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A novel synthesis of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction in ionic liquid 被引量:3
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作者 Xin Ying Zhang Xiao Yan Li Xue Sen Fan Xia Wang Jian Ji Wang Gui Rong Qu 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期153-156,共4页
An efficient and novel procedure for the preparation of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction of aldehyde, 5-amino-3-methyl-1-phenylpyrazole and malononitrile or cyanoacetate in [bmim][B... An efficient and novel procedure for the preparation of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction of aldehyde, 5-amino-3-methyl-1-phenylpyrazole and malononitrile or cyanoacetate in [bmim][BF4] is described in this paper. Advantages of the method presented here include mild conditions, high yields together with a green nature and ease of recovery and reuse of the reaction medium. 展开更多
关键词 Pyrazolo[3 4-b]pyridine Multi-component reaction Ionic liquid
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Synthesis, Reactions and Characterization of 1,1’-(1,4-Phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(ethan-1-one)
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作者 Ahmed A. M. Elreedy Hameed M. Alkubaisi Fawzy A. Attaby 《International Journal of Organic Chemistry》 CAS 2016年第1期65-76,共12页
Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). Th... Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). The reaction of 2 with hydrazine hydrate followed by diazotization reaction af-forded the 1,1’-(1,4-phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(e-than-1-one) (3) and 1,1’-(1,4-phenylenebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3,4-b]-pyridine-4,5-diyl))bis(ethan-1-one) (4) respectively. On the other hand, reaction of 4 with malononitrile, 2-cyanoethanethioamide, ethyl acetoacetate, acetyl acetone, ethyl benzoylacetate, diethylmalonate, ethyl cyanoacetate and phenacylbromide aiming to build up pyrazolotriazine or pyrazole ring on the ring system of 4. Structures of all newly synthesized heterocyclic compounds in the present study were confirmed by considering the data of IR, 1H NMR, mass spectra as well as that of elemental analyses. 展开更多
关键词 Bis-1 2-dihydropyridine-3-carbonitrile Bis-Nicotinonitrile 1 1’-(1 4-Phenyl-enebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3 4-b]pyri-dine-4 5-diyl))bis(ethan-1-one) Bis-dihydropyrido[2’ 3’:3 4]pyrazolo[5 1-c][1 2 4]triazine-3-carboxylate Bis-1H-pyrazolo[3 4-b]pyridine
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Catalyst free synthesis of fused pyrido[2,3-d]pyrimidines and pyrazolo[3,4-b]pyridines in water 被引量:1
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作者 Abbas Rahmati Zahra Khalesi 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第10期1149-1152,共4页
A one-pot, three-component condensation reaction of an aldehyde, benzoyl acetonitrile (3-oxo-3-phenylpropane nitrile) and 6- amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione or 3-methyl-l-phenyl-lH-pyrazol-5-amine in... A one-pot, three-component condensation reaction of an aldehyde, benzoyl acetonitrile (3-oxo-3-phenylpropane nitrile) and 6- amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione or 3-methyl-l-phenyl-lH-pyrazol-5-amine in water to give fused pyrido[2,3- d]pyrimidines and pyrazolo[3,4-b]pyridines in high yields without any catalyst, is described. 展开更多
关键词 AMINOPYRAZOLE Aqueous media 3-Methyl-l-phenyl-lH-pyrazol-5-amine Pyrazolo[3 4-b]pyridine
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Pulmonary Edema and Pleural Effusion Detection Using Efficient Net-V1-B4 Architecture and AdamW Optimizer from Chest X-Rays Images
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作者 Anas AbuKaraki Tawfi Alrawashdeh +4 位作者 Sumaya Abusaleh Malek Zakarya Alksasbeh Bilal Alqudah Khalid Alemerien Hamzah Alshamaseen 《Computers, Materials & Continua》 SCIE EI 2024年第7期1055-1073,共19页
