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Molybdenum-doped carbon nitride as an efficient heterogeneous catalyst for direct amination of nitroarenes with arylboronic acids 被引量:2
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作者 Wen-Jing Li Jun-Bo Wang +2 位作者 Yu-Heng Liu Mo Zhang Zhan-Hui Zhang 《Chinese Chemical Letters》 2025年第3期282-289,共8页
Heterogeneous metal-catalyzed chemical conversions with a recyclable catalyst are very ideal and challenging for sustainable organic synthesis.A new bipyridyl-Mo(IV)-carbon nitride(CN-K/Mo-Bpy)was prepared by supporti... Heterogeneous metal-catalyzed chemical conversions with a recyclable catalyst are very ideal and challenging for sustainable organic synthesis.A new bipyridyl-Mo(IV)-carbon nitride(CN-K/Mo-Bpy)was prepared by supporting molybdenum complex on C_(3)N_(4)-K and characterized by FT-IR,XRD,SEM,XPS and ICP-OES.Heterogeneous CN–Mo-Bpy catalyst can be applied to the direct amination of nitroarenes and arylboronic acid,thus constructing various valuable diarylamines in high to excellent yields with a wide substrate scope and good functional group tolerance.It is worth noting that this heterogeneous catalyst has high chemical stability and can be recycled for at least five times without reducing its activity. 展开更多
关键词 Heterogeneous catalysis Carbon nitride MOLYBDENUM NITROARENES boronic acids AMINATION
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Room temperature spontaneous surface condensation of boronic acids observed by scanning tunneling microscopy 被引量:1
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作者 Qiu Liang Guangyuan Feng +4 位作者 Hongzhen Ni Yaru Song Xinyu Zhang Shengbin Lei Wenping Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第8期425-428,共4页
Herein,we discovered that the surface-confined condensation of boronic acid can happen spontaneously at room temperature,by comparing the kinetics of condensation of boronic acids with and without the negative sample ... Herein,we discovered that the surface-confined condensation of boronic acid can happen spontaneously at room temperature,by comparing the kinetics of condensation of boronic acids with and without the negative sample bias,we found that the negative sample bias indeed accelerates the self-condensation reaction of boronic acid.Combining with in-situ STM images and ultraviolet photoemission spectrum(UPS)analysis,a reversible adsorption mechanism model was proposed and reasonably explains the reversible electric-field-induced phase transformation. 展开更多
关键词 boronic acids Electric-field-induced condensation Spontaneous condensation Surface-confined synthesis Scanning tunneling microscopy
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Copper-mediated synthesis of N,N'-diarylhydrazines from boronic acids
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作者 Ye Feng Wang Yuan Zhou Jia Rui Wang Lei Liu Qing Xiang Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第5期499-501,共3页
N,N'-Diarylhydrazines have been prepared via the reaction of N-Boc-aryl hydrazines with boronic acids mediated by copper acetate. This mild reaction condition tolerates the presence of a variety of functional groups.
