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Exploring Nonlinear Rheological Behaviors in Entangled Semi-flexible Polymer Melts

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Chinese Journal of Polymer Science 2024年第11期 1811-1823页

作者： Li-Cheng Ma Yong-Jin Ruan Zhen-Hua Wang Yu-Yuan Lu Li-Jia An State Key Laboratory of Polymer Physics and chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of applied chemistry and Engineering University of Science and Technology of China

This study utilizes molecular dynamics simulation to investigate the complex dynamics of entangled semi-flexible polymer *** investigation reveals a significant stress overshoot phenomenon in the systems,demonstrating the intricate interplay between shear rates,chain orientation,and chain stretching ***,the identification of metastable states,characterized by a dual-plateau phenomenon in the shear stress-strain curve at specific Rouse-Weissenberg number WiR,showcases the system’s responsiveness to external perturbations and its transition to stable shear banding ***,the analysis of flow field deviations uncovers a progression of shear bands with increasing WiR,displaying distinct behaviors in the system’s dynamics under different shear rates and chain *** findings challenge established theoretical frameworks and advocate for refined modelling approaches in polymer rheology research.

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Chlorajaponins A—Q,Lindenane-Related Sesquiterpenoid Dimers from Chloranthus japonicus and Their Biological Activities

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Chinese Journal of chemistry 2024年第11期42卷 1247-1259页

作者： Wei-Jiao Feng Yue Gu Pei-Zhi Huang Hong-Ying Yang Rui Zhang Yi-Lin He Ting-Hong Lv Ya Li Kun Gao State Key Laboratory of applied Organic chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhouGansu730000 China Research institute Lanzhou Jiaotong UniversityLanzhouGansu730070 China

Seventeen undescribed lindenane-related sesquiterpenoid dimers,chlorajaponins A—Q(1—17),and 13 reported analogs(18—30)were isolated from Chloranthus japonicus *** 1 possesses an unprecedented 3/5/7/5/5/6/5/3 fused octacyclic scaffold,featuring a 6(5→4)-abeo-lindenane monomer,while 2.exhibits a 3/5/6/6/5/6/5/3 fused octacyclic *** structures were determined through a combination of spectroscopic analyses and X-ray *** 1,2.and 18 demonstrated significant inhibitory effects on lipid accumulation and effectively reduced the levels of triglycerides and total cholesterol,as well as the levels of aspartate aminotransferase and alanine aminotransferase in a HepG2.cell *** addition,compounds 1,2.and 18 significantly suppressed the protein expression of the fatty acid synthase(FASN)and the sterol regulatory element-binding protein 1(SREBP1).Moreover,the anti-inflammatory assay showed that compounds 19—2. and 2. inhibited the NO production induced by lipopolysaccharide in RAW 2.4.7 macrophages with IC50 values of 7.89±0.44,6.2.±0.46,2.98±0.2.,10.77±0.60,and 3.60±0.2.μmol/L.

关键词： Chloranthus japonicus Lindenane-type sesquiterpenoid dimers Lipid-lowering activity Anti-inflammatory activity NMR spectroscopy Natural products X-ray diffraction

Application of "Three-in-One" Strategy Based on MOF-199 in Determination of Phenylenediamine Isomers and Cr(Ⅵ)

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Journal of Analysis and Testing 2024年第1期8卷 28-39页

作者： Yueci Xiang Jiantao Wei Huipeng Sun Ruiyi Zhao Zehua Han Shuangtong Wu Xiaoyan Liu Haixia Zhang State Key Laboratory of applied Organic chemistry and College of chemistry and Chemical Engineering Lanzhou UniversityLanzhou 730000China

Industry progressing caused the pollutants into the surface and groundwater,including organic pollutants such as phenylenediamine(PD)and heavy metals such as Cr(Ⅵ).Herein,a simple"three-in-one"strategy based on MOF-199 was *** MOF-199 catalytic system could be used for the rapid detection of Cr(Ⅵ)and o-phenylenediamine(OPD)in linear ranges of 0.5-50.0μmol/L and 7.0-2.0.0μmol/L,with the limits of detection of 0.1 and 0.5μmol/L,*** method can also efficiently discriminate PD isomers in just 15 ***,Cr(Ⅵ)was reduced to Cr(Ⅲ)and the elimination of OPD was carried *** simple synthesis,high sensitivity,easy operation,and low cost,this method presented a potential platform for on-site detection of pollutants in water samples.

