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大位阻氨基酸Fmoc-Arg(Pbf)-OH与Rink Amide-AM树脂的高效缩合 被引量:2
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作者 朱亮亮 绳则翠 +3 位作者 周成 祝社民 陈英文 沈树宝 《现代化工》 CAS CSCD 北大核心 2012年第2期62-65,共4页
采用集自动搅拌、过滤、鼓泡等多重功能于一体的自制多肽固相合成反应器,以对称酸酐法、活化酯法、2,6-二氯苯甲酰氯(DCB)法研究了大位阻氨基酸Fmoc-Arg(Pbf)-OH与Rink Amide-AM树脂的连接反应工艺。探讨了催化体系、溶剂体系、反应时... 采用集自动搅拌、过滤、鼓泡等多重功能于一体的自制多肽固相合成反应器,以对称酸酐法、活化酯法、2,6-二氯苯甲酰氯(DCB)法研究了大位阻氨基酸Fmoc-Arg(Pbf)-OH与Rink Amide-AM树脂的连接反应工艺。探讨了催化体系、溶剂体系、反应时间、反应物配比以及搅拌方式对合成Fmoc-Arg(Pbf)-Rink Amide-AM树脂反应的影响。结果表明,采用活化酯法(DIC/HOBt/DMAP)时连接率最高,最佳反应条件为:在采用N2辅助磁力拌系统,以体积比为1∶1的DMA/DCM为反应溶剂,氨基酸与树脂物质的量的比为3∶1,反应时间为3 h时,连接率高达93%。 展开更多
关键词 女倚阳氧甚西务 糖霸酪 Rink amide-AM 树脂
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Copper-catalyzed amide bond formation from formamides and carboxylic acids 被引量:1
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作者 Hong-Qiang Liu Jun Liu +2 位作者 Yang-Hui Zhang Chang-Dong Shao Jing-Xun Yu 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第1期11-14,共4页
A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4.... A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4.0 equiv, formamides. 展开更多
关键词 amidES FORMamidES Carboxylic acids COPPER CATALYSIS
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天然产物Trichodermamide类似物的合成
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作者 宋健 林永成 陈荣礼 《精细化工》 EI CAS CSCD 北大核心 2012年第8期820-822,826,共4页
以8a-甲氧基-4,4a,5,8-四氢-1,2-苯并口恶嗪-3-羧酸乙酯(1a)为起始原料,经NaOH醇溶液和酸处理,在4-pyrrolidinopyridine和碳化双(环己基亚胺)(DCC)的存在下与3-氨基-7,8-二甲氧基香豆素(2)进行了酰胺化反应,合成了天然产物Trichodermami... 以8a-甲氧基-4,4a,5,8-四氢-1,2-苯并口恶嗪-3-羧酸乙酯(1a)为起始原料,经NaOH醇溶液和酸处理,在4-pyrrolidinopyridine和碳化双(环己基亚胺)(DCC)的存在下与3-氨基-7,8-二甲氧基香豆素(2)进行了酰胺化反应,合成了天然产物Trichodermamides的类似物T-1,总收率为61.6%,T-1通过了1HNMR,13CNMR,IR和元素分析等光谱学的结构表征;同时水解反应研究发现,含苯并口恶嗪双环结构的化合物1a可水解脱去酯基,而口恶嗪双环8a位上连有两个O的缩酮类似结构可稳定地保留。 展开更多
关键词 Trichodermamide类似物 水解反应 酰胺化反应 精细化工中间体
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Preparation of Hydrogel Based on Acryl Amide and Investigation of Different Factors Affecting Rate and Amount of Absorbed Water 被引量:1
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作者 Mostafa A. Radwan Omar H. Al-Sweasy Hany A. Elazab 《Agricultural Sciences》 2017年第2期161-170,共10页
Hydrogel is considered as an important material in our world nowadays as it is used in many important and significant applications such as in tissue engineering and agriculture. There are hundreds of types of such mat... Hydrogel is considered as an important material in our world nowadays as it is used in many important and significant applications such as in tissue engineering and agriculture. There are hundreds of types of such materials, where most of them can be easily prepared. The main objective of this work is to prepare one of the hydrogel types which could be very useful in the agriculture of deserts where plants in dry places require water in order to grow up. There are many places around the world where raining occurs only once or twice a year. There are also places where it