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Journal of Pharmaceutical Analysis 2018年第2期8卷 124-130页

作者： Satar Tursynbolat Yrysgul Bakytkarim Jianzhi Huang Lishi Wang School of Chemistry and Chemical Engineering South China University of Technology

An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has been developed for highly selective and highly sensitive determination of an antimicrobial drug, metronidazole. The preparation of polydopamine/MWCNTs–COOH nanocomposites/GCE sensor is simple and possesses high reproducible, where polydopamine can be coated on the surface of MWCNTs–COOH via a simple electropolymerization process. Under optimized conditions, the proposed sensor showed ultrasensitive determination for metronidazole with a wide linear detection range from5 to 5000 mmol/dm^3 and a low detection limit of 0.25 mmol/dm^3(S/N=3). Moreover, the proposed sensor has been successfully applied for the quantitative determination of metronidazole in real drug samples. This work may provide a novel and effective analytical platform for determination of metronidazole in application of real pharmaceutical and biological samples analysis.

关键词： Metronidazole Polydopamine carboxylic multi-walled carbon nanotubes Nanocomposites Electrochemical determination Electrochemical sensor

Dichloromethane as a methylene synthon for regioselective linkage of diverse carboxylic acids:Direct access to methylene diesters under metal-free conditions

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Chinese Chemical Letters 2019年第6期30卷 1173-1177页

作者： Shuiliang Wang Zhengjiang Fu Zhicong Huang Yongqing Jiang Shengmei Guo Hu Cai College of Chemistry Nanchang University Nanchang 330031 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter CAS Fuzhou 350002 China

A metal-free cross coupling between common CH2Cl2 and carboxylic acids has been achieved with K2CO3 as the sole additive. This simple protocol is a convenient and cost-effective route to synthesize methylene diesters from a wide scope of carboxylic acids substrates with good functional group tolerance. Several gram-scale reactions have been performed to evaluate the effectiveness and practicality of this protocol.

关键词： carboxylic acids Dichloromethane Methylene synthon Methylene diesters Metal-free conditions

Resolution of racemic R.S-α-arylethylamine by a new resolving agent (R)thiazolidine-2-thione-4-carboxylic acid

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Science China Chemistry 1998年第4期41卷 361-370页

作者：李叶芝郭纯孝卜卫明黄化民 Department of Chemistry Jilin University Changchun China

Racemic R.S α arylethylamine was resolved by R（-）thiazolidine 2 thione 4 carboxylic acid, a new resolving agent abbreviated as , by which R（-）TTCA·S（-） arylethylamine salts 2a - 2e, 20 D= -47.24°\-64.40° and optically active R（+） α arylethylamines 3a - 3e , 74.54%\94.45% e.e., were obtained. Optically active S（-） α arylethylamines 4a - 4e , 72.84%\90.36% e.e., were obtained by the decomposition of 2a - 2e in basic solutions. The influence of substitutive group of the benzene ring on the basicity of the amino group was studied by semiempirical PM3 method. The structures of the R（-）TTCA·S（-） α phenylethylamine salt （2a（R S） configuration） and R（-）TTCA·R（+） α phenylethylamine salt （2a′（R R） configuration） have been established by means of X ray diffraction. They crystallize in a monoclinic system. Space group is P 2 l. The cell constants of 2a（R S） configuration were obtained as follows: a =1.387 8（2）, b =0.664 05（10）, c =1.580 0（2） nm; β =90 844（10）°, Z=4 ; those obtained for 2a′（R R） configuration were a= 1.080 6（2）, b =0.584 80（12）, c = 1.218 8（2） nm, β =110.38（3）°, V =0.722 0 nm 3, Z =2. There are intermolecular hydrogen bonds in the crystals of the two kinds of configurations of the amine salt. The hydrogen bond number in the unit cell of R（-）TTCA·S（-） α phenylethylamine salt is twice as much as that of R（-）TTCA·R（+） α phenylethylamine salt.

关键词： new resolving agent R(-) thiazolidine 2 thione 4 carboxylic acid R(+) α arylethylamine S(-) α arylethylamine resolution electronic structure crystal structure intermolecular hydrogen bond.