关键词： On-site detection “Three-in-one”strategy Phenylenediamine isomers

Genome mining of sulfonated lanthipeptides reveals unique cyclic peptide sulfotransferases

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2773-2785页

作者： Meng Wang Wen-Wei Li Zhe Cao Jianong Sun Jiang Xiong Si-Qin Tao Tinghong Lv Kun Gao Shangwen Luo Shi-Hui Dong State Key Laboratory of applied Organic chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Although sulfonation plays crucial roles in various biological processes and is frequently utilized in medicinal chemistry to improve water solubility and chemical diversity of drug leads,it is rare and underexplored in ribosomally synthesized and post-translationally modified peptides(RiPPs).Biosynthesis of RiPPs typically entails modification of hydrophilic residues,which substantially increases their chemical stability and bioactivity,albeit at the expense of reducing water *** explore sulfonated RiPPs that may have improved solubility,we conducted co-occurrence analysis of RiPP class-defining enzymes and sulfotransferase(ST),and discovered two distinctive biosynthetic gene clusters(BGCs)encoding both lanthipeptide synthetase(LanM)and *** expressing these BGCs,we characterized the structures of novel sulfonated lanthipeptides and determined the catalytic details of LanM and *** demonstrate that SslST-catalyzed sulfonation is leader-independent but relies on the presence of A ring formed by *** LanM and ST are promiscuous towards residues in the A ring,but ST displays strict regioselectivity toward *** recognition of cyclic peptide by ST was further *** evaluation underscores the significance of the ST-catalyzed *** study sets up the starting point to engineering the novel lanthipeptide STs as biocatalysts for hydrophobic lanthipeptides improvement.

关键词： Lanthipeptides Sulfotransferases Sulfonation Biosynthesis Genome mining

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

Heterocyclic Molecules Tethered Branched Polymers with Innate Immune Stimulating Activity

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CCS chemistry 2024年第5期6卷 1278-1288页

作者： Jiayu Zhao Liping Liu Yibo Wang Zichao Huang Yu Zhang Ruirui Qiao Thomas P.Davis Zhaohui Tang Wantong Song Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 School of applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026 Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 Jilin Biomedical Polymers Engineering Laboratory Changchun 130022 Australian institute of Bioengineering and Nanotechnology The University of QueenslandBrisbaneQueensland 4072

We report herein an interesting finding that heterocyclic molecules tethered branched polymers exhibit innate immune stimulating *** we conjugated a series of five-,six-,or seven-membered heterocyclic molecules to branched polyethylenimine(bPEI),over 70%of them could induce the secretion of interferon-β(IFN-β)from murine dendritic and human leukemia monocytic(DC2.4 and THP-1)cells through activating the stimulator of interferon genes(STING)*** further proved that this kind of innate stimulating activity was dependent on the macromolecular architecture as heterocyclic molecules tethered linear PEI(lPEI)or dendritic polyamidoamine(PAMAM)induced no or much less IFN-β***,we prepared a series of poly-L-lysine(PLL)-derivatives with different branches to tether with heterocyclic molecules and proved that this kind of bPEI-like structure was important in en hancing the binding affinity with STING proteins and for exhibiting innate stimulating activity.

关键词： bioactive materials polymers heterocycles branched structure immunity

Utilizing dual-pathway energy transfer in upconversion nanoconjugates for reinforced photodynamic therapy

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Nano Research 2024年第4期17卷 2941-2948页

作者： Ruohao Zhang Yu Lu Yifei Zhou Kehong Lv Xinyu Fu Jitong Gong Shuang Yao Xiaozhen Wang Jing Feng Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China College of chemistry Jilin UniversityChangchun 130012China Department of Breast Surgery General Surgery Centerthe First Hospital of Jilin UniversityChangchun 130021China Department of chemistry Tsinghua UniversityBeijing 100084China