does not rain at all. Therefore, hydrogels are required in order to absorb water in large quantities either during raining or irrigation instead of escaping to underground and then eject them to the roots of plants over time as the plants require watering. In this research a hydrogel based on acryl amide, Poly 2-Acrylamide-2-Methyl-1-Propane Sulphonic Acid, (PAMPS) was prepared by using different percentages of a suitable cross-linking agent, Methylene-bis-Acrylamide. The cross-linker content is very important factor affects the rate and amount of absorbed water. The highest amount of absorbed water at 25°C was observed by using 0.6% cross-linking agent based on monomer mass. The temperature of absorbed water and its pH value are also essential factors that affect the rate and the amount of absorbed water and were investigated in this work. The highest amount of absorbed water was recorded at pH = 12 and at 60°C. The amount and the rate of water absorbed by Sodium Polyacrylate Hydrogel were also investigated at 25°C. The agriculture applications of hydrogel based on Sodium Polyacrylate were examined using Fenugreek seeds implanting. 展开更多
关键词 HYDROGEL ACRYL amidE Poly 2-Acrylamide-2-Methyl-1-Propane Sulphonic Acid (PAMPS) Cross-Linking Agent Sodium POLYACRYLATE HYDROGEL
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NEW COHORT OF OPTICALLY ACTIVE NANOSTRUCTURE POLY(AMIDEIMIDE)S:PRODUCTION AND PROPERTIES
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作者 Shadpour Mallakpour Mehdi Hatami 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2011年第6期639-649,共11页
Novel aromatic-aliphatic poly(amide-imide)s containing chiral units in the main chain and hydroxyl benzamide units in the side chain have been obtained from the step-growth polymerization of 3,5-diamino-N-(4-hydrox... Novel aromatic-aliphatic poly(amide-imide)s containing chiral units in the main chain and hydroxyl benzamide units in the side chain have been obtained from the step-growth polymerization of 3,5-diamino-N-(4-hydroxyphenyl) benzamide (2) with different chiral diacid chlorides (la-le). Theoretical calculations were done by means of computational chemistry methods to narrate the stable conformation and orientation of each diacid chloride monomers under reaction conditions. These polymers were characterized by conventional techniques. The resulting polymers show good thermal stability. Other physical properties of polymers including crystallinity, inherent viscosity and morphological characteristics were also studied. 展开更多
关键词 Optically active poly(amide-imide)s Amino acid Benzamide units Nano scale.
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Amide-AlCl_(3)类离子液体催化苯与苯酐酰基化反应 被引量:4
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作者 王圆超 王桂荣 +2 位作者 闫云 赵新强 王延吉 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2022年第2期292-301,共10页