关键词 Cross coupling reaction N N'-Diarylhydrazines boronic acids Copper acetate
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Efficient N-heterocyclic carbene nickel pincer complexes catalyzed cross coupling of benzylic ammonium salts with boronic acids
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作者 Xi-Yu Liu Hai-Bo Zhu +2 位作者 Ya-Jing Shen Jian Jiang Tao Tu 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第2期350-353,共4页
Pyridine-bridged bis-benzimidazolylidene nickel complexes exhibited very high catalytic activity toward cross coupling of inactive(hetero)aryl benzylic ammonium salts with(hetero)aryl and alkenyl boronic acids und... Pyridine-bridged bis-benzimidazolylidene nickel complexes exhibited very high catalytic activity toward cross coupling of inactive(hetero)aryl benzylic ammonium salts with(hetero)aryl and alkenyl boronic acids under mild reaction conditions.Even at 2 mol% catalyst loading,a wide range of substrates for both coupling partners with different steric and electronic properties were well tolerated. 展开更多
关键词 N-Heterocyclic carbene Nickel Cross coupling Benzylic ammonium salts boronic acid
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Highly Efficient Synthesis of Arylpyrrole Derivatives via Rh(lll)-Catalyzed Direct C--H Arylation with Aryl Boronic Acids 被引量:1
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作者 Liang wang Zhan Li +1 位作者 Xing Qu Wangming Peng 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2015年第9期1015-1018,共4页
An efficient and facile method for synthesis of 2-arylpyrroles through Rh(III)-catalyzed direct C--H arylation with pyrrole derivatives and aryl boronic acids has been developed. This reaction could proceed under mi... An efficient and facile method for synthesis of 2-arylpyrroles through Rh(III)-catalyzed direct C--H arylation with pyrrole derivatives and aryl boronic acids has been developed. This reaction could proceed under mild reaction conditions and afford a series of 2-arylated products in good to excellent yields. The gram-scale experiment has been conducted to demonstrate the synthetic potential of this methodology. 展开更多
关键词 rhodium-catalysis C--H arylation arylpyrrole derivatives aryl boronic acids
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Rh(Ⅰ)-Catalyzed Arylation of α-Diazo Phosphonates with Aryl Boronic Acids: Synthesis of Diarylmethylphosphonates
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作者 Yujing Zhou Yan Zhang Jianbo Wang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第5期621-627,共7页
An efficient synthetic method for diarylmethylphosphonates is presented.A series of phosphonate derivatives with diverse functional groups can be accessed via a rhodium catalyzed cross-coupling reaction between a-diaz... An efficient synthetic method for diarylmethylphosphonates is presented.A series of phosphonate derivatives with diverse functional groups can be accessed via a rhodium catalyzed cross-coupling reaction between a-diazo phosphonates and aryl boronic acids.Migratory insertion of rhodium carbene intermediates is postulated to be the critical step in this transformation. 展开更多
关键词 Rh(I)-catalysis metal carbene migratory insertion a-diazo phosphonates aryl boronic acids
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Boronic acid-containing diarylpyrimidine derivatives as novel HIV-1NNRTIs: Design, synthesis and biological evaluation 被引量:2
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作者 Da Feng Fenju Wei +9 位作者 Yanying Sun Prem Prakash Sharma Tao Zhang Hao Lin Brijesh Rathi Erik De Clercq Christophe Pannecouque Dongwei Kang Peng Zhan Xinyong Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第12期4053-4057,共5页
Drug resistance remains to be a serious problem with type Ⅰ human immunodeficiency virus(HIV-1) nonnucleoside reverse transcriptase inhibitors(NNRTIs). A series of novel boronic acid-containing diarylpyrimidine(DAPY)... Drug resistance remains to be a serious problem with type Ⅰ human immunodeficiency virus(HIV-1) nonnucleoside reverse transcriptase inhibitors(NNRTIs). A series of novel boronic acid-containing diarylpyrimidine(DAPY) derivatives were designed via bioisosterism and scaffold-hopping strategies,taking advantage of the ability of a boronic acid group to form multiple hydrogen bonds. The target compounds were synthesized and evaluated for their anti-HIV activities and cytotoxicity in MT-4 cells.Compound 10 j yielded the most potent activity and turned out to be a single-digit nanomolar inhibitor towards the HIV-1 ⅢB [wild-type(WT) strain], L100 I and K103 N strains, with 50% effective concentration(EC_(50)) values of 7.19–9.85 nmol/L. Moreover, 10 j inhibited the double-mutant strain RES056 with an EC_(50) value of 77.9 nmol/L, which was 3.3-more potent than that of EFV(EC_(50)= 260 nmol/L) and comparable to that of ETR(EC_(50)= 32.2 nmol/L). 