This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was f... This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was formed by combining 28,309 samples from the ChestX-ray14,PadChest,and CheXpert databases,with 10,287,6022,and 12,000 samples representing Pleural Effusion,Pulmonary Edema,and Normal cases,respectively.Consequently,the preprocessing step involves applying the Contrast Limited Adaptive Histogram Equalization(CLAHE)method to boost the local contrast of the X-ray samples,then resizing the images to 380×380 dimensions,followed by using the data augmentation technique.The classification task employs a deep learning model based on the EfficientNet-V1-B4 architecture and is trained using the AdamW optimizer.The proposed multiclass system achieved an accuracy(ACC)of 98.3%,recall of 98.3%,precision of 98.7%,and F1-score of 98.7%.Moreover,the robustness of the model was revealed by the Receiver Operating Characteristic(ROC)analysis,which demonstrated an Area Under the Curve(AUC)of 1.00 for edema and normal cases and 0.99 for effusion.The experimental results demonstrate the superiority of the proposedmulti-class system,which has the potential to assist clinicians in timely and accurate diagnosis,leading to improved patient outcomes.Notably,ablation-CAM visualization at the last convolutional layer portrayed further enhanced diagnostic capabilities with heat maps on X-ray images,which will aid clinicians in interpreting and localizing abnormalities more effectively. 展开更多
关键词 Image classification decision support system EfficientNet-V1-b4 AdamW optimizer pulmonary edema pleural effusion chest X-rays
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Selective Synthesis of 1,2-Diarylpyrrolo[3,4-b]pyridine-5,7- diones via Cyclization Reaction of β-Enamino Imides with Cinnamaldehydes
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作者 Yanhong Jiang Chaoguo Yan 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2016年第12期1255-1262,共8页
The novel 1,2-diaryl substituted pyrrolo[3,4-b]pyridine-5,7-diones were selectively synthesized in high yields by the base catalyzed cyclization reaction of 3-arylamino-l-methyl-lH-pyrrole-2,5-diones with cinnamaldehy... The novel 1,2-diaryl substituted pyrrolo[3,4-b]pyridine-5,7-diones were selectively synthesized in high yields by the base catalyzed cyclization reaction of 3-arylamino-l-methyl-lH-pyrrole-2,5-diones with cinnamaldehyde and its derivatives in acetonitrile at room temperature. However, when piperidinium trifluoroacetate was employed as catalyst, the reaction afforded a mixture of 1,2-diaryl and 1,4-diaryl substituted pyrrolo[3,4-b]pyridine-5,7-diones in comparable yields. 展开更多
关键词 pyrrolo[3 4-b]pyridine 1 2-dihydropyridine 1 4-DIHYDROpyridine β-enamino amide CINNAMALDEHYDE
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Microwave-induced Stereoselectivity in Synthesis of trans-4-Aryl-3-methyl-6-oxo-4,5,6,7-tetrahydro-2H- pyrazolo[3,4-b]pyridine-5-carbonitriles
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作者 Rahmati, Abbas Alizadeh Kouzehrash, Meysam 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第11期2373-2378,共6页
A facile synthesis of trans isomers of 4-aryl-3-methyl-6-oxo-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine-5- carbonitriles via three-component condensation reaction of an aldehyde, 3-amino-5-methylpyrazole and ethyl ... A facile synthesis of trans isomers of 4-aryl-3-methyl-6-oxo-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine-5- carbonitriles via three-component condensation reaction of an aldehyde, 3-amino-5-methylpyrazole and ethyl cyanoacetate in acetonitrile has been developed under microwave irradiation. This one-pot reaction proceeds with-out any catalyst in short times and gives the product in high selectivities and high yields. 展开更多