采用催化剂筛选和单因素实验及红外光谱、紫外光谱、拉曼光谱等表征手段,对Amide-AlCl_(3)类离子液体催化苯与苯酐(PHA)酰基化合成邻苯甲酰苯甲酸(BBA)的反应性能及机理进行了研究。结果表明,类离子液体N,N-二甲基乙酰胺-2AlCl_(3)(DMA-... 采用催化剂筛选和单因素实验及红外光谱、紫外光谱、拉曼光谱等表征手段,对Amide-AlCl_(3)类离子液体催化苯与苯酐(PHA)酰基化合成邻苯甲酰苯甲酸(BBA)的反应性能及机理进行了研究。结果表明,类离子液体N,N-二甲基乙酰胺-2AlCl_(3)(DMA-2AlCl_(3))为苯与苯酐酰基化反应的较优催化剂,其制备条件为n(AlCl_(3))∶n(DMA)=2∶1、100℃下反应3 h。DMA-2AlCl_(3)催化合成BBA反应的较优条件为n(Benzene)∶n(DMA-2AlCl_(3))∶n(PHA)=10∶2∶1、40℃、反应5 h,该条件下BBA收率达98.2%。DMA-2AlCl_(3)催化苯与苯酐酰基化反应机理为:DMA-2AlCl_(3)中的Al_(2)Cl_(7)^(-)进攻苯酐中的醚键氧及一个羰基氧得到酰基正离子;DMA-2AlCl_(3)中的[AlCl_(2)·n(DMA)]^(+)与苯环的π-环电子相互作用,使苯环上的π电子活化;酰基正离子作为亲电试剂进攻活化的苯环大π键,从而完成亲电取代反应生成BBA。 展开更多
关键词 amide-AlCl_(3) 类离子液体 苯酐 酰基化反应 邻苯甲酰苯甲酸
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L-theanine: A potential multifaceted natural bioactive amide as health supplement 被引量:8
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作者 Rajsekhar Adhikary Vivekananda Mandal 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第9期842-848,共7页
Natural bioactive compounds from plants are of great importance in modern therapeutics,which are used to prepare antibiotics, growth supplements or some other therapeutics. Ltheanine is such a bioactive amide amino ac... Natural bioactive compounds from plants are of great importance in modern therapeutics,which are used to prepare antibiotics, growth supplements or some other therapeutics. Ltheanine is such a bioactive amide amino acid presented in different plants and fungi,especially in tea. Theanine has influential effects on lifestyle associated diseases, such as diabetes, cardiovascular disorders, hypertension, stress relief, tumor suppression,menstruation and liver injury. This amino acid can maintain normal sleep and improve memory function and nullify effect of the neurotoxins. The rate of bioavailability and its medium of ingestion in the body is one of the great concerns for its additional antioxidant properties. Pharmacokinetics of the bioactive compound and its mode of action are described herewith. The biosynthesis and industrial synthesis are also reviewed to promote accelerated production of this bioactive compound in the pharmaceutical industries. 展开更多
关键词 Bioactive amide BIOAVAILABILITY L-THEANINE Lifestyle associated diseases PHARMACOKINETICS
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Synthesis of 2, 6-(substituded)pyridine Derivatives Using Amide and Imine Groups 被引量:9
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作者 Mei Ying LI, Pei Zhi HU*, Wan Ren ZHU, Kuo Xi XU College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第6期572-574,共3页
A new wo-armed?acyclic diamide Ia 2, 6-bis(1-ethanecarbozamido-2-amino)pyridine, and a new series of aromatic aldehyde schiff bases containing pyridine ring and amide bridge, IIa-f, were prepared. The compounds were... A new wo-armed?acyclic diamide Ia 2, 6-bis(1-ethanecarbozamido-2-amino)pyridine, and a new series of aromatic aldehyde schiff bases containing pyridine ring and amide bridge, IIa-f, were prepared. The compounds were characterized by elemental analysis, IR, 1HNMR and MS. The bioactivity half inhibitory concentration C1/2 is given. 展开更多
关键词 Aromatic aldehyde Schiff bases PYRIDINE amide bridge.
