期刊文献+
共找到382篇文章
< 1 2 20 >
每页显示 20 50 100
C-H bond activation of propane on Ga_(2)O_(2)^(2+) in Ga/H-ZSM-5 and its mechanistic implications
1
作者 Zhaoqi Zhao Yunzhu Zhong +1 位作者 Xiaoxia Chang Bingjun Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期32-43,共12页
Propane dehydrogenation(PDH)on Ga/H-ZSM-5 catalysts is a promising reaction for propylene production,while the detail mechanism remains debatable.Ga_(2)O_(2)^(2+) stabilized by framework Al pairs have been identified ... Propane dehydrogenation(PDH)on Ga/H-ZSM-5 catalysts is a promising reaction for propylene production,while the detail mechanism remains debatable.Ga_(2)O_(2)^(2+) stabilized by framework Al pairs have been identified as the most active species in Ga/H-ZSM-5 for PDH in our recent work.Here we demonstrate a strong correlation between the PDH activity and a fraction of Ga_(2)O_(2)^(2+) species corresponding to the infrared GaH band of higher wavenumber(GaHHW)in reduced Ga/H-ZSM-5,instead of the overall Ga_(2)O_(2)^(2+) species,by employing five H-ZSM-5 supports sourced differently with comparable Si/Al ratio.This disparity in Ga_(2)O_(2)^(2+) species stems from their differing capacity in completing the catalytic cycle.Spectroscopic results suggest that PDH proceeds via a two-step mechanism:(1)C-H bond activation of propane on H-Ga_(2)O_(2)^(2+) species(rate determining step);(2)β-hydride elimination of adsorbed propyl group,which only occurs on active Ga_(2)O_(2)^(2+) species corresponding to GaHHW. 展开更多
关键词 Propane dehydrogenation Ga_(2)O_(2)^(2+) activation of c-h bond Ga species
下载PDF
Oxidative co-dehydrogenation of ethane and propane over h-BN as an effective means for C-H bond activation and mechanistic investigations 被引量:4
2
作者 Hao Tian Bingjun Xu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2173-2182,共10页
Hexagonal boron nitride(h-BN)is a highly selective catalyst for oxidative dehydrogenation of light alkanes to produce the corresponding alkenes.Despite intense recent research effort,many aspects of the reaction mecha... Hexagonal boron nitride(h-BN)is a highly selective catalyst for oxidative dehydrogenation of light alkanes to produce the corresponding alkenes.Despite intense recent research effort,many aspects of the reaction mechanism,such as the observed supra-linear reaction order of alkanes,remain unresolved.In this work,we show that the introduction of a low concentration of propane in the feed of ethane oxidative dehydrogenation is able to enhance the C_(2)H_(6) conversion by 47%,indicating a shared reaction intermediate in the activation of ethane and propane.The higher activity of propane makes it the dominant radical generator in the oxidative co-dehydrogenation of ethane and propane(ODEP).This unique feature of the ODEP renders propane an effective probe molecule to deconvolute the two roles of alkanes in the dehydrogenation chemistry,i.e.,radical generator and substrate.Kinetic studies indicate that both the radical generation and the dehydrogenation pathways exhibit a first order kinetics toward the alkane partial pressure,leading to the observed second order kinetics of the overall oxidative dehydrogenation rate.With the steady-state approximation,a radical chain reaction mechanism capable of rationalizing observed reaction behaviors is proposed based on these insights.This work demonstrates the potential of ODEP as a strategy of both activating light alkanes in oxidative dehydrogenation on BN and mechanistic investigations. 展开更多
关键词 Hexagonal boron nitride Oxidative dehydrogenation Radical chain reaction Reaction order c-h activation
下载PDF
Site-specific deposition creates electron-rich Pd atoms for unprecedented C-H activation in aerobic alcohol oxidation 被引量:2