Fabrication of carboxylic graphene oxide-composited polypyrrole film for neurite growth under electrical stimulation

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Frontiers of Materials Science 2019年第3期13卷 258-269页

作者： Chaoyuan LIU Zhongbing HUANG Ximing PU Lei SHANG Guangfu YIN Xianchun CHEN Shuang CHENG College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

An aligned composite film was fabricated via the deposition of carboxylic graphe ne oxide(C-GO)and polypyrrole(PPy)nano particles on alig ned poly(L-lactic acid)(PLLA)fiber-films(named as C-GO/PPy/PLLA),which has the core(PLLA)-sheath(C-GO/PPy)structure,and the composition of C-GO(~4.8 wt.%of PPy sheath)significantly enhanced the tensile strength and the conductivity of the PPy/PLLA film?Especially,after 4 weeks of immersion in the PBS solution,the conductivity and the tensile strength of CGO/PPy/PLLA films still remained-6.10 S/cm and 28.9 MPa,respectively,which could meet the need of the sustained electrical stimulation(ES)therapy for nerve repair.Moreover,the neurite length and the neurite alignment were significantly in creased through exerting ES on C-GO/PPy/PLLA films due to their sustained conductivity in the fluid of cell culture.These results indicated that C-GO/PPy/PLLA with sustained conductivity and mechanical property possessed great potential of nerve repair by exerting lasting-ES.

关键词： sustained conductivity electrical stimulation carboxylic graphene oxide polypyrrole

1,2-Dibromoethane and KI mediated α-acyloxylation of ketones with carboxylic acids

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Chinese Chemical Letters 2020年第3期31卷 711-714页

作者： Xujie Wang Gangsheng Li Yanan Yang Jianshuang Jiang Ziming Feng Peicheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

The 1,2-dibromoethane-and Kl-mediatedα-acyloxylation of ketones is reported in moderate to good yield without the use of transition metals and strong oxidants.Various acids are well tolerated with wide functional group compatibility.An 1,2-dibromoethane-and Kl-catalysed reaction mechanism is proposed based on the results of control experiments.

关键词： 1,2-Dibromoethane KI α-Acyloxylation Ketones carboxylic acids

Selective esterification of non-conjugated carboxylic acids in the presence of conjugated or aromatic carboxylic acids over active carbon supported methanesulfonic acid

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Science China Chemistry 2008年第10期51卷 990-992页

作者： FENG ZeWang ZHAO XinQi BI Hua School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Huaxi Technology Co. Ltd.Beijing 102206China

Non-conjugated carboxylic acids are selectively esterified in good yields in the presence of conjugated or aromatic carboxylic acids by stirring over active carbon supported methanesulfonic acid in di-chloromethane at... 详细信息

关键词： esters esterification conjugation catalysis carboxylic acids

Synthesis and structure-insecticidal activity relationship of novel phenylpyrazole carboxylic acid derivatives containing fluorine moiety

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Chinese Chemical Letters 2020年第3期31卷 739-745页

作者： Baolei Wang Hongxue Wang Hang Liu Lixia Xiong Na Yang Yan Zhang Zhengming Li State Key Laboratory of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

A series of novel phenylpyrazole carboxylic acid derivatives containing fluorine moiety,i.e.,diamides 11,simple aryl-bearing amides 12 and acylthioureas 14 were successfully synthesized based on the key fluo ro-containing phe nylpyrazole acid intermediate.The new compounds were identified and confirmed by melting point,1H NMR,13C NMR and elemental analysis or HRMS.The bioassay results indicated that some of the compounds possessed excellent insecticidal activities towards oriental armyworm,diamondback moth and corn borer at low concentrations.For examples,compounds 11a,11e-g and 14b exhibited remarkable larvicidal activities with LC50 values of 0.13-0.39 mg/L and 0.0002-0.0014 mg/L against oriental armyworm and diamondback moth,respectively,were comparable with those of the control chlorantraniliprole.Particularly,lie were found superior to chlorantraniliprole in oriental armyworm tests(LC50:0.23 mg/L vs.0.26 mg/L);11a,lie,11f and 14c in diamondback moth tests with LC50 values of 0.0002 mg/L,0.0002 mg/L,0.0008 mg/L and 0.0005 mg/L,respectively,we re more effective than that of chlorantraniliprole.In addition,12 a also showed a promising insecticidal potential and development/optimization advantage.Compounds 11a,lle-g,12a,14b and 14c could be considered as possible new leading structures for further study.The SAR investigation indicated that the compounds with fluorine motif(e.g.,-F,-CF2H,-CF3)held apparently favorable insecticidal potentials,which provided useful guidance for further design/development of new phenylpyrazole-containing agrochemicals.