10j acted like classical NNRTIs with high affinity for WT HIV-1 reverse transcriptase(RT) with 50% inhibition concentration(IC_(50)) value of 0.1837 μmol/L. Furthermore,molecular dynamics simulation indicated that 10 j was proposed as a promising molecule for fighting against HIV-1 infection through inhibiting RT activity. Overall, the results demonstrated that 10 j could serve as a lead molecule for further modification to address virus-drug resistance. 展开更多
关键词 HIV-1 NNRTIS NNIBP DAPY boronic acid Molecular dynamics simulation
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Oriented Antibody Immobilization and Immunoassay Based on Boronic Acid-containing Polymer Brush 被引量:1
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作者 Jie Zhao Ru Mo +4 位作者 Li-Mei Tian Ling-Jie Song Shi-Fang Luan Jing-Hua Yin Lu-Quan Ren 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第4期472-478,共7页
High sensitive immunoassay platforms have gained intense attention due to their vital roles in early-stage disease diagnosis and therapeutic information feedback. Although random covalent-binding of antibody has been ... High sensitive immunoassay platforms have gained intense attention due to their vital roles in early-stage disease diagnosis and therapeutic information feedback. Although random covalent-binding of antibody has been widely adopted in immunoassays due to its simplicity and effectiveness, it readily loses its activity and fails to exhibit high antigen-binding capacity. In this work, copolymer of zwitterionic sulfobetaine methacrylate(SBMA) and glycidyl methacrylate(GMA) brushes were immobilized onto inert polypropylene(PP) via surface-initiated atom transfer radical polymerization(ATRP) based on biomimetic dopamine pretreatment. Subsequently, boronic acid(BA) groups were covalently bonded via active GMA units, followed by the introduction of oriented immobilization of antibody. Owing to the oriented immobilization of antibody facilitated by BA groups in polymer brush, the bioactivity of antibody is well preserved, which endows the surface with significantly enhanced antigen-binding capacity. Moreover, the existence of SBMA segments in polymer brushes renders the surface high resistance to nonspecific protein adsorption, significantly alleviating the signal interference of antigen recognition. This strategy could find potential applications in developing high sensitive immunoassay platforms based on the different substrates. 展开更多
关键词 Biomimetic dopamine Atom transfer radical polymerization (ATRP) boronic acid (BA) IMMUNOASSAY BIOMIMETIC
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One-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide under microwave-assisted conditions 被引量:2
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作者 Yu-Bo Jiang Wen-Sheng Zhang +2 位作者 Hui-Ling Cheng Yu-Qi Liu Rui Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期779-782,共4页
A facile,one-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide has been achieved under microwave-assisted conditions.The reactions can be smoothly completed within... A facile,one-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide has been achieved under microwave-assisted conditions.The reactions can be smoothly completed within a total 10 min through a two-step procedure,including copper-catalyzed coupling of aromatic boronic acids with aqueous ammonia and following propargylation by propargyl bromide. 展开更多
关键词 One-pot Microwave N-Aryl propargylamine Aromatic boronic acid Aqueous ammonia Propargyl bromide
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Synthesis of unnatural N-glycosyl α-amino acids via Petasis reaction 被引量:1
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作者 Chuan-Zhou Tao Zhong-Tang Zhang +2 位作者 Jian-Wei Wu Rong-Hua Li Zhi-Ling Cao 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第4期532-534,共3页
A convenient and efficient protocol for the synthesis of unnatural N-glycosyl cz-amino acids was developed. Condensation of 1,3,4,6-tetra-O-actyl-/%D-glucosamine hydrochloride, alkenyl boronic acid, and glyoxylic acid... A convenient and efficient protocol for the synthesis of unnatural N-glycosyl cz-amino acids was developed. Condensation of 1,3,4,6-tetra-O-actyl-/%D-glucosamine hydrochloride, alkenyl boronic acid, and glyoxylic acid was achieved in CH2C12 to give the derivatives of 2-(N-glycosyl)aminobut-3-enoic acid which may find applications in glycobiology research and medicinal chemistry. 展开更多
