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Effect of Excited-state Substituent Constant on the UV Spectra of 1,4-disubstituted Benzenes 被引量:9
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作者 陈冠凡 曹晨忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期366-370,447,共6页
A correlation equation between the UV absorption wavenumbers of 1,4-disubstituted benzenes and the excited-state substituent constant was obtained. For 80 sorts of 1,4- disubstituted benzenes, the correlation coeffici... A correlation equation between the UV absorption wavenumbers of 1,4-disubstituted benzenes and the excited-state substituent constant was obtained. For 80 sorts of 1,4- disubstituted benzenes, the correlation coefficient was 0.9805, and the standard deviation was only 672.27 cm^-1. The results imply that the excited-state substituent constant can be used productively for research on UV energy of 1,4-disubstituted benzenes. The present method provides a new avenue to study the UV absorption spectra of aromatic systems with the excited-state substituent constant, and it is helpful to understand the effect of substituent electrostatic effects on the chemical and physical properties of conjugated compounds with multiple substituents in excited state. 展开更多
关键词 Excited-state substituent constant 1 4-disubstituted benzene UV absorption wavenumber Interaction of substituent
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H_(4)SiW_(12)O_(40)-catalyzed cyclization of epoxides/aldehydes and sulfonyl hydrazides: An efficient synthesis of 3,4-disubstituted 1H-pyrazoles 被引量:1
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作者 Guoping Yang Xuanjie Xie +5 位作者 Mengyuan Cheng Xiaofei Gao Xiaoling Lin Ke Li Yuanyuan Cheng Yufeng Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第3期1483-1487,共5页
A simple and efficient method for the synthesis of pyrazoles through a silicotungstic acid (H_(4)SiW_(12)O_(40))-catalyzed cyclization of epoxides/aldehydes and sulfonyl hydrazides has been developed. Various epoxides... A simple and efficient method for the synthesis of pyrazoles through a silicotungstic acid (H_(4)SiW_(12)O_(40))-catalyzed cyclization of epoxides/aldehydes and sulfonyl hydrazides has been developed. Various epoxides/aldehydes were smoothly reacted with sulfonyl hydrazides to furnish regioselectivity 3,4-disubstituted 1H-pyrazoles. The application of such an earth-abundant, readily accessible, and nontoxic catalyst provides a green approach for the construction of 3,4-disubstituted 1H-pyrazoles. A plausible reaction mechanism has been proposed on the basis of control experiments, GC-MS and DFT calculations. 展开更多
关键词 Silicotungstic acid EPOXIDES ALDEHYDES Sulfonyl hydrazides 3 4-disubstituted 1H-pyrazoles
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One-pot synthesis of 1,4-disubstituted 1,2,3-triazoles from nitrobenzenes
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作者 Fen Zhao Zhen Chen +2 位作者 Kai Xie Rui Yang Yu-Bo Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第1期109-113,共5页
A facile synthesis of 1,4-disubstituted 1,2,3-triazoles was achieved from nitrobenzenes and terminal alkynes under mild conditions. The reactions were successful for nitrobenzenes and terminal alkynes bearing various ... A facile synthesis of 1,4-disubstituted 1,2,3-triazoles was achieved from nitrobenzenes and terminal alkynes under mild conditions. The reactions were successful for nitrobenzenes and terminal alkynes bearing various functionalities, from which the 1,2,3-triazole derivatives were smoothly synthesized through a four-step one-pot sequence. 展开更多
关键词 ONE-POT Four-step 1 4-disubstituted 1 2 3-triazoles NITROBENZENES Terminal alkynes
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A Study on the Inclusion of α-Cyclodextrin with Mono-and 1,4-Disubstituted Benzenes by Neural Networks
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作者 Qing Xiang GUO Shi Dong CHU +2 位作者 Yong Min WANG Zhong Xiao PAN Mao Sen ZHANG and You Cheng LIU(Department of Chemical Physics, University of Science and Technology of China, Hefei 230026) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第2期145-148,共4页