3
作者 Yang Yan Bin Ye +8 位作者 Mingshu Chen Linfang Lu Jian Yu Yuheng Zhou Yong Wang Juanjuan Liu Liping Xiao Shihui Zou Jie Fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第8期1240-1247,共8页
Here,we demonstrate a photochemical strategy to site-specifically deposit Pd atoms on Au nanoparticles.The high-sensitivity low-energy ion scattering spectra combined with the X-ray photoelectron spectra reveal that t... Here,we demonstrate a photochemical strategy to site-specifically deposit Pd atoms on Au nanoparticles.The high-sensitivity low-energy ion scattering spectra combined with the X-ray photoelectron spectra reveal that the surface electronic structure of Pd can be continuously regulated by tailoring the Pd-to-Au molar ratio and the location of Pd atoms in Au Pd nanoparticles.It is revealed that electron-rich Pd atoms are considerably more active than the net Pd atoms in aerobic alcohol oxidation.Remarkably,the catalyst with the most electron-rich Pd sites(binding energy downshift:1.0 e V)exhibits an extremely high turnover frequency(~500000 h-1 vs 12000 h-1 for that with net Pd atoms)for solvent-free selective oxidation of benzyl alcohol,which is,to the best of our knowledge,the highest value ever reported.Kinetic studies reveal that electron-rich Pd atoms can accelerate the oxidation of benzyl alcohol by facilitating C-H cleavage,as indicated by the significant reduction in the activation energy as compared to net Pd atoms. 展开更多
关键词 AuPd/TiO2 Benzyl alcohol Selective oxidation c-h activation Electronic structure
下载PDF
A Mechanistic Switch in C-H Bond Activation by Elusive Fe^(V)(O)(TAML)Reaction Intermediate:A Theoretical Study 被引量:1
4
作者 Anran Zhou Zhiqiang Fu +2 位作者 Xuanyu Cao Yufen Zhao Yong Wang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第2期383-389,I0032-I0064,I0004,共41页
The divergent behavior of C-H bond oxidations of aliphatic substrates compared to those of aromatic substrates shown in Gupta’s experiment was mechanistically studied herein by means of density functional theory calc... The divergent behavior of C-H bond oxidations of aliphatic substrates compared to those of aromatic substrates shown in Gupta’s experiment was mechanistically studied herein by means of density functional theory calculations.Our calculations reveal that such difference is caused by different reaction mechanisms between two kinds of substrates(the aliphatic cyclohexane,2,3-dimethylbutane and the aromatic toluene,ethylbenzene and cumene).For the aliphatic substrates,C-H oxidation by the oxidant Fe^(V)(O)(TAML)is a hydrogen atom transfer process;whereas for the aromatic substrates,C-H oxidation is a proton-coupled electron transfer(PCET)process with a proton transfer character on the transition state,that is,a proton-coupled electron transfer process holding a proton transfer-like transition state(PCET(PT)).This difference is caused by the strongπ-πinteractions between the tetra-anionic TAML ring and the phenyl ring of the aromatic substrates,which has a“pull”effect to make the electron transfer from substrates to the Fe=O moiety inefficient. 展开更多
关键词 c-h bond activation Hydrogen atom transfer Proton coupled electron transfer Density functional theory
下载PDF
Synthesizing active and durable cubic ceria catalysts(<6 nm)for fast dehydrogenation of bio-polyols to carboxylic acids coproducing green H_(2)
5
作者 Mengyuan Liu Puhua Sun +3 位作者 Guangyu Zhang Xin Jin Chaohe Yang Honghong Shan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期529-543,共15页