关键词 multi-component condensation reactions microwave pyrazolo[3 4-b]pyridine 3-amino-5- methylpyrazole
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Synthesis of Certain 3-Aminopyrazolo[5,4-b]pyridine and 3,4-Substituted Pyrido[2′,3′:3,4]pyrazolo[5,1-c][1,2,4]triazine Derivatives
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作者 EL-LOUH, Ali Khader Khalil ABUNADA, Nada Mohamed EL-SHOUBAKI, Mohamed 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第12期1887-1891,共5页
2-Thioxo-1,2-dihydropyridine derivatives 2a, 2b were reacted with methyl iodide to give 2-methylthiopyridines 3a, 3b, which were reacted with hydrazine hydrate to produce 3-aminopyrazolo[5,4-b]pyridines 4a, 4b. Compou... 2-Thioxo-1,2-dihydropyridine derivatives 2a, 2b were reacted with methyl iodide to give 2-methylthiopyridines 3a, 3b, which were reacted with hydrazine hydrate to produce 3-aminopyrazolo[5,4-b]pyridines 4a, 4b. Compounds 4a, 4b were diazotized to afford the corresponding diazonium salts 5a, 5b, which were reacted with some active methylene compounds 6a-6h to give the corresponding pyrido[2′,3′ : 3,4]pyrazole[5,1-c][1,2,4]triazines 7-14. 展开更多
关键词 pyrazolo[3 4-b]pyridine pyrido[2′ 3′ 3 4]pyrazole[5 1-c] [ 1 2 4]triazine 2-arylmethylidene-2-cyanothioacetamine 2-thioxopyridine
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Synthesis of derivatives of imidazo[4,5-b]pyridine:Novel sulfur contained side chains for macrolide antibiotics 被引量:2
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作者 Lu Liu Peng Xu Liang Zhou Ping Sheng Lei 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第1期1-4,共4页
Two series of novel derivatives of imidazo[4,5-b]pyridine were synthesized. These compounds could be used as side chains of semisynthesised ketolide antibiotics. The side chains have free amine group which can attache... Two series of novel derivatives of imidazo[4,5-b]pyridine were synthesized. These compounds could be used as side chains of semisynthesised ketolide antibiotics. The side chains have free amine group which can attached to ketolide core. Macrolides with this kind of side chains will show obvious activities against erythromycin-resistant strains. The structure of the side chains was confirmed by ^1H, ^13C NMR, MS, HMBC spectra. 2007 Ping Sheng Lei. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 MACROLIDE Heterarylalkyl sulfur contained side chain Imidazo[4 5-b]pyridine Synthesis HMBC
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A New Diiminopyridyl Cobalt Complex [CoCl_2L](L=2,6-Bis(N,N'-bis(2,6-diisopropyl-4-(2,3-dimethyoxylbenzoylamide)phenylimino))pyridine)
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作者 龙泽荣 赵启龙 +2 位作者 李少光 夏娅娜 吴彪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期869-874,共6页
The reaction of CoCl2·6H2O with 2,6-bis(N,N'-bis(2,6-diisopropyl-4-(2,3-dimethy-oxyl-benzoylamide)phenylimino))pyridine(L) afforded the complex [CoCl2L],which was fully characterized by elemental analysi... The reaction of CoCl2·6H2O with 2,6-bis(N,N'-bis(2,6-diisopropyl-4-(2,3-dimethy-oxyl-benzoylamide)phenylimino))pyridine(L) afforded the complex [CoCl2L],which was fully characterized by elemental analysis,UV-vis,IR spectroscopy,fluorescence,and X-ray diffraction analysis.The compound is of triclinic system,space group P1 with a = 13.058(3),b = 13.798(3),c = 16.695(3) ,α = 98.191(3),β = 102.792(3),γ = 101.820(3)°,V = 2815.0(9) 3,Z = 2,F(000) = 1122,μ = 0.45 mm-1,R = 0.061 and wR = 0.1349 for 9842 observed reflections(Ⅰ 〉 2σ(Ⅰ)).The Co(Ⅱ) center adopts a distorted square-pyramidal coordination geometry.The extended structure shows a one-dimensional zigzag double chain linked by hydrogen bonds and π-π stacking interactions. 展开更多
关键词 2 6-bis(N N'-bis(2 6-diisopropyl-4-(2 3-dimethyoxylbenzoylamide)phenylimino)) pyridine cobalt crystal structure fluorescence