The association constant (Ka) values were calculated by the function-strengthen ing neural networks (FNN) for the inclusion complexation of α-CD with mono- and 1,4-disubstituted benzenes. The lnKa predicted by FNN fr... The association constant (Ka) values were calculated by the function-strengthen ing neural networks (FNN) for the inclusion complexation of α-CD with mono- and 1,4-disubstituted benzenes. The lnKa predicted by FNN from Rm, π and σ constants of substituents are in great agreement with the experimental data. 展开更多
关键词 MONO A Study on the Inclusion of Cyclodextrin with Mono-and 1 4-disubstituted Benzenes by Neural Networks
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Synthesis and Antibacterial Activities of 1,4-Disubstituted Phenyl-5-(halo-2-hydroxyphenyl)imino-1,2,3-triazole
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作者 ZHAO Xu LU Jun-rui +6 位作者 XIN Chun-wei LU Bo-wei BAO Xiu-rong LI Jian-fa LIU Ya YANG Xu-yun YUAN Yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期424-429,共6页
According to the superposition principle of reinforcement of biological activities, 24 novel 1,4- disubstituted phenyl-5-(halo-2-hydroxyphenyl)imino-l,2,3-triazoles was synthesized and characterized by 1H NMR, ^13C ... According to the superposition principle of reinforcement of biological activities, 24 novel 1,4- disubstituted phenyl-5-(halo-2-hydroxyphenyl)imino-l,2,3-triazoles was synthesized and characterized by 1H NMR, ^13C NMR, elemental analysis and IR. All the target compounds were screened for their antibacterial potential in vitro against Monilia albican, Escherichia coli and Staphylococcus aureus. It was shown that all the compounds possessed efficient antibacterial activities at a concentration of 0.1 mg/mL, even at a concentration of 0.01 mg/mL, some of the compounds still exhibited antibacterial activities against Escherichia coli and Monilia albican. At last, the struc- ture-activity relationship was discussed based on the antibacterial results. 展开更多
关键词 1 4-disubstituted phenyl-5-(halo-2-hydroxyphenyl)imino-l 2 3-triazole Antibacterial activity Structure-activity relationship
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Copper iodide nanoparticles on poly(4-vinyl pyridine) as new and green catalyst for multicomponent click synthesis of 1,4-disubstituted-l,2,3-triazoles in water 被引量:4
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作者 Jalal Albadi Mosadegh Keshavarz +1 位作者 Masoumeh Abedini Masoumeh Vafaie-nezhad 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第7期797-800,共4页
Poly(4-vinyl pyridine) supported nanoparticle of copper(Ⅰ) iodide is reported as a green and recyclable catalyst for the regioselective synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from benzyl halides,sodium... Poly(4-vinyl pyridine) supported nanoparticle of copper(Ⅰ) iodide is reported as a green and recyclable catalyst for the regioselective synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from benzyl halides,sodium azide and terminal alkynes in water. This catalyst can be recovered by simple filtration and recycled up to 8 consecutive runs without any loss of its efficiency. 展开更多
关键词 Click chemistry Poly(4-vinyl pyridine) supported NANOPARTICLES Copper(1) iodide TRIAZOLES
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N-Methylpyridinium tosylate catalyzed green and efficient synthesis of some novel 2,4-disubstituted thiazoles and 4-thiazolidinones 被引量:1
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作者 Deepika Gautam Poonam Gautam R.P.Chaudhary 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第11期1221-1224,共4页
A convenient solvent less cyclocondensation from thiosemicarbazone of benzofuranone and chloroacetic acid using an ionic liquid, N-methylpyridinium tosylate for obtaining novel 4-thiazolidinones in excellent yields is... A convenient solvent less cyclocondensation from thiosemicarbazone of benzofuranone and chloroacetic acid using an ionic liquid, N-methylpyridinium tosylate for obtaining novel 4-thiazolidinones in excellent yields is reported. Also, the green expedient synthesis of new 2,4-disubstituted thiazoles under grinding condition from phenacyl bromides and thiosemicarbazide derivatives in quantitative yields is reported. 展开更多