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Xbridge Amide色谱柱测定果糖注射液中果糖含量 被引量:7
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作者 陈华 《药物生物技术》 CAS CSCD 2012年第6期525-526,共2页
用Xbridge Amide色谱柱测定果糖注射液中果糖的含量.色谱柱为Xbridge Amide(waters,4.6 mm×150 mm,3.5μm),以乙腈-水-浓氨溶液(80∶20∶0.1)为流动相,示差检测器,柱温和检测器温度为40℃,流速为1.0 mL/min,进样量为20μL。果糖在... 用Xbridge Amide色谱柱测定果糖注射液中果糖的含量.色谱柱为Xbridge Amide(waters,4.6 mm×150 mm,3.5μm),以乙腈-水-浓氨溶液(80∶20∶0.1)为流动相,示差检测器,柱温和检测器温度为40℃,流速为1.0 mL/min,进样量为20μL。果糖在进样范围为50μg~150μg时线性关系良好,r=1。平均回收率为100.3%,RSD为1.4%(n=9)。本法简便、快捷、准确,灵敏度高,重复性好,可用于果糖注射液中果糖的含量测定。 展开更多
关键词 Xbridge amide色谱柱 果糖注射液
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Synthesis and Anti-tumor Activity of Novel Amide Derivatives of Ursolic Acid 被引量:9
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作者 LIU Dan MENG Yan-qiu +1 位作者 ZHAO Juan CHEN Li-gong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第1期42-46,共5页
Ursolic acid was modified at C3 and C28 position to obtain fourteen derivatives including twelve novel compounds, and their chemical structures were characterized by IR, ^1H NMR and MS. Cell growth inhibitory effects ... Ursolic acid was modified at C3 and C28 position to obtain fourteen derivatives including twelve novel compounds, and their chemical structures were characterized by IR, ^1H NMR and MS. Cell growth inhibitory effects of the derivatives against Hela cell were evaluated by MTT assay. All these derivatives were found to have stronger cell growth inhibitory than their parent compound, ursolic acid. The derivatives with a substituted acetyl group at C3 hydroxyl group show better activities than those with an unsubstituted hydroxyl group. 展开更多
关键词 Ursolic acid amide derivatives Anti-tumor activity
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Extraction of cobalt(Ⅱ) from aqueous solution by N,N'-carbonyl difatty amides 被引量:6
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作者 Emad A.Jaffar Al-Mulla Khalid Waleed S.Al-Janabi 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第4期469-472,共4页
The development of economic and environmentally friendly extractants to recover cobalt metal is required due to the increasing demand for this metal.In this study,solvent extraction of Co(Ⅱ) from aqueous solution u... The development of economic and environmentally friendly extractants to recover cobalt metal is required due to the increasing demand for this metal.In this study,solvent extraction of Co(Ⅱ) from aqueous solution using a mixture of N,N'-carbonyl difatty amides(CDFAs) synthesised from palm oil as the extractant was carried out.The effects of various parameters such as acid,contact time,extractant concentration,metal ion concentration and stripping agent and the separation of Co(Ⅱ) from other metal ions such as Fe(Ⅱ),Ni(Ⅱ),Zn(Ⅲ) and Cd(Ⅱ) were investigated.It was found that the extraction of Co(Ⅱ) into the organic phase involved the formation of 1:1 complexes.Co(Ⅱ) was successfully separated from commonly associated metal ions such as Fe(Ⅱ),Ni(Ⅱ),Zn(Ⅲ) and Cd(Ⅱ).Co(Ⅱ) stripping from the loaded organic phase was studied in aqueous solution.These results are useful to recover Co(Ⅱ) from aqueous solution utilising(CDFAs) as an extractant. 展开更多
关键词 N N'-Carbonyl difatty amides Solvent extraction Co(Ⅱ)
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Target-based design, synthesis and biological activity of new pyrazole amide derivatives 被引量:4
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作者 Xi-Le Deng Li Zhang +3 位作者 Xue-Ping Hu Bin Yin Pei Liang Xin-Ling Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第2期251-255,共5页
Based on the similarities in the conformation of VS008(N-(4-methylphenyl)-3-(tert-butyl)-1-(phenylmethyl)-1H-pyrazole-5-carboxamide) and BYIO6830(N'-(3,5-dimethylbenzoyl)-N'-tert-butyl-5-methyl-2,3-dihydr... Based on the similarities in the conformation of VS008(N-(4-methylphenyl)-3-(tert-butyl)-1-(phenylmethyl)-1H-pyrazole-5-carboxamide) and BYIO6830(N'-(3,5-dimethylbenzoyl)-N'-tert-butyl-5-methyl-2,3-dihydro-l,4-benzodioxine-6-carbohydrazide) bound to the active site of the EcR subunit of the ecdysone receptor(EcR)-ultraspiracle protein(USP) heterodimeric receptor,a series of new pyrazole amide derivatives were designed and synthesized.Their structures were confirmed by IR,~1H NMR,^(13)C NMR and elemental analysis.Results from a preliminary bioassay revealed that two of the pyrazole derivatives exhibited promising insecticidal activity.Specifically,compounds 6e and 6i exhibited good activity against Helicoverpa armigera(cotton bollworm) at low concentration.Symptoms displayed by tebufenozide-treated H.armigera were identical with those displayed by its treated counterpart.6i showed the same poisoning symptoms as those of tebufenozide.In addition,results from molecular docking result indicated that the binding modes of 6e and 6i at the active site of the EcR subunit of the heterodimeric receptor were similar to that of the bound tebufenozide. 展开更多