关键词 N-'Glycosyl s-amino acid Petasis reaction D-Glucosamine Alkenyl boronic acid
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Boronic acid-containing carbon dots array for sensitive identification of glycoproteins and cancer cells
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作者 Shuai Chen Xuewei Zhang +1 位作者 Yongliang Yu Jianhua Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第10期3043-3047,共5页
Discrimination of glycoproteins and cell types is a significant but difficult issue.Herein,we presented a novel fluorescence sensor array for the detection and identification of glycoproteins and cancer cells based on... Discrimination of glycoproteins and cell types is a significant but difficult issue.Herein,we presented a novel fluorescence sensor array for the detection and identification of glycoproteins and cancer cells based on the specific affinity between boronic acid-containing carbon dots(BA-CDs)and cis-diol residues of polysaccharides.The differential binding affinity of three BA-CDs to various glycoproteins resulted in a different fluorescence turn-on signal pattern caused by aggregation-enhanced emission(AEE),along with negligible response from other proteins.Therefore,BA-CDs encompassing sensing elements and signal indicator into one can enable a fast and accurate discrimination of glycoproteins with simple and easy operation.Seven glycoproteins could be well discriminated at a very low concentration of 10 nmol/L.The discriminating capability of glycoproteins is not sacrificed in both human urine and serum.Notably,different glycoprotein compositions of cancer cells provide more recognizable features for identification of cancer cells,comparing to the total protein.Five cell types could be identified in 15 min at a low concentration of 1000 cells/mL.This method is fast,accurate,and easy operation,and has a potential application in cancer diagnosis. 展开更多
关键词 Sensor array boronic acid Carbon dots Glycoproteins and cells Aggregation-enhanced emission
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A High Sensitive LC-MS/MS Method for the Simultaneous Determination of Potential Genotoxic Impurities Carboxy Phenyl Boronic Acid and Methyl Phenyl Boronic Acid in Lumacaftor
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作者 Kartheek Srinivas Chidella Vijaya Bharathi Dasari A. Jayashree 《American Journal of Analytical Chemistry》 2021年第3期74-86,共13页
A simple, rapid, and highly sensitive LC-MS/MS method has been developed for the simultaneous and trace level quantification of underivatized boronic acids in lumacaftor active pharmaceutical ingredient. Chromatograph... A simple, rapid, and highly sensitive LC-MS/MS method has been developed for the simultaneous and trace level quantification of underivatized boronic acids in lumacaftor active pharmaceutical ingredient. Chromatographic separation of boronic acids and lumacaftor achieved using Agilent Poroshell HPH C18 150<span> </span><span>×</span><span> </span><span>4.6</span><span> </span><span>mm 2.7</span><span> </span><span>μ column with 0.1% ammonia in water as mobile phase A and 100%</span><span> </span><span>acetonitrile as mobile phase B at a flow rate of 0.25</span><span> </span><span>ml/min. Gradient elution</span><span> was</span><span> used with a total method run time of 14</span><span> </span><span>minutes. Boronic acids were successfully ionized and quantified without derivatization using electrospray ionization in negative mode using tandem quadrupole mass spectrometry in multiple reactions monitoring mode. Method validation </span><span>was </span><span>performed as per ICH guidelines with good linearity over the concentration range of 0.05 ppm to 5 ppm of Lumacaftor test concentration for both the boronic acids with a correlation coefficient of >0.99.</span><span> </span><span>Recoveries were found good at different concentration levels and within the range of 80</span><span>% </span><span>-</span><span> </span><span>120%.</span><span> </span><span>The developed method can be successfully used for the routine quantification of boronic acids at a concentration level of 20</span><span> </span><span>ng/ml (1</span><span> </span><span>ppm with respect to 20</span><span> </span><span>mg/ml lumacaftor).</span> 展开更多
关键词 boronic Acid GENOTOXIC LC-MS/MS Lumacaftor
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Mechanism of action of an Ir(Ⅲ) complex bearing a boronic acid active as a H_(2)O_(2)-responsive photosensitizer:ROS generation and quinone methide release for GSH scavenging