Dehydrogenation is considered as one of the most important industrial applications for renewable energy.Cubic ceria-based catalysts are known to display promising dehydrogenation performances in this area.Large partic... Dehydrogenation is considered as one of the most important industrial applications for renewable energy.Cubic ceria-based catalysts are known to display promising dehydrogenation performances in this area.Large particle size(>20 nm)and less surface defects,however,hinder further application of ceria materials.Herein,an alternative strategy involving lactic acid(LA)assisted hydrothermal method was developed to synthesize active,selective and durable cubic ceria of<6 nm for dehydrogenation reactions.Detailed studies of growth mechanism revealed that,the carboxyl and hydroxyl groups in LA molecule synergistically manipulate the morphological evolution of ceria precursors.Carboxyl groups determine the cubic shape and particle size,while hydroxyl groups promote compositional transformation of ceria precursors into CeO_(2) phases.Moreover,enhanced oxygen vacancies(Vo)on the surface of CeO_(2) were obtained owing to continuous removal of O species under reductive atmosphere.Cubic CeO_(2) catalysts synthesized by the LA-assisted method,immobilized with bimetallic PtCo clusters,exhibit a record high activity(TOF:29,241 h^(-1))and Vo-dependent synergism for dehydrogenation of bio-derived polyols at 200℃.We also found that quenching Vo defects at air atmosphere causes activity loss of PtCo/CeO_(2) catalysts.To regenerate Vo defects,a simple strategy was developed by irradiating deactivated catalysts using hernia lamp.The outcome of this work will provide new insights into manufacturing durable catalyst materials for aqueous phase dehydrogenation applications. 展开更多
关键词 Cubic ceria Oxygen vacancy DEHYDROGENATION c-h bond activation
下载PDF
Photocatalytic C-H Bonds Activation:Ambient Carbonylation of Cyclohexane by Co(acac)_2 Under Ultraviolet Irradiation
6
作者 Da Bin GAo Jing Mei YIN +1 位作者 Ming GUO Yuan YU(Departemnt of Chemistry & Chemical Engineering, Dalian University, Dalian 116622)Yong An MA(National Marine Environmental Monitoring Center, Institute of Marine Environmental Protection, State Oceanic Administrat 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第9期763-764,共2页
A high turnover number was achieved in the photocatalytic carbonylation of C - H bonds of cyclohexane catalyzed by Co (acac)2 under ambient conditions (1 atm,25℃) to give mainly cyclohexanecarboxaldehyde.
关键词 acac Photocatalytic c-h Bonds activation Under Ultraviolet Irradiation
下载PDF
Competition between C-C and C-H Activation in Reactions of Neutral Nickel Atom with Cycloalkanes (n = 3-7)
7
作者 杨静 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第1期122-134,共13页
A theoretical investigation of the reaction mechanisms for C-H and C-C bond activation processes in the reaction of Ni with cycloalkanes C,,H2. (n = 3-7) is carried out. For the Ni + CnH2, (n = 3, 4) reactions, t... A theoretical investigation of the reaction mechanisms for C-H and C-C bond activation processes in the reaction of Ni with cycloalkanes C,,H2. (n = 3-7) is carried out. For the Ni + CnH2, (n = 3, 4) reactions, the major and minor reaction channels involve C-C and C-H bond activations, respectively, whereas Ni atom prefers the attacking of C-H bond over the C-C bond in CnH2n (n = 5=7). The results are in good agreement with the experimental study. In all cases, intermediates and transition states along the reaction paths of interest are characterized, It is found that both the C-H and C-C bond activation processes are proposed to proceed in a one-step manner via one transition state. The overall C-H and C-C bond activation processes are exothermic and involve low energy barriers, thus transition metal atom Ni is a good mediator for the activity of cycloalkanes CnH2n (n = 3 -7). 展开更多