关键词 4-Thiazolidinones THIAZOLES Grinding Ionic liquid CYCLOCONDENSATION THIOSEMICARBAZONES
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Pd-NHC-Catalyzed Direct Arylation of 1,4-Disubstituted 1,2,3-Triazoles with Aryl Halides 被引量:1
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作者 何涛 王敏 +1 位作者 李品华 王磊 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第4期979-984,共6页
A highly efficient method for the synthesis of unsymmetrical multi-substituted 1,2,3-triazoles via a direct Pd-NHC system catalyzed C(5)-arylation of 1,4-disubstituted triazoles, which are readily accessible via "c... A highly efficient method for the synthesis of unsymmetrical multi-substituted 1,2,3-triazoles via a direct Pd-NHC system catalyzed C(5)-arylation of 1,4-disubstituted triazoles, which are readily accessible via "click" chemistry has been developed. It is important to note that C--H bond functionalizations of 1,2,3-triazoles with a variety of differently substituted aryl iodides and bromides as electrophiles can be conveniently achieved through this catalytic system at significantly milder reaction temperatures of 100 ℃ under air. 展开更多
关键词 C--H activation PALLADIUM N-heterocyclic carbene 1 4-disubstituted 1 2 3-triazole C(5)-arylation
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Carboalumination-Epoxide Ring Opening for the Formation of 1,4-Disubstituted (Z)-3,6-Alkadienols
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作者 Quan Zhang Yuhuan Jing +2 位作者 David C. Myles Yong Li Yue Chen 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第6期773-778,共6页
Allylalumination of alkynes (i.e. forming Negishi's (Z)-alkenyl dialkylalane) followed by alkenylation of epoxides provides 1,4-disubstituted (Z)-3,6-alkadienols. The alkenylation can be facilitated by the pres... Allylalumination of alkynes (i.e. forming Negishi's (Z)-alkenyl dialkylalane) followed by alkenylation of epoxides provides 1,4-disubstituted (Z)-3,6-alkadienols. The alkenylation can be facilitated by the presence of a neighbouring coordinating group in the epoxides. This "one-pot" approach has been successfully applied in the large-scale production of C 10--C 15 fragment of 9,10-didehydroepothilone D (a synthetic epothilone analog as an anti-cancer agent in phase 2 clinical trials). 展开更多
关键词 carboalumination-epoxide ring opening 1 4-disubstituted (Z)-3 6-alkadienols
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口腔白斑患者IFITM4P与PD-L1表达特征的临床意义
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作者 姚国华 《河北北方学院学报(自然科学版)》 2026年第2期25-28,共4页
目的分析长链非编码RNA IFITM4P与免疫调节因子PD-L1在口腔白斑病变组织中的表达模式、相互作用及其临床意义。方法回顾性分析68例口腔白斑样本及68例因非肿瘤性疾病手术获取的正常口腔黏膜样本,运用实时荧光定量PCR、免疫组化、蛋白免... 目的分析长链非编码RNA IFITM4P与免疫调节因子PD-L1在口腔白斑病变组织中的表达模式、相互作用及其临床意义。方法回顾性分析68例口腔白斑样本及68例因非肿瘤性疾病手术获取的正常口腔黏膜样本,运用实时荧光定量PCR、免疫组化、蛋白免疫印迹及RNA原位杂交技术检测IFITM4P、PD-L1水平。结果IFITM4P及PD-L1在病变组织中的表达均显著上调(P<0.01),且表达水平呈正相关(r=0.782,P<0.001)。中重度上皮异常增生病例中两者表达进一步增强(P<0.01)。IFITM4P高表达与病变恶性转化风险升高密切相关(P<0.01)。结论IFITM4P可能借由双重分子通路调控PD-L1,参与口腔白斑免疫微环境重塑及恶性演进,可为免疫靶向治疗提供理论参考。 展开更多
关键词 口腔白斑 IFITM4P PD-L1 免疫微环境 生物标志物
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Synthesis, anti-fibrosis activity, and quantitative structure-activity relationship studies of 1,3-disubstituted-pyridin-4(1H)-one derivatives
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作者 彭娟 李乾斌 +2 位作者 向红琳 王泽瑜 胡高云 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2016年第6期395-407,共13页