Enhancing the therapeutic effect of existing treatments or developing new non-invasive treatments are important measures to achieve high-efficiency treatment of malignant *** therapy(PDT)is an emerging treatment modality,and the key for achieving high-efficiency PDT is to select light with strong tissue penetration depth and enhance the generation of reactive oxygen species(ROS).Although the upconversion nanoparticles(UCNPs)modified with the photosensitizers could achieve PDT with strong penetration depth under near-infrared light irradiation,the ROS generated by traditional single-pathway PDT is still ***,we developed a novel nanoconjugate(UCNP-Ce6/AIEgen)for dual-pathway reinforced PDT,in which the UCNPs were co-modified with chlorin e6(Ce6)and luminogen with aggregation-induced emission(AIEgen).Due to the presence of AIEgen,UCNP-Ce6/AIEgen could avoid aggregation-caused luminescence quenching in biological water environments and convert upconversion luminescence(UCL)of UCNPs to Ce6-activatable ***,under the irradiation of 808 nm laser,UCNP-Ce6/AIEgen can not only undergo direct lanthanide-triplet energy transfer to activate Ce6,but also convert the UCL of UCNPs to the light that can activate Ce6 through Fӧrster resonance energy transfer to generate more ROS,thus promoting tumor cell *** work broadens the applications of nanoconjugates of lanthanide-based inorganic materials and organic dyes,and provides a conception for reinforced PDT of tumors.

关键词： upconversion nanoparticle aggregation-induced emission direct lanthanide-triplet energy transfer Förster resonance energy transfer photodynamic therapy

Photoinduced generation of alkyl and phthalimide nitrogen radicals from N-hydroxyphthalimide esters for the synthesis of benzophenone-type bioisosteres

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Science China chemistry 2024年第10期67卷 3389-3396页

作者： Fei Li Jianyang Dong Huijuan Liao Jiayi Dang Xuechen Zhou Yuying Wang Chenya Wang Qin Jiang Gang Li Dong Xue Key Laboratory of applied Surface and Colloid chemistry Ministry of Education and School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an 710119China

N-Hydroxyphthalimide(NHPI)esters have emerged as powerful sources of alkyl radicals generated by single-electron transfer,but homolysis of NHPI ester to produce an alkyl radical and a phthalimide nitrogen radical is still in its *** this study,we developed a light-induced method for generation of alkyl and phthalimide nitrogen radicals from NHPI esters and subsequent reactions of the radicals with[1.1.1]propellane and aryl aldehydes for rapid generation of bicycle[1.1.1]pentane *** method does not require metals or photosensitizers,features a broad substrate scope(90 examples)and excellent functional group tolerance,and can be used for the functionalization of structurally complex natural products and *** investigations indicate that the reaction involves photoinduced homolytic cleavage of the Cs_(2.CO_(3)-NHPI ester complex to produce alkyl and phthalimide nitrogen radicals and subsequent hydrogen atom transfer between the phthalimide nitrogen radical and the aldehyde to generate an acyl radical.

关键词： phthalimide nitrogen radicals aryl aldehydes hydrogen atom transfer bicycle[1.1.1]pentane ketones bioisosteres

Surfactant-metal-organic framework complexes and their derivatives:advances in electrocatalysis

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Science China chemistry 2024年第10期67卷 3209-3222页

作者： Yining Liu Mengying Wang Zuozhong Liang Haoquan Zheng Key Laboratory of applied Surface and Colloid chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an 710119China

Metal-organic frameworks(MOFs)and their derivatives received more and more attention due to the diverse morphologies,rich porous structures,and tunable metal active sites,which have been widely used in energy-related electrocatalytic ***,a class of compounds with hydrophilic and hydrophobic portions in the molecular structure,are able to modulate the properties of liquid and solid *** play a crucial role in controlling the shape and size of MOFs,which helps optimize electrocatalytic performance,especially in improving the exposure and accessibility of catalytic active *** this review,we first outline the types and applications of ***,we describe the interface modulation and reaction mechanism of different surfactants during the forming of MOFs and their ***,we discuss the current applications of surfactant-modified MOFs and their derivatives in *** review provides a better understanding of surfactantassistant structure regulation and electrocatalytic activity study of MOFs and their derivatives.

关键词： metal-organic frameworks surfactants interface modulation electrocatalysis