关键词 reaction mechanism c-h bond activation C-C bond activation cycioalkanes nickel atom
下载PDF
Synthesis and Anti-inflammatory Activity of 2-(E)-(4-Hy-droxy-3-methoxybenzylidene)-5-(N-Substituted aminomethyl)Cyclopentanones 被引量:1
8
作者 董金华 徐莉英 +3 位作者 秦华 许丁元 李莉 计志忠 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第4期19-23,共5页
A series of 2 (E) (4 hydroxy 3 methoxybenzylidene) 5 (N substituted ami nomethyl) cyclopentanones was synthesized and evaluated for the anti inflammatory activity. All of the target compounds were confirmed ... A series of 2 (E) (4 hydroxy 3 methoxybenzylidene) 5 (N substituted ami nomethyl) cyclopentanones was synthesized and evaluated for the anti inflammatory activity. All of the target compounds were confirmed by spectral analysis and elemental analysis. Preliminary pharmacological tests showed that several compounds exerted appreciable inhibitory effect on xylene induced ear edema in mice and that alteration of the substituents of anilines had significant influence in anti inflammatory potency. 展开更多
关键词 Cyclopentanone derivative Mannich base amine exchange reaction Anti inflammatory activity
全文增补中
Catalytic C-H activation-initiated transdiannulation:An oxygen transfer route to ring-fluorinated tricyclic γ-lactones
9
作者 Qiuyun Li Yannan Zhu +4 位作者 Yining Wang Gang Qi Wen-Juan Hao Kelu Yan Bo Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第9期145-149,共5页
Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic chemistry.Herein,... Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic chemistry.Herein,we describe a new Rh(Ⅲ)-catalyzed C–H activation-initiated transdiannulation reaction of N,Ndimethyl enaminones with gem-difluorocyclopropenes in the presence of H_(2)O,enabling a facile and oxygen transfer access to ring-fluorinated tricyclicγ-lactones with a 6-5 ring-junction tetrasubstituted stereocenter.This approach features bond-forming/annulation efficiency,good functional group tolerance and complete regioselectivity,which may include a complex process consisting of Rh(Ⅲ)-catalyzed C(sp2)–H activation,cyclic alkene insertion,defluorinated ring-opening of gem-difluorocyclopropane,intramolecular oxygen transfer,intramolecular cyclization and oxidative hydration. 展开更多
关键词 c-h bond activation ENaminONES Transannulation Oxygen transfer Regioselectivity
原文传递
Partial amination of cationic exchange resins and its application in the hydration of butene 被引量:3
10
作者 Deren Fang Wanzhong Ren +1 位作者 Hongying Lu Hongtao Yang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第3期314-318,共5页
In this work, the amination of sulfonated polystyrene resin with alkyl secondary amine is investigated. The catalytic activities of the modified resins are determined through the hydration of l-butene. The optimum cha... In this work, the amination of sulfonated polystyrene resin with alkyl secondary amine is investigated. The catalytic activities of the modified resins are determined through the hydration of l-butene. The optimum chain length and the best range of amination rate are determined. It is found that the single-pass conversion of 1 -butene was raised 2% on average, and the relative activity was increased over 30% after modification. A hypothesis about the enhancement of catalytic activities by the inclusion of alkyl chain to wrap up the butene molecule is proposed. 展开更多
关键词 amination sulfonated polystyrene resin butene hydration catalytic activity mechanism inclusion
下载PDF
Adsorption of residual amine collector HAY from aqueous solution by refined carbon from coal fly ash and activated carbon 被引量:2
11
作者 李显波 叶军建 +4 位作者 邱跃琴 李龙江 卯松 刘志红 张覃 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期30-38,共9页
