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Sulfone通过转录因子Elk1调节人结肠癌细胞XAF1表达的研究
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作者 李薇薇 徐琛莹 +1 位作者 蔡劬 俞丽芬 《胃肠病学》 2013年第6期336-340,共5页
背景:Sulfone是一个高效的结肠肿瘤化学预防制剂,具有抗肿瘤功能,但其具体作用机制尚未完全明确。目的:探讨Sulfone在转录水平调节X连锁凋亡抑制蛋白(XIAP)相关因子1(XAF1)表达的作用机制。方法:以Sulfone干预人结肠癌细胞株HCT116,以... 背景:Sulfone是一个高效的结肠肿瘤化学预防制剂,具有抗肿瘤功能,但其具体作用机制尚未完全明确。目的:探讨Sulfone在转录水平调节X连锁凋亡抑制蛋白(XIAP)相关因子1(XAF1)表达的作用机制。方法:以Sulfone干预人结肠癌细胞株HCT116,以蛋白质印迹法检测磷酸化ERK1/2(pERK1/2)、XAF1和ERK1/2表达;构建稳定转染pLuc-291质粒以及pLuc-291-18T、pLuc-291-70T、pLuc-291-IRFm质粒的HCT116细胞(分别为转录因子Elk1、c-ETS、IRF结合序列点突变),以荧光素酶报告基因检测Sulfone对XAF1启动子转录活性的调节作用;以染色质免疫沉淀法检测Elk1-XAF1的DNA结合活性;以实时定量PCR检测Elk1 siRNA对XAF1 mRNA表达的影响。结果:Sulfone可显著抑制pERK1/2表达,显著上调XAF1表达。XAF1启动子Elk1结合序列点突变能显著增加Sulfone诱导的XAF1启动子转录活性,而c-ETS和IRF结合序列点突变对Sulfone诱导的XAF1启动子转录活性无明显影响。XAF1启动子区域存在Elk1的特异性结合序列。以Elk1 siRNA抑制Elk1表达能显著增高XAF1mRNA表达。结论:Sulfone通过抑制ERK1/2信号通路下游转录因子Elk1活性,在转录水平上调人结肠癌细胞XAF1表达。 展开更多
关键词 X连锁凋亡抑制蛋白相关因子1 转录因子 结肠肿瘤 sulfone
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Solid-phase Synthesis of Vinyl Sulfones Using Polystyrene-supported Selenomethyl Phenyl Sulfone
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作者 ShouRiSHENG WeiZHOU XiaoLingLIU QinXIN, CaiShengSONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期583-584,共2页
关键词 Solid-phase organic synthesis polystyrene-supported selenomethyl phenyl sulfone vinyl sulfone.
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A facile stereospecific synthesis of (Z)-2-sulfonyl-substituted 1,3-enynes via Sonogashira coupling of (E)-α-iodovinyl sulfones with 1-alkynes
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作者 Wen Yan Hao Jian Wen Jiang Ming Zhong Cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第7期773-776,共4页
(E)-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically af... (E)-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically afford the corresponding (Z)-2-sulfonyl-substituted 1,3-enynes 3 in high yields. 展开更多
关键词 (E)-α-Iodovinyl sulfone 1 3-Enynylsulfone Sonogashira coupling Terminal alkyne
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Sulfone通过抑制ERK途径上调XAF1表达诱导结肠癌细胞凋亡 被引量:2
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作者 卢君瑶 李薇薇 +2 位作者 徐琛莹 蔡劬 俞丽芬 《外科理论与实践》 2012年第5期459-462,共4页
目的:探讨化学预防药物Sulfone是否通过转录调节XAF1的表达诱导结肠癌细胞凋亡。方法:采用Hoechst 33258染色法检测人结肠癌细胞株HCT116(p53野生型)和SW480(p53突变型)经Sulfone处理后的细胞凋亡率。运用Western印迹法检测上述细胞经Su... 目的:探讨化学预防药物Sulfone是否通过转录调节XAF1的表达诱导结肠癌细胞凋亡。方法:采用Hoechst 33258染色法检测人结肠癌细胞株HCT116(p53野生型)和SW480(p53突变型)经Sulfone处理后的细胞凋亡率。运用Western印迹法检测上述细胞经Sulfone处理前后XAF1、磷酸化ERK1/2(p-ERK1/2)和ERK1/2总蛋白质的表达量变化。通过双重荧光素酶报告基因检测Sulfone对XAF1启动子转录活性的调节作用。结果:Sulfone能诱导HCT116和SW480细胞凋亡,其效应随剂量的增加和时程的延长而更明显。Sulfone能有效抑制上述两种细胞中ERK1/2蛋白的磷酸化(抑制率分别为74%和57%,P<0.05),但上调XAF1蛋白的表达(2.2倍和3.1倍,P<0.05)。经Sulfone处理后,XAF1启动子的转录活性在HCT116和SW480细胞分别提高了3.3倍(P<0.01)和2.6倍(P<0.05)。结论:Sulfone通过抑制ERK途径,在转录水平显著上调XAF1的表达进而诱导细胞凋亡,且这种作用的强弱与肿瘤细胞的p53分型有关。 展开更多
关键词 结肠癌 sulfone X连锁凋亡抑制蛋白相关因子1 凋亡
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Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone)for anion-exchange membrane 被引量:9
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作者 Xi Gao Jian Chun Yan +3 位作者 Hua Min Zhang Shou Hai Zhang Cheng Liu Ping Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第10期1269-1272,共4页
Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chlorometh... Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chloromethylated regent. CMPPESK was soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc) and chloroform. Quaternized poly(phthalazinone ether sulfone ketone) (QAPPESK) was prepared from CMPPESK by quaternization. QAPPESK had excellent solvent resistance, which was only partly soluble in sulfuric acid (98%) and swollen in N,N-dimethylformamide (DMF). The vanadium redox flow battery (V-RFB) using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency. 展开更多
关键词 CHLOROMETHYLATION QUATERNIZATION Poly(phthalazinone ether sulfone ketone) Anion-exchange membrane Vanadium redox flowbattery
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Synthesis and characterization of novel poly(aryl ether sulfone ketone)s containing phthalazinone and biphenyl moieties 被引量:3
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作者 Li Hong Xiao Cheng Liu Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期227-229,共3页
A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were... A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were between 38,330 and 67,900. The glass transition temperatures (Tg) and 5% decomposition temperatures were ranged in 253-269 ℃ and 488-500 ℃, respectively, The structures of these copolymers were confirmed by FT-IR and ^1H NMR. Moreover, all the resultant copolymers were amorphous determined by wide angle X-ray diffraction (WAXD). 展开更多
关键词 Poly(aryl ether sulfone ketone) PHTHALAZINONE BIPHENYL Thermal property Solubility
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THERMAL DEGRADATION OF POLY(ARYLENE SULFIDE SULFONE)/NMETHYLPYRROLIDONE CRYSTAL SOLVATE 被引量:3
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作者 杨杰 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第1期85-91,共7页
The thermal degradation of poly(arylene sulfide sulfone)/N-methylpyrrolidone (PASS/NMP) crystal solvate was studied by thermogravimetric analysis (TGA) and was compared with pure PASS in order to determine the w... The thermal degradation of poly(arylene sulfide sulfone)/N-methylpyrrolidone (PASS/NMP) crystal solvate was studied by thermogravimetric analysis (TGA) and was compared with pure PASS in order to determine the way in which the formation of the crystal solvate affected the thermal properties of the polymer. The activation energy of the solid state process was determined using Kissinger's method, which does not require knowledge of the reaction mechanism (RM), to be 174.18 kJ/mol which was lower than that for pure PASS (E = 214 kJ/mol). The study of master curves together with interpretation of integral methods, allows confirmation that the thermal degradation mechanism for PASS in the crystal solvate system is a decelerated Rn type, which is a solid-state process based on a phase boundary controlled reaction, in the conversion range considered. Whereas, the pure PASS follows a decelerated Dn thermodegradation mechanism in the same conversion range. 展开更多
关键词 Poly(arylene sulfide sulfone Crystal solvate Thermal degradation Thermogravimetric analysis (TGA).