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New and Facile Synthesis of Substituted Pyrrole, Pyridine, Pyrazolo[4,3-b] Pyridine, Pyrano[3,2-c] Quinoline, Napthopyran, Naphthodipyran and Coumarin Derivatives
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作者 F. M. A. El-Taweel A. A. Elagamey 《International Journal of Organic Chemistry》 2013年第1期58-70,共13页
Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14.... Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14. Pyrano[3,2-c] quinolines 20a, b and 23 were obtained by reacting 4-hydroxyquinoline 15 with 1g, h, 2b respectively. Reaction of 1 with naphthalenediols 24, 27 and 29 yield naphthodipyrans 26a, b, 28a, b and 30a。 展开更多
关键词 PYRROLE pyridine Pyrazolo[4 3-b] pyridine Pyrano[3 2-c] QUINOLINE NAPHTHOPYRAN Naphthodipyrans and Coumarin
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Theoretical Study on the Reaction Mechanism of 2-Methoxybenzaldehyde,4-Bromo-indanone,Malononitrile and Ammonium Acetate One-pot to Form 6-(2-Methoxyphenyl)-2-amino-6-bromo-5H-indeno[1,2-b]pyridine-3-carbonitrile
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作者 张福兰 黄辉胜 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第10期1685-1696,共12页
The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by densit... The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results. 展开更多
关键词 2-methoxybenzaldehyde 4-bromo-indanone 6-(2-methoxyphenyl)-2-amino-6-bromo-5H-indeno[1 2-b]pyridine-3-carbonitrile density functional reaction mechanism
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Crystal Structure of Poly[(2,6-di(2’,4’-dicarboxylphenyl)pyridine-κ4 O:O′:O″:O′′′)-(μ2-1,4-bis(1-imidazolyl)benzene-κ2N:N’)cobalt(II)],C_(39)H_(24)Co_(2)N_(7)O_(8)
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作者 Wang Yenan Liu Bo Niu Xiaoqing 《Plant Diseases and Pests》 CAS 2021年第1期38-43,共6页
[Objective]The paper was to synthesize a new structure of metal organic framework,and to provide new materials for plant pathogens testing.[Method]A mixture of 2,6-di(2’,4’-di-carboxylphenyl)pyridine,1,4-bis(1-imida... [Objective]The paper was to synthesize a new structure of metal organic framework,and to provide new materials for plant pathogens testing.[Method]A mixture of 2,6-di(2’,4’-di-carboxylphenyl)pyridine,1,4-bis(1-imidazolyl)benzene,Co(NO_(3))2·6H_(2)O were added to the solution of DMF:H2O=3:3 and heated at 433K for 4 d.[Result]Red crystals of the title compound were obtained(yield 76.3%,based on Co).[Conclusion]The crystal data were obtained as follows:C_(39)H_(24)Co_(2)N_(7)O_(8),monoclinic,P21/c,a=16.222(7)A,b=12.653(5)A,c=17.456(7)A,β=102.386(6)°,V=3500(2)A_(3),Z=4,Rgt(F)=0.0550,wRref(F2)=0.1509,T=293(2)K. 展开更多
关键词 Poly[(2 6-di(2’ 4’-dicarboxylphenyl)pyridine Cobalt(II)
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黄芩素抑制Toll样受体4/核因子-B炎症通路改善小鼠脑出血后脑损伤的作用及机制研究 被引量:2
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作者 王春喜 余永佳 +1 位作者 黄立添 冯大勤 《现代实用医学》 2023年第7期844-848,F0003,共6页
目的 探讨黄芩素抑制Toll样受体4(TLR4)/核因子-κB(NF-κB)炎症通路改善小鼠脑出血后脑损伤的作用及机制研究。方法 通过胶原酶注射小鼠右侧基底节区诱导小鼠脑出血,模型模型诱导后小鼠腹腔注射不同剂量黄芩素或者同体积溶剂,并通过神... 目的 探讨黄芩素抑制Toll样受体4(TLR4)/核因子-κB(NF-κB)炎症通路改善小鼠脑出血后脑损伤的作用及机制研究。方法 通过胶原酶注射小鼠右侧基底节区诱导小鼠脑出血,模型模型诱导后小鼠腹腔注射不同剂量黄芩素或者同体积溶剂,并通过神经功能学评分及脑水含量分析其保护作用;通过不同时间点给药(模型诱导后6及12h),评估黄芩素治疗时间窗;对TLR4和NF-κB信号通路的变化、小胶质细胞活化及神经细胞退变(FJC)进行检测。结果 黄芩素可减轻脑出血后脑水含量并改善神经功能学评分,并且模型诱导后6 h开始治疗,仍然有效;黄芩素可减少脑出血后神经细胞变性;黄芩素通过抑制小胶质细胞活化及TLR4/NF-κB通路及其下游促炎因子(TNF-α及IL-1β)的产生发挥抗炎作用。结论 黄芩素在脑出血后通过抗细胞死亡和抗炎作用发挥神经保护作用。 展开更多
关键词 脑出血 脑损伤 黄芩素 炎症 TOLL样受体4 核因子-b
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Studies on the Synthesis of Pyridine Analogs of the Natural Product3,5,4'-Trimethoxystilbene 被引量:2
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作者 Zhi Song PIAO Lin WANG Zhi Zhong ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1119-1122,共4页
Five pyridine analogs of the natural product, 3, 5, 4'-trimethoxystilbene, were synthesized. The final compounds were characterized by 1H-NMR.
关键词 SYNTHESIS pyridine analogs of 3 5 4'-trimethoxystilbene .