Refined carbon(RC) derived from coal fly ash(CFA) as well as powdered activated carbon(PAC) was investigated as adsorbent to remove residual amine collector HAY from aqueous solution.The RC and PAC were characterized ... Refined carbon(RC) derived from coal fly ash(CFA) as well as powdered activated carbon(PAC) was investigated as adsorbent to remove residual amine collector HAY from aqueous solution.The RC and PAC were characterized by scanning electron microscopy(SEM),surface area measurement,Zeta potential measurement and Fourier transform infrared(FTIR) spectroscopy.The effect factors and mechanisms of HAY adsorption onto RC and PAC were studied in detail.The results show that the experimental kinetic data agree well with the pseudo second-order equation,and the Langmuir isotherm model is found to be more appropriate to explicate the experimental equilibrium isotherm results than the Freundlich model.The adsorption capacities of PAC and RC increase with pH.It is found that alkaline condition is conducive to the adsorption of HAY onto PAC and RC and the adsorption efficiency of RC is close to PAC at pH near 11.Zeta potential variation of adsorbents suggests that HAY generates electrostatic adsorption onto RC and PAC.FTIR analysis shows that the adsorption is dominantly of a physical process.The Box-Behnken design optimization conditions of process are RC 1 g/L,pH 11,temperature 302 K and initial HAY concentration 100 mg/L.Under these conditions,the measured adsorption ratio and adsorption capacity are 87.91%and 87.91 mg/g,respectively.Thus,the RC is considered to be a potential adsorbent for the removal of residual amine from aqueous solution. 展开更多
关键词 powdered activated carbon coal fly ash refined carbon ADSORPTION amine collector HAY
下载PDF
Synthesis and fungicidal activity of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines 被引量:4
12
作者 Hui Chao Li Bao Shan Chai +2 位作者 Zhi Nian Li Ji Chun Yang Chang Ling Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1287-1290,共4页
A number of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines were synthesized. The structures of these new compounds were confirmed by ^1H NMR, IR and elemental analysis. Biological evalua... A number of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines were synthesized. The structures of these new compounds were confirmed by ^1H NMR, IR and elemental analysis. Biological evaluation in the greenhouse showed several compounds have good fungicidal activities at 25 mg/L. 展开更多
关键词 N-Phenylpyrimidin-2-amine STROBILURIN SYNTHESIS Fungicidal activity
下载PDF
Michael Addition of Amines to Activated Alkenes Promoted by Zn/NH_4Cl System
13
作者 KOU Jing-ping LU Yu-juan +1 位作者 LUO Xu-yang LI Ji-zhen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第4期461-464,共4页
A Zn/NH4Cl system was exploited at room temperature to promote the Michael addition reaction of various primary and secondary amines with α,β-unsaturated esters,nitriles,amides,and ketones to give the corresponding ... A Zn/NH4Cl system was exploited at room temperature to promote the Michael addition reaction of various primary and secondary amines with α,β-unsaturated esters,nitriles,amides,and ketones to give the corresponding saturated amines under the mild condition in high yield. 展开更多
关键词 Michael addition aminES activated alkenes Zn/NH4Cl system
下载PDF
Synthesis, Crystal Structure and Antitumor Activity of (E)-4-tert-Butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine 被引量:5
14
作者 胡艾希 覃智 +1 位作者 叶姣 夏曙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1680-1683,共4页