A series of 1,3-disubstituted-pyridin-4(1H)-one derivatives were synthesized. The results of a viability assay on NIH_T3 cells indicated that compound 3m potently inhibited the cell viability with an IC50 value of 2... A series of 1,3-disubstituted-pyridin-4(1H)-one derivatives were synthesized. The results of a viability assay on NIH_T3 cells indicated that compound 3m potently inhibited the cell viability with an IC50 value of 2.0 μM. The 3D-quantitative structure-activity relationship analyses of 30 final molecules applying topomer CoMFA and AutoGPA methods gave two reasonable models with a cross-validated correlation coefficient q^2 of 0.662 and 0.787, respectively. The achievement herein suggested the application of 3-hydroxypyridin-4(1H)-one as a novel scaffold for the discovery of anti-fibrosis agents. In addition, the QSAR and pharmacophore models established with the activity data may provide new insights into the structure optimization of pyridin-4(1H)-one derivative with potent anti-fibrotic effects. 展开更多
关键词 Pyridin-4(1H)-one QSAR Anti-fibrosis agents
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Synthesis and cytotoxic activity of novel 2,6-disubstituted-4-morpholinothieno[3,2-d]pyrimidines as potent anti-tumor agents 被引量:3
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作者 Wu Fu Zhu Xin Zhai Sai Li Yun Yun Cao Ping Gong Ya Jing Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期703-706,共4页
A series of 2,6-disubstituted-4-morpholinothieno[3,2-d]pyrimidine derivatives were synthesized and their cytotoxic activity against H460, HT-29, MDA-MB-231, U87MG and H1975 cancer cell lines were evaluated in vitro. M... A series of 2,6-disubstituted-4-morpholinothieno[3,2-d]pyrimidine derivatives were synthesized and their cytotoxic activity against H460, HT-29, MDA-MB-231, U87MG and H1975 cancer cell lines were evaluated in vitro. Most of the target compounds exhibited moderate to excellent activity to the tested cell lines. The most promising compound 23 (0.84 μmol/L, 0.23 μmol/L, 2.52 μmogL, 1.80 μmol/L) was 1.0, 2.9, 29.3 and 4.3 times more active than GDC-0941 (0.87 μ mol/L, 0.66μmol/L, 73.8 μmol/L, 7.77 μmol/L) against H460, HT-29, MDA-MB-231 and U87MG cell lines, respectively. 展开更多
关键词 4-Morpholinothieno[3 2-d]pyrimidine SYNTHESIS Cytotoxic activity
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Synthesis and <i>in Vitro</i>Biological Activities of 4,5-Disubstituted 1,2,4-Triazole-3-Thiols 被引量:1
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作者 Humaira Nadeem Muhammad Mohsin +3 位作者 Hasan Afzaal Sadaf Riaz Ammar Zahid Syed Aun Muhammad 《Advances in Microbiology》 2013年第4期366-375,共10页
Purpose: The triazole nucleus is an important part of the therapeutically interesting drug candidate as antimicrobial, analgesic, anticancer, anticonvulsant and anti-inflammatory agents. Methods: Therefore, in this st... Purpose: The triazole nucleus is an important part of the therapeutically interesting drug candidate as antimicrobial, analgesic, anticancer, anticonvulsant and anti-inflammatory agents. Methods: Therefore, in this study, twelve 4,5-disubstituted-1,2,4-triazole-3-thiols were synthesized by the reaction of substituted isothiocyanates and hydrazides using the common method of base catalysed intramolecular dehydrative cyclization of substituted thiosemicarbazides 3(a-f) and 4(a-f). The structures of these compounds were characterized by means of FT-IR, 1H-NMR, and elemental analysis data. All these compounds were screened for antibacterial, antioxidant, antitumor and cytotoxic activities. Results: Among these compounds: 5c, 5f and 6f were found active against gram positive cocci, the compounds 5a, 5b, 5d, 6a and 6f showed 85% free radical scavenging effect at 3 ppm when tested for antioxidant activity, 75% tumors inhibition was recorded using 5c, 5d and 6a and brine shrimps lethality assay declared 5a, 5b and 6d was 129.62 μg/ml, 161.577 μg/ml and 81.56 μg/ml respectively. Conclusion: Compounds carrying significant bioactivity can be further studied using animal models to establish their safety profile prior to initiating clinical trials. 展开更多
关键词 4 5-disubstituted 1 2 4-Triazole-3-Thiols Antibacterial Antitumor Antioxidant Cytotoxic
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Synthesis and cytotoxic activity of 2,5-disubstituted pyrimido[5,4-c]quinoline derivatives 被引量:2