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Allyl-containing Poly(aryl ether sulfone): Synthesis and Crosslinking 被引量:3
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作者 YU Yun-wu XING Yan GUO Mei-mei LIU Bai-jun JIANG Zhen-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期520-523,共4页
A novel type of crosslinkable poly(aryl ether sulfone)(PAES) bearing an allyl pendant(PES-OAllyl) was synthesized by a grafting reaction of hydrophenyl-containing PAES(PES-OH) and allyl bromide. PES-OH was pre... A novel type of crosslinkable poly(aryl ether sulfone)(PAES) bearing an allyl pendant(PES-OAllyl) was synthesized by a grafting reaction of hydrophenyl-containing PAES(PES-OH) and allyl bromide. PES-OH was prepared by a demethylation reaction of a methoxyphenylated PAES(PES-OCH3) in the presence of pyridine/hydrochlo- ride. The PES-OCH3 was synthesized by an aromatic nucleophilic substitution of bis(4-chlorophenyl)sulfone and (p-methoxy)phenylhydroquinone. Both DSC and solubility investigation were used to study the crosslinking behavior of PES-OAllyl. After heat treatment, the glass transition temperature(Tg) value of PES-OAllyl sharply increased from 165 ℃ to 227 ℃. Meanwhile, PES-OAllyl changed from a soluble polymer to an insoluble thermoset. In addition, TGA(thermogravimetric analysis) result suggests that the thermal stability of the crosslinked product was improved. All the data prove that the crosslinked PES-OAllyl could be a potential solvent-resistance high-performance material. 展开更多
关键词 CROSSLINKABLE Grafting reaction Poly(aryl ether sulfone
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A novel method for the management of sulfone-rich waste produced in the oxidative desulfurization(ODS) process 被引量:1
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作者 Sobhan Farahani Mohammad Amin Sobati 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第9期2447-2456,共10页
The oxidative desulfurization(ODS) process is one of the new desulfurization processes for the production of clean fuels. Despite the benefits of the ODS process, this process faces several important challenges. One o... The oxidative desulfurization(ODS) process is one of the new desulfurization processes for the production of clean fuels. Despite the benefits of the ODS process, this process faces several important challenges. One of the most important challenges of this process is the management of a waste which is rich of sulfone compounds.In the present study, a new strategy which is the addition of waste to the bitumen with other solid waste such as high density polyethylene(HDPE) waste has been investigated. The experimental design method was applied to investigate the effect of addition of the sulfone and HDPE wastes to the properties of the bitumen blends including degree of penetration, softening point, and mass loss. It was found that the sulfone waste can be added to the bitumen as a softener. The results showed that several grades of bitumen including 50/60, 60/70, 85/100 can be produced through the addition of sulfone waste along with the HDPE waste to the base 60/70 bitumen.In general, the application of simple processes such as mixing the wastes with the bitumen can reduce the cost of waste management, considerably. 展开更多
关键词 OXIDATIVE desulfurization Waste management sulfone waste BITUMEN Experimental design High density polyethylene(HDPE)waste
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Cyclic Oligomers of Phenolphthalein Polyarylene Ether Sulfone (Ketone): Preparation Through Cyclo-depolymerisation of Corresponding Polymers 被引量:1
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作者 HongHuaWANG JinYingDING TianLuCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第11期1377-1379,共3页
Cyclic oligomers of phenolphthalein polyarylene ether sulfone(ketone) were prepared through cyclo-depolymerisation of corresponding polymers using CsF as the catalyst in dipolar aprotic solvent DMAc and DMF, and a fam... Cyclic oligomers of phenolphthalein polyarylene ether sulfone(ketone) were prepared through cyclo-depolymerisation of corresponding polymers using CsF as the catalyst in dipolar aprotic solvent DMAc and DMF, and a family of macrocycles containing from dimer up to at least heptamer were confirmed by GPC, HPLC and MALDI-TOF-MS. The yields of cyclics get as high as 86.3% and 87.9% respectively. 展开更多
关键词 Cyclic oligomer phenolphthalein polyether sulfone(ketone) cyclodepolymerisation cesium fluoride.
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Synthesis and Characterization of Ion-exchange Sulfonated Poly (ether sulfone) 被引量:1
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作者 Fan Xiu MENG Chun Qing ZHANG Lian LIU Yuan Yuan ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期447-448,共2页
N,N'-Bis(3-hydroxyphenyl)-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization... N,N'-Bis(3-hydroxyphenyl)-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization of this bisimide with 4,4'-difluorodiphenylsulfone and disodium 3,3'-disulfonate4,4'-difluorodiphenylsulfone gave ion-exchange sulfonated poly(ether sulfone). The structure of the title compound was characterized with H-NMR and its polymer was characterized with FT-IR. 展开更多
关键词 Bisimide ion-exchange polymer sulfonated poly(ether sulfone).