The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobe... The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobenzaldehyde, and its crystal structure was determined by singlecrystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.9748(4), b = 10.1803(5), c = 11.4603(6), α = 102.882(1), β = 100.253(1), γ = 104.457(1)°, V = 850.95(7)3, Z = 2, F(000) = 392, C16H15Cl2N5S, Mr = 380.29, Dc = 1.484 g/cm3, S = 1.095, μ = 0.512 mm-1, the final R = 0.0301 and wR = 0.0965 for 3334 observed reflections (I 〉 2σ(I)). The preliminary antitumor activity shows that for the title compound the IC50 of Hela is 0.175 μmol/mL and that of Bel7402 is 0.156 μmol/mL. 展开更多
关键词 (E)-4-tert-butyl-N-(2 4-dichorobenzylidene)-5-(1 2 4-triazl-1-yl)-thiazol-2-amine crystal structure synthesis antitumor activity
下载PDF
First Application of Optically Active trans-1,2-Bis(2- aminophenyl)cyclopentane for Asymmetric Reaction: Enantioselective N-Acetylation of Secondary Alkyl Amines
15
《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第1期1-4,共4页
关键词 First Application of Optically active trans-1 2-Bis ENANTIOSELECTIVE N-Acetylation of Secondary Alkyl amines
下载PDF
Synthesis, Crystal Structure and Antitumor Activity of 4-tert-Butyl-N-(2-fluorophenyl)-5- (1H-1,2,4-triazol-1-yl)-thiazol-2-amine 被引量:1
16
作者 李婉 叶姣 +2 位作者 沈芳 彭俊梅 胡艾希 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第12期1782-1786,共5页
The title compound has been synthesized by the reaction of 1-bromo-3,3-dime- thyl- 1 - (1 H- 1,2,4-triazol- 1 -yl)butan-2-one with 1 -(2-fluorophenyl)thiourea, and its crystal struc- ture was determined by single-... The title compound has been synthesized by the reaction of 1-bromo-3,3-dime- thyl- 1 - (1 H- 1,2,4-triazol- 1 -yl)butan-2-one with 1 -(2-fluorophenyl)thiourea, and its crystal struc- ture was determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pbca with a = 15.2568(6), b = 12.1533(5), c = 16.7307(7) A, Z = 8, V = 3102.2(2) A3, Mr = 317.39, Dc = 1.359 g/cm3, S = 1.05, μ = 0.223 mm-1, F(000) = 1328, the final R = 0.034 and wR = 0.097 for 2590 observed reflections (I 〉 2σ(I)). X-ray crystal structure presents the intramolecular N-H…N hydrogen bond, which plays an important role in stabilizing the crystal structure. In addition, the preliminary biological test on the title compound shows good antitumor activity, with IC50 of 0.122 μmol/mL against the Hela cell line. 展开更多
关键词 4-tert-butyl-N-(2-fluorophenyl)-5-(1H-1 2 4-triazol-1-yl)thiazol-2-amine SYNTHESIS crystal structure antitumor activity
下载PDF
Synthesis, Crystal Structure and Antitumor Activity of 4-(tert-butyl)-5-(1H-1,2,4-triazol-1-yl)-N-(2-hydroxy-3,5-diiodinebenzyl)-thiazol-2-amine 被引量:1
17
作者 叶姣 谢选青 +3 位作者 李康明 刘永超 孙利 胡艾希 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期344-348,共5页
The title compound, 4-(tert-butyl)-5-(1 H- 1,2,4-triazol- 1 -yl)-N-(2-hydroxy-3,5-diio- dinebenzyl)thiazol-2-amine, was synthesized via the reduction of 4-(tert-butyl)-5-(1H-l,2,4- triazol-l-yl)-N-benzyliden... The title compound, 4-(tert-butyl)-5-(1 H- 1,2,4-triazol- 1 -yl)-N-(2-hydroxy-3,5-diio- dinebenzyl)thiazol-2-amine, was synthesized via the reduction of 4-(tert-butyl)-5-(1H-l,2,4- triazol-l-yl)-N-benzylidene-thiazol-2-amine with NaBH4, and its crystal structure was determined by single-crystal X-ray diffraction. The compound crystallizes in monoclinic system, space group P21/c with a = 7.91944(19), b = 10.5250(3), c = 24.4985(6) A, Z = 4, V = 2041.66(9) A3, Mr = 599.22, Dc = 1,949 Mg/m3, S = 1.120, p = 3.203 mm-1, F(000) = 1152, the final R = 0.0283 and wR = 0.0592 for 3490 observed reflections (I 〉 2σ(I)). X-ray analysis displays that the crystal water takes part in three intermolecular hydrogen bonds of O(2)-H(2A)…O(1), O(2)-H(2B)…N(I) and N(5)-H(5)…O(2), and an octatomic ring R^(8) is formed via intramolecular hydrogen bond of O(I)-H(IA)…N(4). Furthermore, the I…I contacts are involved in stabilizing the overall three-dimensional network structure. The preliminary biological test shows the title compound has good antitumor activity with the IC50 value of 26 μM against the Hela cell line. 展开更多
