan Xu Chenxuan Wu Yuanxin Gu Qingyun Cai Guoxing Yin Peng Yin Chunhui Zhang Wing-Leung Wong Muyang Wan Yugang Bai Xinxin Feng State Key Laboratory of Chem-/Bio-Sensing and Chemometrics Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biologyand School of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China College of biology Hunan UniversityChangsha 410082China College of Advanced Interdisciplinary Studies&Hunan Provincial Key Laboratory of Novel Nano Optoelectronic Information Materials and Devices National University of Defense TechnologyChangsha 410073China Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China Key Laboratory of chemical biology and Traditional Chinese Medicine Research(Ministry of Education) College of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China State Key Laboratory of chemical biology and Drug Discovery Department of Applied Biology and Chemical TechnologyThe Hong Kong Polytechnic UniversityHong Kong SAR 999077China Hunan Provincial Key Laboratory of Anti-Resistance Microbial Drugs The Third Hospital of Changsha(The Affiliated Changsha Hospital of Hunan University)Changsha 410015China

The global antibiotic resistance crisis necessitates urgent *** innovative approach involves potentiating antibiotics and non-antibiotic drugs with adjuvants or boosters.A major drawback of these membrane-active boosters is their limited biocompatibility,as they struggle to differentiate between prokaryotic and eukaryotic *** study reports the chemical biology investigation of a dual-action oligoamidine(OA1)booster with a glutathione-triggered decomposition ***1,when combined with other antimicrobial molecules,exhibits a triple-targeting mechanism including cell membrane disruption,DNA targeting,and intracellular enzyme *** multi-targeting mechanism not only enhances the in vitro and in vivo eradication of antibiotic-resistant“ESKAPE”pathogens,but also suppresses the development of bacterial ***,OA1 maintains its activity in bacterial cells by creating an oxidative environment,while it quickly decomposes in mammalian cells due to high glutathione *** mechanistic insights and design principles may provide a feasible approach to develop novel antimicrobial agents and effective anti-resistance combination therapies.

关键词： antimicrobial booster oligoamidine membrane disruption DNA targeting triggered degradation anti-resistance

Nonlinear interaction of head-on solitary waves in integrable and nonintegrable systems

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Chinese Physics B 2024年第5期33卷 480-487页

作者：张树甜刘世鲲矫滕菲孙敏胡凤兰黄德财 department of applied Physics Nanjing University of Science and TechnologyNanjing 210094China

This study numerically investigates the nonlinear interaction of head-on solitary waves in a granular chain(a nonintegrable system)and compares the simulation results with the theoretical results in fluid(an integrable system).Three stages(the pre-in-phase traveling stage,the central-collision stage,and the post-in-phase traveling stage)are identified to describe the nonlinear interaction processes in the granular *** nonlinear scattering effect occurs in the central-collision stage,which decreases the amplitude of the incident solitary *** with the leading-time phase in the incident and separation collision processes,the lagging-time phase in the separation collision process is *** asymmetrical nonlinear collision results in an occurrence of leading phase shifts of time and space in the post-in-phase traveling *** next find that the solitary wave amplitude does not influence the immediate space-phase shift in the granular *** space-phase shift of the post-in-phase traveling stage is only determined by the measurement position rather than the wave *** results are reversed in the *** increase in solitary wave amplitude leads to decreased attachment,detachment,and residence times for granular chains and *** the immediate time-phase shift,leading and lagging phenomena appear in the granular chain and the fluid,*** results offer new knowledge for designing mechanical metamaterials and energy-mitigating systems.