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佛手多糖对1-甲基-4-苯基-吡啶离子诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用研究
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作者 陈进炫 龚舒 +3 位作者 刘天开 龚记熠 乙引 刘文华 《食品与发酵工业》 CAS CSCD 北大核心 2024年第8期17-23,共7页
该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s dis... 该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s disease,PD)细胞模型,实验分为对照组、MPP+模型组、佛手多糖组。采用噻唑蓝(methye thiazdye telrazlium,MTT)法检测细胞存活率,Hoechst33258染色法观察细胞形态,2′,7′-二氯荧光黄双乙酸盐荧光探针检测细胞活性氧(reactive oxygen species,ROS)水平,JC-1荧光探针法检测线粒体膜电位,蛋白免疫印迹(Western blot)检测磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)、蛋白激酶B(protein kinase B,Akt)、磷酸化细胞外调节蛋白激酶(phosphorylated extracellular regulated protein kinases1/2,p-ERK1/2)和细胞色素c(cytochrome c,Cyt-c)蛋白表达水平。结果表明,佛手多糖的得率4.86%,纯度为44.46%,经过AB-8纯化后,纯度提高到60.81%;与对照组相比,模型组细胞的存活率显著降低,Hoechst33258染色下可见细胞破碎,细胞核皱缩,细胞内ROS显著增加,线粒体膜电位显著降低。与模型组相比,佛手多糖组的细胞存活率显著增加,细胞形态明显得到改善,ROS水平下降,线粒体膜电位升高。Western blot结果显示,佛手多糖能抑制MPP+引起的p-Akt和p-ERK1/2的降低,以及Cyt-c的上升。综上,佛手多糖对MPP+诱导SH-SY5Y细胞损伤具有保护作用,其机制可能是通过调节线粒体ROS的产生和Cyt-c的释放,进而维持线粒体稳态,激活Akt信号通路和ERK信号通路,抑制细胞的凋亡,从而起到保护作用。研究结果可为缓解帕金森病的发生发展提供理论依据,同时也能更好地开发和利用佛手资源。 展开更多
关键词 佛手多糖 提取纯化 MPP+ SH-SY5Y细胞 保护作用
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ZnO/g-C_(3)N_(4)异质结光催化材料的制备及对吡啶的降解 被引量:2
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作者 唐贝 《无机盐工业》 CAS CSCD 北大核心 2024年第4期133-142,共10页
采用蒸发溶剂-高温热聚合法制备了ZnO/g-C_(3)N_(4)异质结光催化材料,采用XRD、FTIR、TEM、XPS、UV-vis DRS、PL、TPC和EIS等表征技术对其进行了详细系统的表征,评价了ZnO/g-C_(3)N_(4)光催化降解吡啶的活性和稳定性,采用L_(9)(3^(4))... 采用蒸发溶剂-高温热聚合法制备了ZnO/g-C_(3)N_(4)异质结光催化材料,采用XRD、FTIR、TEM、XPS、UV-vis DRS、PL、TPC和EIS等表征技术对其进行了详细系统的表征,评价了ZnO/g-C_(3)N_(4)光催化降解吡啶的活性和稳定性,采用L_(9)(3^(4))正交实验考察了不同因素对光催化性能的影响,并对光催化机理进行了探讨。XPS和TEM结果证明了ZnO和g-C_(3)N_(4)之间异质结的形成,异质结的形成有效促进了光电子-空穴的分离,提高了光吸收,拓宽了光谱范围。在ZnO/g-C_(3)N_(4)复合光催化剂投加量为50 mg、ZnO与g-C_(3)N_(4)质量比为1∶2、吡啶初始质量浓度为20 mg/L和体系p H为7.0的条件下,可见光照射60 min后ZnO/g-C_(3)N_(4)对吡啶的光催化降解率达到了98.9%,循环使用5次后光催化降解率为97.3%,具有良好的稳定性。ZnO/g-C_(3)N_(4)光催化降解吡啶主要依赖于活性基团超氧自由基(·O_(2)^(-))和空穴(h^(+))的作用。 展开更多
关键词 ZnO/g-C_(3)N_(4) 光催化 异质结 吡啶
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Synthesis,Crystal Structure,DFT Studies and Biological Activity of a Novel Schiff Base Containing Triazolo[4,3-a]pyridine Moiety 被引量:5
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作者 沈钟华 石延霞 +6 位作者 杨明艳 孙召慧 翁建全 谭成侠 刘幸海 李宝聚 赵卫光 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第3期457-464,共8页
The novel Schiff base(E)-8-chloro-NA-(4-(dimethylamino)benzylidene)-[1,2,4]triazolo[4,3-a]pyridine-3-carbohydrazide was synthesized and characterized by ^1H NMR,MS,elemental analysis and X-ray diffraction.The co... The novel Schiff base(E)-8-chloro-NA-(4-(dimethylamino)benzylidene)-[1,2,4]triazolo[4,3-a]pyridine-3-carbohydrazide was synthesized and characterized by ^1H NMR,MS,elemental analysis and X-ray diffraction.The compound crystallizes in the monoclinic space group P2_1/c with a = 7.091(2),b = 10.750(3),c = 21.380(6) A,β = 96.299(6)°,V = 1619.7(8) A^3,Z = 4 and R = 0.0351.Theoretical calculation of the title compound was carried out with the B3LYP/6-31 G basis set.The frontier orbital energy and atomic net charges were discussed.It is found that the experimental data show good agreement with the calculated values.And the compound exhibits good antifungal activity against Stemphylium lycopersici(Enjoji) Yamamoto. 展开更多
关键词 1 2 4-triazolo[4 3-a]pyridine hydrazine synthesis crystal structure theoretical calculation antifungal activity