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作者 Pierraffaele Barretta Gloria Mazzone 《Inorganic Chemistry Frontiers》 2023年第12期3686-3698,共13页
A DFT-based theoretical investigation is reported here to clarify the mechanism of action of a recently synthesized Ir(Ⅲ)complex,Ir-B(OH)_(2),characterized by the presence of an aryl boronic acid moiety on one bident... A DFT-based theoretical investigation is reported here to clarify the mechanism of action of a recently synthesized Ir(Ⅲ)complex,Ir-B(OH)_(2),characterized by the presence of an aryl boronic acid moiety on one bidentate ligand that can detect H_(2)O_(2) in cancer cells.The H_(2)O_(2)-mediated oxidation of boronic acids under physiological conditions affords the active complex for PDT application,Ir-OH,and a quinone methide(QM)as a by-product,which in turn can scavenge glutathione(GSH)compromising one of the most powerful cellular defence against the ROS produced by PDT treatments.The most plausible reaction mechanism for the oxidation of the aryl boronic acid by H_(2)O_(2) is described.The formation of the products,namely the PS Ir-OH and the QM,is achieved overcoming an energy barrier of 33 kcal mol^(−1) and with a considerable energy gain.The description of the subsequent GSH scavenging mechanism by the released QM evidences that the reaction occurs with a low energy expense.Moreover,the computation of the photophysical properties,needed for evaluating the occurrence of type Ⅰ and type Ⅱ processes,of the prodrug Ir-B(OH)_(2) and the active PS Ir-OH suggests that they are both able to generate the singlet molecular oxygen,^(1)O_(2),while other ROS cannot be achieved.Moreover,the MOs involved in the excited states population,both singlet and triplet,unravel the key role of the metal centre in the ISC process. 展开更多
关键词 aryl boronic acid moiety ir complex h o responsive photosensitizer GSH scavenging ROS generation quinone methide bidentate ligand boronic acids
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Dynamic room-temperature phosphorescence enabled by boronic acid group-mediated 2D perovskite heterojunctions for time-resolved multidimensional anti-counterfeiting and encryption
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作者 Peng Zhang Xin Chen +2 位作者 Jing Li Lei Fang Xiangying Sun 《Inorganic Chemistry Frontiers》 2025年第24期8271-8279,共9页
Dynamic room-temperature phosphorescence(RTP)materials with color-tunable afterglow characteristics hold great promise for advanced anti-counterfeiting and multidimensional encryption applications.In this work,we succ... Dynamic room-temperature phosphorescence(RTP)materials with color-tunable afterglow characteristics hold great promise for advanced anti-counterfeiting and multidimensional encryption applications.In this work,we successfully synthesized a novel two-dimensional phenylammonium cadmium chloride perovskite(B-PACC)with enhanced RTP efficiency via boronic acid group-assisted crystallization.Furthermore,a precise doping strategy was employed to introduce Mn^(2+),which assembled into Mn^(2+)pairs forming a Mn^(2+)-based inorganic layer.This layer,together with B-PACC,constructed a heterojunction structure with different interlayer spacings,enabling dynamic afterglow emission color modulation from red to blue.Moreover,tuning the Mn^(2+)concentration enables precise modulation of the energy transfer rates from the singlet and triplet states of the organic moieties to the Mn^(2+)layer,thereby allowing fine control over the dynamic RTP behavior.Benefiting from the minimal background interference and large chromaticity contrast associated with the red-to-blue phosphorescence transition,the system exhibited high visual detectability.Based on this dynamic afterglow behavior,we successfully developed time-resolved anti-counterfeiting patterns and constructed dynamic room-temperature phosphorescence-based four-dimensional(4D)codes,providing new insights into the design of dynamic RTP materials and highly secure encryption strategies. 展开更多
关键词 chromaticity contrast D perovskite heterojunctions energy transfer color tunable afterglow anti counterfeiting boronic acid group mediated multidimensional codes encryption
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A Cu-based metal-organic framework with two types of connecting nodes as catalyst for oxygen activation
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作者 Zhen Wang Jun-Yu Li +2 位作者 Tao Huang Huai-Ming Li Teng Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第6期463-466,共4页