关键词： Phenylpyrazole carboxylic acid derivatives Fluorochemicals Synthesis Insecticidal activity Structure-activity relationship

Using benzene carboxylic acids to prepare zirconium-based catalysts for the conversion of biomass-derived furfural

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International Journal of Coal Science & Technology 2018年第4期5卷 464-472页

作者： Huacong Zhou Yufei Sha Zhenhuan Xiao Lu Li Jianmin Hao Keli Yang Na Li Runxia He Quansheng Liu College of Chemical Engineering Inner Mongolia University of Tech no logyInner Mongolia Key Laboratory of High-Value Functional Utilization of Low Rank Carbon ResourcesNo.49 Aimin Road Xincheng DistrictHuhhot 010051Inner MongoliaChina

Benzene carboxylic acid (BCAs) are common and useful chemical blocks, which can be derived from the abundant low rank coals (LRCs) via oxidative degradation. In this work, we proposed a novel strategy to utilize BCAs as raw materials to prepare catalysts with transition metal zirconium, and the prepared catalysts were applied into the conversion of the renewable biomass resources. Typical model BCAs in the oxidative products of LRCs, including pyromellitic acid, trimesic acid (TMSA), trimellitic acid, and benzoic acid, were used as the block to construct the Zr- BCAs catalysts. The chemoselective conversion of furfural into furfuryl alcohol (FAL). an important reaction in the biomass conversion chain, is chosen to evaluate the activity of the catalysts. The preparation conditions of the catalysts and experiment factors during the reaction were systematically investigated. The prepared catalysts were characterized by SEM, TEM, XRD and TG-DTG. The results showed that the prepared catalysts were efficient for the conversion of furfural into FAL, among which Zr-TMSA gave the highest activity. Zr-TMSA could be recycled for ten times without obvious deactivation, indicating an excellent stability. The strategy proposed in this work may be beneficial for the value-added utilization of both LRCs and biomass resources.

关键词： Benzene carboxylic acids Low rank coals Zirconium catalyst Biomass Furfural

Orthosteric ligand selectivity and allosteric probe dependence at Hydroxycarboxylic acid receptor HCAR2

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Signal Transduction and Targeted Therapy 2023年第10期8卷 5059-5068页

作者： Lin Cheng Suyue Sun Heli Wang Chang Zhao Xiaowen Tian Ying Liu Ping Fu Zhenhua Shao Renjie Chai Wei Yan Department of Otolaryngology Head and Neck Surgery Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610000China Division of Nephrology and Kidney Research Institute State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuan 61041China Frontiers Medical Center Tianfu Jincheng LaboratoryChengdu 610212China State Key Laboratory of Digital Medical Engineering Department of Otolaryngology Head and Neck SurgeryZhongda HospitalSchool of Life Sciences and TechnologyAdvanced Institute for Life and HealthJiangsu Province High-Tech Key Laboratory for Bio-Medical Research Southeast UniversityNanjing 210096China Co-Innovation Center of Neuroregeneration Nantong UniversityNantong 226001China

Hydroxycarboxylic acid receptor 2(HCAR2),a member of Class A G-protein-coupled receptor(GPCR)family,plays a pivotal role in anti-lipolytic and anti-inflammatory effects,establishing it as a significant therapeutic tar... 详细信息

关键词： selectivity carboxylic establishing

Determiners of cell fates: the tricarboxylic acid cycle versusthe citrate-malate shuttle

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Protein & Cell 2023年第3期14卷 162-164页

作者： Dong Guo Haiyan He Ying Meng Shudi Luo Zhimin Lu Zhejiang Provincial Key Laboratory of Pancreatic Disease The First Affliated Hospitaland Institute of Translational MedicineZhejiang University School of MedicineZhejiang UniversityHangzhou 310029China Cancer Center Zhejiang UniversityHangzhou 310029China

The tricarboxylic acid(TCA)cycle identified in 1937 by Hans Adolf Krebs and William Arthur Johnson(also known as the Krebs cycle or citric acid cycle)is a central route for oxidative metabolism to generate cellular energy and intermediates for the biosynthesis of amino acids,lipids,and nucleic acids(Krebs and Johnson 1937).The TCA cycle connects carbohydrate,fat,and protein metabolism and converts these nutrient catabolism-derived acetyl-CoA into carbon dioxide and water,with the production of reduced NAD+(NADH),reduced flavin adenine dinucleotide(FADH2),and guanosine triphosphate(GTP).The generated NADH and FADH2 are,in turn,used by the oxidative phosphorylation pathway to generate energy-rich adenosine triphosphate(ATP)(Chakrabarty and Chandel 2021).

关键词： cycle oxidative carboxylic