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作者 Fan Zhang Xin Zhai +4 位作者 Li Juan Chen Jian Guo Qi Bo Cui Yu Cheng Gu Ping Gong 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第11期1277-1280,共4页
A series of 2,5-disubstituted pyrimido[5,4-c]quinoline derivatives were synthesized and their cytotoxic activity against H460, HT-29 and MDA-MB-231 cell lines was evaluated in vitro.It was found that most of the teste... A series of 2,5-disubstituted pyrimido[5,4-c]quinoline derivatives were synthesized and their cytotoxic activity against H460, HT-29 and MDA-MB-231 cell lines was evaluated in vitro.It was found that most of the tested compounds especially compound 17, shown stronger activity to the selected three cell lines than ZM447439. 展开更多
关键词 Pyrimido[5 4-c]quinoline SYNTHESIS Cytotoxic activity
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A H_(4)SiW_(12)O_(40)-catalyzed three-component tandem reaction for the synthesis of 3,3-disubstituted isoindolinones 被引量:1
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作者 Yufeng Liu Guodong Zeng +4 位作者 Yutao Cheng Lei Chen Yunhai Liu Yongge Wei Guoping Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期233-236,共4页
A H_(4)SiW_(12)O_(40)-catalyzed three-component tandem reaction of 2-acylbenzoic acids,primary amines and phosphine oxides to form 3,3-disubstituted isoindolinones was developed.By employing A H_(4)SiW_(12)O_(40)as th... A H_(4)SiW_(12)O_(40)-catalyzed three-component tandem reaction of 2-acylbenzoic acids,primary amines and phosphine oxides to form 3,3-disubstituted isoindolinones was developed.By employing A H_(4)SiW_(12)O_(40)as the catalyst and dimethyl carbonate(DMC)as the solvent,a diverse range of 2-acylbenzoic acid derivatives and primary amines worked well to give the C3-phosphinoyl-functionalized 3,3-disubstituted isoindolinones with the yield range of 61%-87%.Advantages of this transformation include green catalyst and solvent,available starting materials,broad substrate scope,high efficiency and operational simplicity with water as the sole by-product.The strategy achieved an efficient and green molecular fragment assembly to access isoindolinones,which would provide opportunities for the synthesis of potential biologically active molecules in a green manner. 展开更多
关键词 POLYOXOMETALATES Dehydrative coupling Three-component tandem reaction 3 3-disubstituted isoindolinones Organic carbonate
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羟基磷灰石/氧化石墨烯/白细胞介素4涂层材料的理化性质及生物相容性
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作者 李丛丛 吾凡别克·巴合提 +3 位作者 赵莉 陈晓涛 孔垂范 俞敏 《中国组织工程研究》 北大核心 2026年第2期404-413,共10页
背景:纯钛及钛合金种植体因良好的生物相容性及弹性模量被广泛应用于种植修复领域,但钛基种植体表面的生物惰性导致其与周围骨组织的整合性较差,需要进行表面修饰提高钛基种植体的骨整合能力。目的:在纯钛片表面制备羟基磷灰石/氧化石墨... 背景:纯钛及钛合金种植体因良好的生物相容性及弹性模量被广泛应用于种植修复领域,但钛基种植体表面的生物惰性导致其与周围骨组织的整合性较差,需要进行表面修饰提高钛基种植体的骨整合能力。目的:在纯钛片表面制备羟基磷灰石/氧化石墨烯/白细胞介素4涂层材料,探究涂层材料的理化性能与生物相容性。方法:通过电化学沉积法及浸泡冻干法在钛片表面制备负载羟基磷灰石/氧化石墨烯/白细胞介素4涂层,同时制备负载白细胞介素4的钛片与负载羟基磷灰石/氧化石墨烯涂层的钛片,表征纯钛片及上述3种钛片的理化性能。将MC3T3-E1细胞分别接种于纯钛片及上述3种钛片的表面,通过CCK-8、DAPI染色检测细胞增殖,Calcein-AM/PI染色检测细胞活性,扫描电镜观察细胞形态与黏附。结果与结论:①扫描电镜、X射线能量色散谱、X射线光电子能谱、X射线衍射谱、拉曼光谱检测显示,在钛片表面成功制备了羟基磷灰石/氧化石墨烯/白细胞介素4涂层。羟基磷灰石/氧化石墨烯/白细胞介素4组水接触角大于纯钛组、羟基磷灰石/氧化石墨烯组,小于白细胞介素4组。②CCK-8、DAPI染色结果显示,羟基磷灰石/氧化石墨烯/白细胞介素4涂层可促进MC3T3-E1细胞增殖。Calcein-AM/PI染色结果显示,羟基磷灰石/氧化石墨烯/白细胞介素4涂层组MC3T3-E1细胞活性较高,较少见死细胞。扫描电镜下可见MC3T3-E1细胞黏附于4组材料表面,细胞形态良好,相较于纯钛组,白细胞介素4组MC3T3-E1细胞伸出伪足更多,细胞间联系更加紧密,黏附面积更大;相较于羟基磷灰石/氧化石墨烯组,羟基磷灰石/氧化石墨烯/白细胞介素4组MC3T3-E1细胞伸出伪足更多,细胞间联系更加紧密,黏附面积更大。③结果表明,羟基磷灰石/氧化石墨烯/白细胞介素4涂层具有良好的理化性能及生物学性能。 展开更多
关键词 氧化石墨烯 羟基磷灰石 白细胞介素4 种植体复合涂层 MC3T3-E1细胞 生物相容性 工程化材料
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SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF 3,6-DISUBSTITUTED S-TRIAZOLO[3,4-b]-1,3,4-THIADIAZOLES 被引量:1
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作者 Zi Yi ZHANG Xin CHEN Department of Chemistry,Lanzhou University,Lanzhou 730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期277-278,共2页