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α-AMIDOALKYLATION VIA SULFONES:TOWARDS THE SYNTHESIS OF ANT VENOM ALKALOIDS
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作者 Pei Qiang HUANG Xiang Su FEI and Hong ZHENG(Department of Chemistry, Xiamen University, Xiamen 361005) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第9期739-742,共4页
Abstract: We described the synthesis of two 5-substituted γ-lactams Ⅰand Ⅱ by sulfone-baaed α-amidoalkylation method. This constitiutes the formal synthesis of ant venom alkaloids 2 and 3 in racemic form. The key ... Abstract: We described the synthesis of two 5-substituted γ-lactams Ⅰand Ⅱ by sulfone-baaed α-amidoalkylation method. This constitiutes the formal synthesis of ant venom alkaloids 2 and 3 in racemic form. The key intermediate 18 for the chiral synthesis of 2 and 3 was prepared from new chiral sulfone 7 by the same method. 展开更多
关键词 ANT OF VENOM AMIDOALKYLATION sulfoneS SYNTHESIS VIA ALKALOIDS
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A Stereoselective Synthesis of Substituted Allyl Alcohol by Threecomponent Rection of Acetylenic Sulfone,Phenylselenomagnesium Bromide and Ketones
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作者 Mei Hua XIE, Lu Ling WU, Xian HUANGDepartment of Chemistry, Zhejiang University, Xi-xi Campus, Hangzhou 310028 Department of Chemistry, Anhui Normal University, Wuhu 241000 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期887-888,共2页
Phenylseleno and sulfonyl substituted allyl alcohols were synthesized stereoselectively by the three-component reaction of acetylenic sulfone, phenylselenomagnesium bromide and ketones in one-pot.
关键词 Acetylenic sulfone KETONE allyl alcohol stereoselectivity.
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Synthesis and Crystal Structure of a Cyano-bridged Bimetallic Complex K_3(TMS)_2(H_2O)_2Cr(CN)_6[TMS = Tetramethylene Sulfone]
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作者 CHENWei CHEYun-Xia ZHENGJi-Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第4期379-382,共4页
The cyano-bridged bimetallic complex K3(TMS)2(H2O)2Cr(CN)6 with three- dimensional microporous structure was synthesized and characterized. The title complex (C14H20CrK3N, Mr = 601.78) crystallizes in monoclinic, sp... The cyano-bridged bimetallic complex K3(TMS)2(H2O)2Cr(CN)6 with three- dimensional microporous structure was synthesized and characterized. The title complex (C14H20CrK3N, Mr = 601.78) crystallizes in monoclinic, space group C2/c with a = 14.357(4), b = 9.331(3), c = 19.180(6) ?, β = 96.754(5)o, V = 2551.6(13) ?3, Z = 4, Dc = 1.567 g/m3, μ(MoKα) = 1.141 mm-1, F(000) = 1228, the final R = 0.0440 and wR = 0.0990 for 1760 observed reflections (I > 2σ(I)). In the crystal, two [Cr(CN) ]3- units, four K+ ions and two oxygen atoms of two 6 TMS molecules are linked to form a sixteen-membered ring and an extended three-dimensional structure. 展开更多
关键词 crystal structure synthesis tetramethylene sulfone cyano-bridge
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Microwave-assisted synthesis of diaryl or aryl-alkyl sulfones without catalyst
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作者 Jiong Zou Feng Li Feng Gang Tao 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第1期17-20,共4页
The microwave-assisted coupling reaction of electrondeficient aryl halides with sulfinic acid salts through SNAr-based addition reactions within 5-30 min. No catalysts were required under our conditions.