关键词 4-(tert-butyl)-5-(1H-1 2 4-triazol-1-yl)-N-(2-hydroxy-3-5-diiodinebenzyl)-thiazol-2-amine synthesis crystal structure antitumor activity
下载PDF
Synthesis, Crystal Structure and Antitumor Activities of N,N,1-Triphenyl-1H-benzo[d]imidazol-5-amine Derivatives
18
作者 SHAO Jia-Xin GUO Zi-Yin +2 位作者 PENG Shi-Yong ZHU Zhong-Zhi CHEN Xiu-Wen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第11期1895-1901,共7页
In order to discover the novel antitumor agents,a series of N,N,1-triphenyl-1Hbenzo[d]imidazol-5-amine derivatives were designed and synthesized,and the structures were characterized by IR,H-RMS,1H and 13C NMR.X-ray c... In order to discover the novel antitumor agents,a series of N,N,1-triphenyl-1Hbenzo[d]imidazol-5-amine derivatives were designed and synthesized,and the structures were characterized by IR,H-RMS,1H and 13C NMR.X-ray crystallography showed that 4c is in monoclinic system,space group P1 with a=9.209(2),b=9.533(3),c=14.097(3)?,β=102.069(3)°,V=1202.2(5)?3,Z=2,F(000)=528,μ=1.74 mm–1,S=1.024,the final R=0.0448 and wR=0.1109.The in vitro antitumor activities of target compounds were evaluated by MTT assay against human cancer cell lines K562,HL-60,HeLa and BGC-823.The target compounds demonstrated weak or moderate antitumor activities against these cell lines. 展开更多
关键词 N N 1-triphenyl-1H-benzo[d]imidazol-5-amine derivatives synthesis crystal structure antitumor activity
下载PDF
Synthesis,Crystal Structure and Antitumor Activity of(E)-N-(4-Fluorobenzylidene)-3-(methylthio)-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazol-4-amine
19
作者 LIN Wei-Yuan YANG Fang +2 位作者 DUAN An-Na YOU Wen-Wei ZHAO Pei-Liang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第10期1557-1562,共6页
The crystal structure of the title compound(E)-N-(4-fluorobenzylidene)-3-(methylthio)-5-(3,4,5-trimethoxyphenyl)-4 H-1,2,4-triazol-4-amine(C_(19)H_(19)FN_4O_3S,Mr = 402.44) was synthesized,and its struct... The crystal structure of the title compound(E)-N-(4-fluorobenzylidene)-3-(methylthio)-5-(3,4,5-trimethoxyphenyl)-4 H-1,2,4-triazol-4-amine(C_(19)H_(19)FN_4O_3S,Mr = 402.44) was synthesized,and its structure was characterized by 1 H-NMR,13 C-NMR,ESI-MS and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P1 with a = 9.228(13),b = 10.364(14),c = 10.641(14) ?,α = 85.323(3),β = 75.172(2),γ = 80.903(3)°,μ = 0.20 mm^(-1),M_r = 402.44,V = 970.64(10) ?~3,Z = 2,D_c = 1.377 g/cm^3,F(000) = 420,R = 0.0484 and wR = 0.1474 for 3181 observed reflections with I 〉 2σ(I).In addition,the preliminary bioassay indicated that the title compound 5 exhibits better inhibitory activity against Hela than 5-fluorouracil. 展开更多
关键词 (E)-N-(4-fluorobenzylidene)-3-(methylthio)-5-(3 4 5-trimethoxyphenyl)-4H-1 2 4-triazol-4-amine SYNTHESIS crystal structure anfitumor activity
下载PDF
晋西北酸粥源短乳杆菌(Levilactobacillus brevis)M-10安全性评估
20
作者 王琪 杨淑艺 +2 位作者 刘鹏帆 蔡瑾 秦文君 《中国调味品》 CAS 北大核心 2024年第7期32-37,共6页
从晋西北酸粥发酵液中分离到一株短乳杆菌M-10,发现其具有耐酸、耐胆盐、抗氧化、抗菌、降胆固醇等多种益生特性。为了更好地应用该菌株,该研究评价了其体外和体内的安全性,包括溶血活性检测、明胶液化能力测定、硝基还原酶活性测定、... 从晋西北酸粥发酵液中分离到一株短乳杆菌M-10,发现其具有耐酸、耐胆盐、抗氧化、抗菌、降胆固醇等多种益生特性。为了更好地应用该菌株,该研究评价了其体外和体内的安全性,包括溶血活性检测、明胶液化能力测定、硝基还原酶活性测定、吲哚和生物胺生成能力测定、SD大鼠急性毒性和亚急性毒性实验。经检测发现,短乳杆菌M-10缺乏溶血活性,不能液化明胶,缺乏硝基还原酶活性,不会生成吲哚,不能产生生物胺,包括酪胺、组胺、尸胺、腐胺等;该菌对SD大鼠的一般体征和血常规指标均无明显不良影响。以上研究结果表明,短乳杆菌M-10具有很好的安全性。该研究可为后续短乳杆菌M-10作为发酵剂或益生菌的开发奠定基础。 展开更多
关键词 晋西北酸粥 短乳杆菌 溶血活性 明胶液化活性 硝基还原酶活性 吲哚测定 生物胺测定 急毒亚急毒实验
下载PDF
上一页 1 2 20 下一页 到第
使用帮助 返回顶部