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Recent progress in carbene-catalyzed fluoroalkylation

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Science China Chemistry 2024年第8期67卷 2448-2460页

作者： bei Zhang Xuan Zhang jian Wang jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, which has attracted numerous scientists from different fields. This review focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past two decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents with various electronic characteristics, whether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lewis base catalysis, Umploung catalysis, radical catalysis and others. Meanwhile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis

Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery

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Petroleum Science 2024年第2期21卷 974-986页

作者： Xi-Dao Wu Peng Xiao bei Liu Guang-Jin Chen jian-Hua Pang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Ocean Intelligence Technology Center Shenzhen Institute of Guangdong Ocean UniversityShenzhen518120GuangdongChina

CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility ***,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely *** this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil ***,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT ***,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary ***,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were *** results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) *** inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was ***_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water ***,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,*** work may provide guidelines for EOR using CO_(2) emulsions with high water cut.

关键词： CO_(2)/H_(2)O emulsion High water cut CO_(2) mobility control Enhanced oil recovery

One-pot and One-step Cu(0)-mediated Reversible-Deactivation Radical Polymerization of N-Isopropylacrylamide(NIPAM) in Water

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Chinese Journal of Polymer Science 2024年第1期42卷 1-6,I0004页

作者： Zi-Shan Li Jing Lyu bei Qiu Ying-Hao Li Ruth Foley Ri-jian Song Melissa Johnson Qiang Geng Wen-Xin Wang Institute of Precision Medicine(AUST-IPM) Anhui University of Science and TechnologyHuainan 232001China Charles Institute of Dermatology School of MedicineUniversity College DublinDublin D04 V1W8Ireland

Copper(0)-mediated reversible-deactivation radical polymerization(Cu(0)-mediated RDRP) of the water-soluble monomer Nisopropylacrylamide(NIPAM) has been challenging with the problems of high dispersity, poor control over the molecular weights(MWs) or complex or multi reaction steps, etc. In this work, we report the well-controlled polymerization of NIPAM in water via a facile one-pot and one-step Cu(0)-mediated RDRP. The results of this approach show that the key for kicking off the Cu(0)-mediated NIPAM RDRPs is to ensure sufficient Cu~I at the very beginning, and the key to achieve a well-controlled chain growth is to provide adequate deactivation strength during the polymerization process. For NIPAM, which has a high propagation rate constant, the deactivation control can be effectively enhanced by extra adding deactivator(i.e., Cu~II) to the system. Moreover, a low reaction temperature(4 ℃) is necessary in the controlled synthesis of higher MW poly(Nisopropylacrylamide)(PNIPAM) to avoid the compromise in control caused by the phase transition from its lower critical solution temperature(LCST). Through this new kinetically controlled strategy, PNIPAMs with well-defined structure, narrow molecular weight distributions(MWDs) and varied MWs were successfully achieved.

关键词： Cu(0)-mediated RDRP N-isopropylacrylamide Propagation Deactivation Reaction parameters

Unleashing the Power of Bio-based Thermotropic Liquid Crystal Modifiers:Toughening and Reinforcing Petroleum-based Epoxy Resin without Compromising Other Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1093-1102页

作者： Qing-Yun Lu Hong-Wei Gu Jia-Hui Li Qian-Qian Fan bei-Tao Liu Yan Kou Xi-Gao jian Zhi-Huan Weng State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsLiaoning Technology Innovation Center of High Performance Resin MaterialsDepartment of Polymer Science&EngineeringDalian University of TechnologyDalian 116024China Thermochemistry Laboratory Liaoning Province Key Laboratory of Thermochemistry for Energy and MaterialsDalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus,mechanical strength,and other properties is still a big challenge in view of the *** this study,a bio-based liquid crystal epoxy resin(THMT-E P)with an s-triazine ring structure was utilized to modify a petroleum-based bisphenol A epoxy resin(E51)with 4,4'-diaminodiphenylsulfone(DDS)as a curing agent,and the blended systems were evaluated for their thermal stability,mechanical properties,and flame *** results showed that the impact strength of the blended system initially increased and then decreased with the increase in THMT-EP content,and it reached the a maximum value of 26.5 kJ/m^(2)when the THMT-EP content was 5%,which was 31.2%higher than that of E51/***,the flexural strength,modulus,and glass transition tem perature of the blended system were all simultaneously improved with the addition of *** the same time,the addition of THMT-EP enhanced the flame retardancy of the system by increasing the char yield at 700℃and decreasing the peak heat release rate and total heat release *** work paves the way for a more sustainable improvement in the comprehensive performance of epoxy resin.