Using a ditopic organic linker 4-(1H-pyrazol-4-yl)benzoic acid(H_(2)pba),FICN-6,a metal-organic framework containing both Cu_(2)(O_(2)CR)_(4)and Cu_(3)(OH)(pyz)_(3)(O_(2)CR)secondary building units(SBUs),was synthesiz... Using a ditopic organic linker 4-(1H-pyrazol-4-yl)benzoic acid(H_(2)pba),FICN-6,a metal-organic framework containing both Cu_(2)(O_(2)CR)_(4)and Cu_(3)(OH)(pyz)_(3)(O_(2)CR)secondary building units(SBUs),was synthesized.FICN-6 adopts in an unusual intercatenated structure with SBUs from two distinct networks connecting to each other.Presence of Cu_(3)clusters makes FICN-6 a good heterogeneous catalyst for oxygen activation and aerobic oxidative C-C coupling of organic boronic acids. 展开更多
关键词 COPPER Metal-organic framework Oxidative C-C coupling Oxygen activation boronic acids
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Design of a novel mitochondria targetable turn-on fluorescence probe for hydrogen peroxide and its two-photon bioimaging applications 被引量:1
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作者 Kangnan Wang Wen Ma +9 位作者 Yuchun Xu Xin Liu Gui Chen Meng Yu Qiling Pan Chaobo Huang Xiaochuan Li Qingchun Mu Yongbing Sun Zhiqiang Yu 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第12期3149-3152,共4页
Considering that hydrogen peroxide(H2O2)plays significant roles in oxidative stress,the cellular signal transduction and essential biological process regulation,the detection and imaging of H2O2 in living systems unde... Considering that hydrogen peroxide(H2O2)plays significant roles in oxidative stress,the cellular signal transduction and essential biological process regulation,the detection and imaging of H2O2 in living systems undertakes critical responsibility.Herein,we have developed a novel two-photon fluorescence turn on probe,named as Pyp-B for mitochondria H2O2 detection in living systems.Selectivity studies show that probe Pyp-B exhibit highly sensitive response toward H2O2 than other reactive oxygen species(ROS)and reactive nitrogen species(RNS)as well as biologically relevant species.The fluorescence colocalization studies demonstrate that the probe can localize in the mitochondria solely.Furthermore,as a bio-compatibility molecule,the highly selective and sensitive of fluorescence probe Pyp-B have been confirmed by its cell imaging application of H2O2 in living A549 cells and zebrafishes under the physiological conditions. 展开更多
关键词 Hydrogen peroxide detection p-Phenyl boronic acid ester Mitochondria target Two-photon fluorescence BIOIMAGING
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Synthesis and Single Crystal X-ray Studies of 3-(3,5-Bis(trifluoromethyl)phenyl) Quinoline and 3-(4-Fluoro-3-methylphenyl) Quinoline 被引量:1
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作者 Malik Aman Ullah Muhammad Adeel +2 位作者 Muhammad Nawaz Tahir Muhammad Raza Shah Irfan Ullah 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第1期90-96,共7页
The title compounds 3-(3,5-bis(trifluoromethyl)phenyl)quinoline (1) and 3-(4- fluoro-3-methylphenyl)quinoline (2) were synthesized through Suzuki-Miyaura Cross coupling reaction of 3-bromoquinoloine with ary... The title compounds 3-(3,5-bis(trifluoromethyl)phenyl)quinoline (1) and 3-(4- fluoro-3-methylphenyl)quinoline (2) were synthesized through Suzuki-Miyaura Cross coupling reaction of 3-bromoquinoloine with aryl boronic acids. The title compounds were characterized by single-crystal X-ray diffraction, 1H NMR, 13C NMR, El-MS, elemental analysis and IR. The crystals of 3-(3,5-bis(trifluoromethyl)phenyl)quinoline (C17H9F6N, Mr = 341.25) belongs to the monoclinic system, space group P21n, a = 12.3072(13), b = 4.9378(6), c = 24.493(2) A, V= 1473.1(3) A3, Z = 4, Dc = 1.539 Mg m-3, 2 - 0.71073A, μ = 0.144 mm^-1, F(000) = 688, the final R = 0.0715 and wR = 0.1873 for 1875 obserwed reflections with I 〉 2σ(I) and the crystal of 3-(4-fluoro-3- methylphenyl)quinoline (C16H12FN, Mr= 237.27) belongs to the orthorhombic system, space group Pca21, a = 23.794(2), b = 3.9094(3), c = 25.669(2) A, V = 2387.7(4) A3, Z = 8, D, = 1.320 Mg m-3, 2 = 0.71073 A, μ = 0.088 mm-1, F(000) = 992, the final R = 0.0534 and wR = 0.1188 for 2270 observed reflections with I 〉 2σ(I). 展开更多
关键词 3-bromoquinoline crystal structure Pd(PPh3)3 boronic acid suzuki coupling
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Tribological behavior of hot-pressed boron carbide with oxidation 被引量:1
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作者 WANG Ling sen,WU Fang,ZHANG Jin sheng,FAN Yi,LIU Bo wei,GAO You (State Key Laboratory for Powder Metallurgy, Central South University, Changsha 410083, China) 《Journal of Central South University of Technology》 EI 2001年第2期89-93,共5页