关键词： integrable system nonintegrable system granular chain solitary wave

Study of damage behavior and repair effectiveness of patch repaired carbon fiber laminate under quasi-static indentation loading

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Defence technology（防务技术） 2024年第4期34卷 29-41页

作者： Alok Kumar Chinmaya Kumar Sahoo A.Arockiarajan department of applied Mechanics Indian Institute of Technology MadrasChennai 600036India

Damage caused due to low-velocity impacts in composites leads to substantial deterioration in their residual strength and eventually provokes structural *** work presents an experimental investigation on the effects of different patch and parent laminate stacking sequences on the enhancement of impact strength of Carbon Fiber Reinforced Polymers(CFRP)composites by utilising the adhesively bonded external patch repair *** evolution study is also performed with the aid of Acoustic Emission(AE).Two different quasi-isotropic configurations were selected for the parent laminate,viz.,[45°/45°/0°/0°]s and[45°/0°/45°/0°]*** Static Indentation(QSI)test was performed on both the pristine laminates,and damage areas were detected by using the C-scan inspection *** laminates were repaired by using a single-sided patch of two different configurations,viz.,[45°/45°/45°/45°]and[45°/0°/0°/45°],and employing a circular plug to fill the damaged *** different combinations of repaired laminates with two configurations of each parent and patch laminate were produced,which were further subjected to the QSI *** results reveal the effectiveness of the repair method,as all the repaired laminates show higher impact resistance compared to the respective pristine *** of[45°/0°/0°/45°]configuration when repaired by taking[45°/45°/0°/0°]s and[45°/0°/45°/0°]s as parents exhibited 68%and 73%higher peak loads,respectively,than the respective pristine ***,parent and patch of configuration[45°/0°/45°/0°]s and[45°/0°/0°/45°],respectively,attain the highest peak load,whereas[45°/45°/0°/0°]s and[45°/45°/45°/45°]combinations possess the most gradual decrease in the load.

关键词： Carbon fiber reinforced polymers(CFRP) Quasi-isotropic laminate Quasi static indentation(QSI) Acoustic emission(AE) Composite repair

Transition-Metal-Free Allylic Defluorination Cross-Electrophile Coupling Employing Rongalite

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Chinese Journal of Chemistry 2024年第12期42卷 1360-1366页

作者： Xiang-Long Chen Chun-Yan Wu Dong-Sheng Yang Bo-Cheng Tang Huai-Yu Wang Zhi-Cheng Yu Anling Li Yan-Dong Wu An-Xin Wu National Key Laboratory of Green Pesticide International Joint Research Center for Intelligent Biosensor Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhanHubei 430079China state Key Laboratory of chemical biology and Drug Discovery Department of Applied Biology and Chemical Technology The HongKong Polytechnic UniversityKowloonHong Kong SARChina department of Clinical Laboratory Center for Gene Diagnosisand Program of Clinical Laboratory MedicineZhongnan Hospital of Wuhan UniversityWuhanHubei 430062China

Comprehensive Summary The conversion of CF3-alkenes to gem-difluoroalkenes using reductive cross-coupling strategy has received much attention in recent years,however,the use of green and readily available reducing salt to mediate these reactions remains to be *** this work,a concise construction of gem-difluoroalkenes,which requires neither a catalyst nor a metal reducing agent,was ***,a safe and inexpensive industrial product,was employed as both a radical initiator and *** procedure was compatible with both linear and cyclic diaryliodonium salts,enabling a wide variety of substrates(>70 examples).The utility of this approach was demonstrated through gram-scale synthesis and efficient late-stage functionalizations of anti-inflammatory drugs.

关键词： Defluoroarylation Transition metal free gem-Difluoroalkenes Rongalite Single electron transfer C-C coupling Redox reactions Cross-coupling

Volumetric and viscometric properties of aqueous 1,2-dimethylethylenediamine solution for carbon capture application

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Petroleum 2024年第2期10卷 326-337页

作者： Hossein Haghani Teerawat Sema Pipat Na Ranong Thanthip Kiattinirachara Benjapon Chalermsinsuwan Hongxia Gao Zhiwu Liang Paitoon Tontiwachwuthikul department of chemical technology Faculty of Science Chulalongkorn University Center of Excellence on Petrochemical and Materials technology Chulalongkorn University department of chemical Engineering Faculty of Engineering Mahidol University Joint International Center for CO Clean Energy Technologies Research Institute (CETRi) Faculty of Engineering and Applied Science University of Regina