关键词： Epoxy resin Toughening Bio-based Thermotropic liquid crystal

Serum Iron Overload Activates the SMAD Pathway and Hepcidin Expression of Hepatocytes via SMURF1

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Journal of Clinical and Translational Hepatology 2024年第3期12卷 227-235页

作者： Ning Zhang Pengyao Yang Yanmeng Li Qin Ouyang Fei Hou Guixin Zhu bei Zhang jian Huang Jidong Jia Anjian Xu Experimental and Translational Research Center Beijing Friendship HospitalCapital Medical UniversityBeijingChina Department of Gastroenterology Beijing Shunyi HospitalBeijingChina Department of Critical Liver Diseases Beijing Friendship HospitalCapital Medical UniversityBeijingChina MOE Key Laboratory of Protein Science School of Life SciencesTsinghua UniversityBeijingChina Liver Research Center Beijing Friendship HospitalCapital Medical UniversityBeijingChina

Background and Aims:Liver iron overload can induce hepatic expression of bone morphogenic protein(BMP)6 and activate the BMP/SMAD ***,serum iron overload can also activate SMAD but does not induce BMP6 ***,the mechanisms through which serum iron overload activates the BMP/SMAD pathway remain *** study aimed to clarify the role of SMURF1 in serum iron overload and the BMP/SMAD ***:A cell model of serum iron overload was established by treating hepatocytes with 2 mg/mL of holo-transferrin(Holo-Tf).A serum iron overload mouse model and a liver iron overload mouse model were established by intraperitoneally injecting 10 mg of Holo-Tf into C57BL/6 mice and administering a high-iron diet for 1 week followed by a low-iron diet for 2 *** blotting and real-time PCR were performed to evaluate the activation of the BMP/SMAD pathway and the expression of ***:Holo-Tf augmented the sensitivity and responsiveness of hepatocytes to *** E3 ubiquitin-protein ligase SMURF1 mediated Holo-Tf-induced SMAD1/5 activation and hepcidin expression;specifically,SMURF1 expression dramatically decreased when the serum iron concentration was ***,the expression of SMURF1 substrates,which are important molecules involved in the transduction of BMP/SMAD signaling,was significantly ***,in vivo analyses confirmed that SMURF1 specifically regulated the BMP/SMAD pathway during serum iron ***:SMURF1 can specifically regulate the BMP/SMAD pathway by augmenting the responsiveness of hepatocytes to BMPs during serum iron overload.

关键词： BMP/SMAD pathway Hepcidin Holo-transferrin Ubiquitin-proteasome degradation Hemochromatosis

METTL5 promotes gastric cancer progression via sphingomyelin metabolism

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1925-1946页

作者： Ya-Qiong Zhang jian Li Zhe Qin De-Ming Li Fang-Zhou Ye Song-Hua bei Xiao-Hong Zhang Li Feng Endoscopy Center Minhang Hospital Affiliated to Fudan UniversityShanghai 201100China

BACKGROUND The treatment of gastric cancer(GC)has caused an enormous social burden *** studies have reported that N6-methyladenosine(m6A)is closely related to tumor ***5 is a m6A methyltransferase that plays a pivotal role in maintaining the metabolic stability of ***,its aberrant regulation in GC has not been fully *** To excavate the role of METTL5 in the development of *** METTL5 expression and clinicopathological characteristics were analyzed via The Cancer Genome Atlas dataset and further verified via immunohistochemistry,western blotting and real-time quantitative polymerase chain reaction in tissue microarrays and clinical *** tumor-promoting effect of METTL5 on HGC-27 and AGS cells was explored in vitro by Cell Counting Kit-8 assays,colony formation assays,scratch healing assays,transwell assays and flow *** tumor-promoting role of METTL5 in vivo was evaluated in a xenograft tumor *** EpiQuik m6A RNA Methylation Quantification Kit was used for m6A ***,liquid chromatography-mass spectrometry was used to evaluate the association between METTL5 and sphingomyelin metabolism,which was confirmed by Enzyme-linked immunosorbent assay and rescue *** addition,we investigated whether METTL5 affects the sensitivity of GC cells to cisplatin via colony formation and transwell *** Our research revealed substantial upregulation of METTL5,which suggested a poor prognosis of GC *** METTL5 expression indicated distant lymph node metastasis,advanced cancer stage and pathological *** increased level of METTL5 correlated with a high degree of m6A ***5 markedly promotes the proliferation,migration,and invasion of GC cells in ***5 also promotes the growth of GC in animal ***5 knockdown resulted in significant changes in sphingomyelin metabolism,which implies that METTL5 may impact the development of GC via sphin