A series of 3,6-disubstituted s-triazolo[3,4-b]-1,3,4-thiadiazoles have been synthesized,whose structures were determined by elemental and spectral analyses;all the new compounds showed significant antibacterial activ... A series of 3,6-disubstituted s-triazolo[3,4-b]-1,3,4-thiadiazoles have been synthesized,whose structures were determined by elemental and spectral analyses;all the new compounds showed significant antibacterial activity. 展开更多
关键词 DMF 甲酰胺 SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF 3 6-disubstituted S-TRIAZOLO[3 4-b THIADIAZOLES
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Catalytic activity of TiO_2 nanoparticles in the synthesis of some2,3-disubstituted dihydroquinazolin-4(1H)-ones 被引量:1
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作者 A.Bharathi Selvaraj Mohana Roopan +3 位作者 Amir Kajbafvala R.D.Padmaja M.S.Darsana G.Nandhini Kumari 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第2期324-326,共3页
Green chemistry is playing an important role for synthesizing organic compounds, due to its eco-friendly nature and low cost. In green chemistry, metal nanoparticles exhibited some useful physical and chemical propert... Green chemistry is playing an important role for synthesizing organic compounds, due to its eco-friendly nature and low cost. In green chemistry, metal nanoparticles exhibited some useful physical and chemical properties (catalytic activity). Due to its diverse properties, nanoparticles can be utilized as a catalyst in various organic reactions. Recent research has been directed towards the utilization of eco- friendly and bio-friendly plant materials in nanoparticles synthesis. In our present work, TiO2 nanoparticles (TiO2 NPs) were synthesized using Annona squamosa peel extract and their catalytic applications were studied on the 2,3-disubstituted dihydroquinazolin-4(l1H)-one synthesis. Synthesized compounds were confirmed using FT-IR.1H NMR, 13C NMR and GC-MS analyses. 展开更多
关键词 TiO2 nanoparticles Quinazolin-4(1H)-one Green chemistry
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SYNTHESIS OF 4,6-DISUBSTITUTED 5-THIOXO-1,2,4-TRIAZIN-3-ONE FROM BENZOTHIOFORMANILIDE
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作者 Zhong E LU Tian Lin XU Xiao Dong SHI Department of Chemistry,Suzhou University,Suzhou,215006 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期525-526,共2页
A method of synthesis of 4,6-disubstituted 5-thioxo-1,2,4-triazin- 3-ones from benzothioformanilides and semicarbazide is described.And six new compounds were synthesized by this method.
关键词 SYNTHESIS OF 4 6-disubstituted 5-THIOXO-1 2 4-TRIAZIN-3-ONE FROM BENZOTHIOFORMANILIDE
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Bornylimidazo[1,5-a]pyridin-3-ylidene allylic Pd catalyst with optimal electronic and steric properties for synthesis of 3,3'-disubstituted oxindoles
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作者 Kun Wang Tianxue Gong +4 位作者 Yaohuang Huang Boyang Han Hanxiao Yang Pavlo O.Dral Weiwei Fang 《Chinese Chemical Letters》 2025年第7期348-353,共6页
A robust bulky bornylimidazo[1,5-a]pyridin-3-ylidene allylic Pd complex was synthesized and well characterized.DFT calculations indicated that the ligand acts as a strongσ-donor andπ-acceptor endowing the active Pd(... A robust bulky bornylimidazo[1,5-a]pyridin-3-ylidene allylic Pd complex was synthesized and well characterized.DFT calculations indicated that the ligand acts as a strongσ-donor andπ-acceptor endowing the active Pd(0)center with high electron density and good coordination towards olefin.The introduction of a bulky,rigid bornyl ring further improved the catalytic efficacy due to the matched steric effects.This catalyst showed high efficiency and versatility in theα-arylation and Heck cyclization/Suzuki crosscoupling reactions at mild reaction conditions.Desired 3,3-disubstituted oxindoles,especially featuring an allylic-derived C3-quaternary stereocenter were obtained in high yields.Furthermore,the concise synthesis of bioactive heterocycle-fused indoline alkaloids was successfully proved. 展开更多
关键词 Pd catalyst Cross-coupling reaction DFT calculations 3 3-disubstituted oxindoles Imidazo[1 5-a]pyridin-3-ylidene
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