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Preparation and Electrochemical Properties of 3-Pyridinyl-6-aryl-1,2,4-triazolo [3,4-b][1, 3,4]thiadiazoles 被引量:3
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作者 TaiXIAO HuiXueLI +1 位作者 ChunXiaTAN MiaoCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期335-337,共3页
A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all ... A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all these compounds have a higher electron affinity (EA) than 2-(4-biphenyl)-5-(4-tert-butyl phenyl)-1, 3, 4-oxadiazole (PBD) which implies that PATT could be acting as better electron acceptors than widely used electron transporting material PBD. 展开更多
关键词 PREPARATION 3-pyridinyl-6-aryl-1 2 4-triazolo[3 4-b][1. 3 4]thiadiazoles electro- chemical properties.
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A New Zn(Ⅱ) Coordination Polymer Constructed from 4-(1H-pyrazol-3-yl)pyridine as Fluorescent Sensor for Fe^(3+) 被引量:1
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作者 LIU Na XING Guang-En +1 位作者 HUANG Xiao-Xiao GUO Jing 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第4期660-666,共7页
A new Zn(Ⅱ) coordination polymer, [Zn(4-PP)(1,4-BDC)?(H_2O)]_n(1, 4-PP = 4-(1 H-pyrazol-3-yl)pyridine, 1,4-H_2BDC = 1,4-benzenedicarboxylic acid), has been synthesized and structurally characterized by single-crystal... A new Zn(Ⅱ) coordination polymer, [Zn(4-PP)(1,4-BDC)?(H_2O)]_n(1, 4-PP = 4-(1 H-pyrazol-3-yl)pyridine, 1,4-H_2BDC = 1,4-benzenedicarboxylic acid), has been synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis, IR spectra, XRPD and TG. Structural analysis reveals that Zn(Ⅱ) ions are bridged by COO-from 1,4-BDC^(2-)to form a binuclear structure as the second building units(SBUs). Zn_2 clusters can be clarified as 4-connected nodes, so the framework of 1 can be considered as a 2 D(44?62)-sql sheet. Fluorescence measurements show that 1 has highly selective and sensitive detection of Fe^(3+) in water medium. 展开更多
关键词 4-(1H-pyrazol-3-yl)pyridine crystal structure LUMINESCENCE sensor zinc complex
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Synthesis,Crystal Structure and Antifungal Activity of 8-Chloro-3-((4-chlorobenzyl)-thio)[1,2,4]triazolo[4,3-a]pyridine 被引量:2
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作者 汪乔 翟志文 +3 位作者 孙召慧 刘幸海 谭成侠 翁建全 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第4期651-655,共5页
The title compound 8-chloro-3-((4-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine was prepared from 1-chloro-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence o... The title compound 8-chloro-3-((4-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine was prepared from 1-chloro-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence of Na OH, and its structure was determined by X-ray diffraction analysis. The crystal is of triclinic system, space group P1 with a = 6.8264(6), b = 7.5890(4), c = 13.0960(7) A, α = 93.447(4), β = 98.772(6), γ = 92.615(6)o, V = 668.26(8) A3, Z = 2, the final R = 0.035 and wR = 0.09 for 2259 observed reflections with I 〉 2σ(I). The preliminary biological test showed that the title compound has activities against Stemphylium lycopersici(Enjoji) Yamamoto, Fusarium oxysporum. sp. cucumebrium, and Botrytis cinerea with inhibitory to be 51.19%, 62.02% and 15.56%, respectively. 展开更多
关键词 1 2 4-triazolo[4 3-a]pyridine synthesis crystal structure antifungal activity
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