关键词： Gastric cancer METTL5 Sphingomyelin metabolism Cisplatin

Emergent Geometry of KP Hierarchy

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Acta Mathematica Sinica,English Series 2024年第1期40卷 3-25页

作者： jian ZHOU Department of Mathematical Sciences Tsinghua UniversityBeijng 100084P.R.China

We explain how to construct a quantum deformation of a spectral curve associated to a tau-function of the KP *** construction is applied to Witten-Kontsevich tau-function to give a natural explanation of some earlier ... 详细信息

关键词： KP hierarchy tau-functions spectral curves

Chalcone derivatives as novel,potent and selective inhibitors against human Notum:Structure–activity relationships and biological evaluations

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Chinese Chemical Letters 2024年第3期35卷 321-325页

作者： Jin-Hui Shi bei Zhao Li-Lin Song Yu-Qing Song Meng-Ru Sun Tian Tian Hong-Yu Chen Yun-Qing Song jian-Ming Sun Guang-Bo Ge Shanghai Frontiers Science Center of TCM Chemical Biology Institute of Interdisciplinary Integrative Medicine Research Shanghai University of Traditional Chinese MedicineShanghai 201203China Dalian Engineering Research Center for Carbohydrate Agricultural Preparations Liaoning Provincial Key Laboratory of CarbohydratesDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine Shanghai 200137China

Human Notum(hNotum)inhibitors could be used for treating Wnt signalling-associated diseases including colorectal ***,two series of chalcone derivatives were designed and synthesized aiming to find selective and potent hNotum ***–activity relationship(SAR)studies showed that 2-methoxyl and 5-bromine substitutions on A-ring significantly enhanced anti-hNotum effect,while 4’-ethoxyl and 3’-alkyl substitutions on B-ring were beneficial for hNotum *** all tested chalcones,B11 displayed the most potent anti-Notum effect(IC_(50)=3.6 nmol/L),good selectivity,excellent chemical stability and suitable metabolic *** investigations showed that B11 acted as a competitive inhibitor of hNotum,while this agent(5μmol/L)significantly weaken the migration abilities of colorectal cancer ***,this study deciphers the SARs of chalcones as hNotum inhibitors and reports a novel and potent hNotum inhibitor with the anti-migration effect on colorectal cancer cells,which offers a promising lead compound to develop novel anti-cancer agents.

关键词： Human notum(hNotum) Chalcone Computer-assisted drug discovery Structure–activity relationship(SAR) Anti-colorectal cancer agent

Efficacy and safety of targeted therapy plus immunotherapy combined with hepatic artery infusion chemotherapy (FOLFOX) for unresectable hepatocarcinoma

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World Journal of Gastroenterology 2024年第17期30卷 2321-2331页

作者： Zhi-Peng Lin Xiao-Long Hu Du Chen Da-bei Huang Xu-Gong Zou Hai Zhong Sheng-Xiang Xu Yuan Chen Xiao-Qun Li jian Zhang Department of Interventional Medicine Zhongshan People’s HospitalZhongshan 528400Guangdong ProvinceChina

BACKGROUND The advent of cutting-edge systemic therapies has driven advances in the treatment of hepatocellular carcinoma(HCC),and therapeutic strategies with multiple modes of delivery have been shown to be more efficacious than ***,the mechanisms underlying this innovative treatment modality have not been *** To evaluate the clinical efficacy of targeted therapy plus immunotherapy combined with hepatic arterial infusion chemotherapy(HAIC)of FOLFOX in patients with unresectable *** We enrolled 53 patients with unresectable HCC who received a combination of targeted therapy,immunotherapy,and HAIC of FOLFOX between December 2020 and June 2021 and assessed the efficacy and safety of the treatment *** The objective response rate was 60.4%(32/53),complete response was 24.5%(13/53),partial response was 35.9%(19/53),and stable disease was 39.6%(21/53).The median duration of response and median progression-free survival were 9.1 and 13.9 months,*** surgical conversion rate was 34.0%(18/53),and 1-year overall survival was 83.0%without critical complicating diseases or adverse events(AEs).CONCLUSION The regimen of HAIC of FOLFOX,targeted therapy,and immunotherapy was curative for patients with unresectable HCC,with no serious AEs and a high rate of surgical conversion.

关键词： Hepatocellular carcinoma Hepatic arterial infusion chemotherapy Targeted therapy Immunotherapy Adverse events