关键词 Microwave sulfone SNAr-based addition reaction
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The Rheological and Extrusion Behaviour of Blends Based on Phenolphthalein Poly(ether-ether-sulfone)and Thermotropic Liquid Crystalline Polymer
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作者 DI Ying-wei D'AMORE Alberto +3 位作者 NICOLAIS Luigi ACIERNO Domenico NOBILE Rossella LI Bin-yao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第3期93-101,共9页
IntroductionInthelasttwodecades,particularatentionhasbeendevotedtousingthethermotropicliquidcrystalinepolyme... IntroductionInthelasttwodecades,particularatentionhasbeendevotedtousingthethermotropicliquidcrystalinepolymers(TLCP)asareinfo... 展开更多
关键词 Phenolphthalein poly(ether ether sulfone) Thermotropic liquid crystalline polymer BLEND Rheology
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Quantitative Structure-chromatographic Retention Relationship for Polychlorinated Dibenzothiophenes and Their Corresponding Sulfones
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作者 朱建清 王维 +2 位作者 许惠英 许晓路 邹建卫 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第11期1835-1844,共10页
Polychlorinated dibenzothiophenes(PCDTs)and their corresponding sulfone(PCDTO2)compounds are a group of important persistent organic pollutants.In the present study,geometrical optimization and subsequent calculations... Polychlorinated dibenzothiophenes(PCDTs)and their corresponding sulfone(PCDTO2)compounds are a group of important persistent organic pollutants.In the present study,geometrical optimization and subsequent calculations of electrostatic potentials(ESPs)on molecular surface have been performed for all 135 PCDTs and 135 PCDTO2 congeners at the HF/6-31G*level of theory.A number of statistically-based parameters have been extracted.Linear relationship between gas-chromatographic retention index(RI)and the structural descriptors have been established by multiple linear regression.The result shows that two descriptors derived from positive electrostatic potential on molecular surface,σ+^2 andπ,together with the molecular volume(Vmc)and the energy of the lowest unoccupied molecular orbital(ELUMO)can be well used to express the quantitative structure-retention relationship(QSRR)of PCDTs and PCDTO2.Predictive capability of the two models has been demonstrated by leave-one-out cross-validation with the cross-validated correlation coefficient(RCV)of 0.996 and 0.997,respectively.Furthermore,the predictive power of the models is further examined for the external test set.Correlation coefficients(R)between the observed and predicted RI values for the external test set are 0.997 and0.998,respectively,validating the robustness and good prediction of our model.The QSRR model established may provide again a powerful method for predicting chromatographic properties of aromatic organosulfur compounds. 展开更多
关键词 POLYCHLORINATED dibenzothiophene(PCDTs) polychlorodibenzothiophene sulfone(PCDTO2) molecular electrostatic potential(ESP) quantitative structure-retention relationship(QSRR)
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SYNTHESIS AND CHARACTERIZATION OF A NEW THERMOTROPIC LIQUID CRYSTALLINE POLYESTER-ETHER SULFONE
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作者 Yu Shan NI Yun Hui WANG Guang LI Xiao Ming JIN Meng Xian DING Changchun Institute of Applied Chemistry,Academia Sinica,Changchun 130022 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期125-128,共4页
A new aromatic thermotropic liquid crystalline polyester-ether sulfone(PEES)was prepared from 4,4-bis(4-hydroxyphenoxy)diphenyl sulfone(BHPDS),terephthalic acid(TPA)and p-hydroxybenzoic acid(P-HBA).Some factors that a... A new aromatic thermotropic liquid crystalline polyester-ether sulfone(PEES)was prepared from 4,4-bis(4-hydroxyphenoxy)diphenyl sulfone(BHPDS),terephthalic acid(TPA)and p-hydroxybenzoic acid(P-HBA).Some factors that affected melting viscosity of polymer such as prepolymerization reaction medium and post-polymerization etc,were discussed.The liquid crystalline properties were characterized by DSC,polarizing microscope with a hot stage and WAXD measurements. 展开更多
关键词 HBA TPA FIGURE SYNTHESIS AND CHARACTERIZATION OF A NEW THERMOTROPIC LIQUID CRYSTALLINE POLYESTER-ETHER sulfone
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SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP
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作者 Ying-nan Xuan Yan Gao +1 位作者 Yong Huang Xi-gao Jian Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou Institute of Chemistry Chinese Academy of Sciences, Guangzhou 510650 China Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China Department of Polymer Science, College of Chemical Engineering Dalian University of Technology, Dalian 116012, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第3期225-229,共5页
A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacem... A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3 to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction. 展开更多
关键词 poly(aryl ether sulfone ketone) synthesis active pendant group
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The facile insertion of β-keto sulfones to arynes:The direct preparation of polysubstituted ortho-keto benzyl sulfones
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作者 Jian Xue Lu Ling Wu Xian Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第6期631-633,共3页
One novel carbon-carbon bond insertion reaction of arynes has been developed. By this reaction β-keto sulfones can insert the triple bond of arynes to prepare polysubstituted ortho-keto benzyl sulfones.
关键词 ARYNES Insertion reaction C-C bonds β-Keto sulfones
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