The present work investigates the volumetric and viscometric properties of an aqueous solution of 1,2-dimethylethylenediamine(DEEDA) over an entire concentration range and an absorber operating temperature range of 313.15K-333.15K at atmospheric pressure. The investigated volumetric properties included the density, excess molar volume, partial molar volume, and the investigated viscometric properties included the viscosity, viscosity deviation, free energy for activation of viscous flow, excess free energy for activation of viscous flow, and excess entropy for activation of viscous flow. The results indicated that there are strong intermolecular interactions and suitable molecular packing in the binary DEEDA-water mixture. Hence, the mixture was found to deviate from a real mixture according to the calculated excess properties. The DEEDA solvent's preliminary volumetric and viscometric properties revealed convincing potential as a novel amine for carbon capture. Additionally, the Redlich-Kister-based correlations showed favorable correlative performance for excess molar volume, viscosity deviation, and excess entropy for activation of viscous flow.

关键词： Density Viscosity Excess property Amine Carbon capture

Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of chemical Engineering 2024年第1期65卷 276-285页

作者： Yin Wu Yan Sun department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

Stereoselective recognition of morphine enantiomers by μ-opioid receptor

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National Science Review 2024年第3期11卷 183-191页

作者： Yibo Wang Van A.Ngo Xiaohui Wang Laboratory of chemical biology Changchun Institute of Applied ChemistryChinese Academy of Sciences Advanced Computing for Life Sciences and Engineering Group Science Engagement Section National Center for Computational Sciences Oak Ridge National Lab School of applied Chemistry and Engineering University of Science and Technology of China Beijing National Laboratory for Molecular Sciences

Stereospecific recognition of chiral molecules plays a crucial role in biological systems. The μ-opioid receptor（MOR） exhibits binding affinity towards（-）-morphine, a well-established gold standard in pain management, while it shows minimal binding affinity for the（+）-morphine enantiomer, resulting in a lack of analgesic activity. Understanding how MOR stereoselectively recognizes morphine enantiomers has remained a puzzle in neuroscience and pharmacology for over half-a-century due to the lack of direct observation techniques. To unravel this mystery, we constructed the binding and unbinding processes of morphine enantiomers with MOR via molecular dynamics simulations to investigate the thermodynamics and kinetics governing MOR's stereoselective recognition of morphine enantiomers. Our findings reveal that the binding of（-）-morphine stabilizes MOR in its activated state, exhibiting a deep energy well and a prolonged residence time. In contrast,（+）-morphine fails to sustain the activation state of ***, the results suggest that specific residues, namely D1142.50and D1473.32, are deprotonated in the active state of MOR bound to（-）-morphine. This work highlights that the selectivity in molecular recognition goes beyond binding affinities, extending into the realm of residence time.

关键词： stereoselective recognition thermodynamics and kinetics residence time morphine enantiomers μ-opioid receptor

Heterogeneous crystallization of Chlorzoxazone for modulating the physicochemical properties of crystals Author links open overlay panel

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Particuology 2024年第8期91卷 249-259页

作者： Dhayananth Natarajan Kalaichelvi Ponnusamy Radhakrishnan Thota Karunakaran department of chemical Engineering National Institute of TechnologyTiruchirappalli620015TamilnaduIndia

The polymer on modulating the crystal's habit is an evolving research in pharmaceutical *** study demonstrates the crystal habit modification of chlorzoxazone(CHZ)by heterogeneous crystallization(HC)in the binary solvent acetonitrile-ethanol(A-E(1:1))in the presence of polyvinylpyrrolidine(PVP)at concentrations of 0.50,0.75,and 1.00 wt%.The A-E(1:1)and PVP in HC experiments influenced to change the shape of crystals from needle to plate shape and reduced the crystal size producing a lower aspect ratio(in the range of 1.5-2.3).In the presence of PVP,the CHZ size distribution is 65-78μm which tends to enhance the powder flow-ability of CHZ crystals and as the PVP concentration increases,the nucleation rate *** solubility of size-reduced CHZ crystals at different pH is found to be improved by 1.2-1.4 ***,HC is deemed effective in modifying the physicochemical attributes of CHZ.

关键词： Chlorzoxazone Polyvinylpyrrolidine Heterogeneous crystallization Crystal habit modification Aspect ratio