The oxidation behavior at 973 1 273 K and the effect of oxidation on the room temperature tribological properties of hot pressed boron carbide ceramic were investigated. Oxidized samples were studied by X ray diffract... The oxidation behavior at 973 1 273 K and the effect of oxidation on the room temperature tribological properties of hot pressed boron carbide ceramic were investigated. Oxidized samples were studied by X ray diffractometer and scanning electron microscopy. It is demonstrated that the oxidation results in the formation of a thin transparent B 2O 3 film, and the oxide film is severely cracked during cooling due to the thermal expansion mismatch between the oxide film and B 4C substrate. B 2O 3 reacts with moisture in air to form boric acid, which is a kind of solid lubricant. The sliding friction factors of oxidized B 4C pair are about 0.05 0.08, compared to 0.25 0.35 of the as received B 4C pair. When the oxidation temperature is up to 1 273 K, severe unstability and increase of friction factor are observed. Visual inspection of the wear track reveals that the lubricant film is broken and some debris particles occur on and around the rubbing surfaces, because the friction interface is rough by the severe etching of grain boundaries. 展开更多
关键词 OXIDATION boron carbide friction factor boron oxide boron acid
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Quantitative detection of citrate for early stage diagnosing of prostate cancer:Discriminating normal to cancer in prostate tissues
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作者 Selvaraj Muthusamy Kanagaraj Rajalakshmi +7 位作者 Palanisamy Kannan Yun-Sik Nam Dongwei Zhu Yeonggil Seo Jong-Won Song Dong Nyoung Heo Il Keun Kwon Yuanguo Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第2期501-506,共6页
Prostate cancer(PC)biomarker-citrate detection is clinically important to diagnose PC in early stages.Methylquinolinium iodide(Q)conjugated indole-phenylboronic acid(IB)was designed as a red-emissive QIB probe for the... Prostate cancer(PC)biomarker-citrate detection is clinically important to diagnose PC in early stages.Methylquinolinium iodide(Q)conjugated indole-phenylboronic acid(IB)was designed as a red-emissive QIB probe for the detection of citrate through Lewis acid-base reaction and intramolecular charge transfer(ICT)sensing mechanisms.Boronic acid acts as Lewis acid as well as citrate(Lewis base)recognition unit.The probe reacted with citrate,showing enhanced red emissions.Since the probe has excellent water solubility and great biocompatibility,practical application in biological systems is possible.Citrate was monitored precisely in the mitochondria organelle(in vitro)of living cells with a positive charge on QIB.Also,endogenous(in situ)citrate was detected quantitatively to discriminate non-cancerous and PC mice,observed strong and lower(negligible)emission intensity on non-cancerous and cancerous prostate tissues,respectively.Because,the concentration of citrate is higher in healthy prostate compared with PC prostate.Furthermore,the analysis of sliced prostate tissues can give PC-related information for clinical diagnosis to prevent and treat PC in the initial stages.Therefore,we believe that the present probe is a promising biochemical reagent in diagnosing PC. 展开更多
关键词 Prostate cancer Biomarker-citrate boronic acid Lewis acid/base-ICT Red-emissive Mitochondria targeting Prostate tissue
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Cu2O-Mediated Room Temperature Cyanation of Aryl Boronic Acids/Esters and TMSCN
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作者 Yong Ye Yanhua Wang +1 位作者 Pengtang Liu Fushe Han 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第1期27-30,共4页
A method for the efficient and reliable synthesis of aryl nitriles via the Cu20-catalyed cross-coupling of aryl boronic acids or esters and TMSCN is presented. A broad range of substrates decorated by electron-rich an... A method for the efficient and reliable synthesis of aryl nitriles via the Cu20-catalyed cross-coupling of aryl boronic acids or esters and TMSCN is presented. A broad range of substrates decorated by electron-rich and defi- cient, sterically very congested, and labile functionalities were tolerated. Moreover, the reaction can proceed under mild conditions at room temperature. These advantages paired with the use of cheap, readily available, and halo- gen-free Cu20 as catalysts make the protocol an appealing option for aryl cyanations. 展开更多
关键词 copper boronic acid boronic ester CYANATION aryl nitrile
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