关键词 Molting hormone Pyrazole amide Rational design Bioactivity Molecular docking
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Measurement and Correlation for Solubility of (S)-(+)-2,2-Dimethyl-cyclopropane Carbox Amide in Different Solvents 被引量:3
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作者 石晓华 周彩荣 +1 位作者 高玉国 陈新志 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4X期547-550,共4页
(S)-(+)-2,2-dimethylcyclopropane carbox amide is a key intermediate of Cilastatin, an inhibitor of de- hydropeptidase-I. Its corresponding solid-liquid equilibrium data will provide essential support for industrial de... (S)-(+)-2,2-dimethylcyclopropane carbox amide is a key intermediate of Cilastatin, an inhibitor of de- hydropeptidase-I. Its corresponding solid-liquid equilibrium data will provide essential support for industrial design and further theoretical studies. The solubilities of (S)-(+)-2,2-dimethylcyclopropane carbox amide in toluene, di- chloromethane, trichloromethane, ethyl acetate, ethanol and pure water at different temperature were measured us- ing the synthetic method by a laser monitoring observation technique. The solubility data were correlated with the modified Apelblat equation. The calculated values were good in agreement with the experimental values. 展开更多
关键词 SOLID-LIQUID EQUILIBRIUM SOLUBILITY (S)-(+)-2 2-dimethylcyclopropane carbox amidE
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Design,synthesis and biological activity of novel substituted pyrazole amide derivatives targeting Ec R/USP receptor 被引量:4
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作者 Xi-Le Deng Jin Xie +6 位作者 Yong-Qiang Li De-Kai Yuan Xue-Ping Hu Li Zhang Qing-Min Wang Ming Chi Xin-Ling Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第4期566-570,共5页
In order to discover highly active ecdysone analogs, a series of new substituted pyrazole amide derivatives were obtained using structure-guided optimization method and further screened for their insecticidal activiti... In order to discover highly active ecdysone analogs, a series of new substituted pyrazole amide derivatives were obtained using structure-guided optimization method and further screened for their insecticidal activities, in the basis of the core structures of the two active compounds N-(3-methoxyphenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide(6e) and N-(4-(tert-butyl)phenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide(6i), previously presented by us. The chemical structures of the title compounds were identified by spectral analyses. The preliminary bioassay results indicated that one among the synthesized pyrazole derivatives, compound 34, endowed with good activity against Mythimna Separata at 10 mg/L, which was equal to that displayed by the positive control tebufenozide. In addition, examples of molecular docking and molecular dynamics studies demonstrated that 34 may be the potential inhibitor to Ec R and its docking conformation was similar to that of tebufenozide. In addition, increasing the hydrophobic effect and considering the suitable bulk effect on pyrazole ring are beneficial to the inhibiting activity to Ec R and activity in vivo. 展开更多
关键词 Moulting hormone Pyrazole amide Bioactivity Molecular docking Molecular dynamics simulation INSECT growth regulators
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Synthesis and biological evaluation of 12-benzyl matrinic amide derivatives as a novel family of anti-HCV agents 被引量:4
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作者 Sheng Tang Zong-Gen Peng +5 位作者 Xin Zhang Xin-Yue Cheng Wen-Jing Li Jian-Dong Jiang Ying-Hong Li Dan-Qing Song 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第7期1052-1057,共6页
A new series of 12-benzyl matrinic amide/ethanamide derivatives were synthesized from matrinine(1)and evaluated for their anti-HCV activity,taking compound 2 as the lead.SAR revealed that the introduction of a suita... A new series of 12-benzyl matrinic amide/ethanamide derivatives were synthesized from matrinine(1)and evaluated for their anti-HCV activity,taking compound 2 as the lead.SAR revealed that the introduction of a suitable substituent at the N’-end of matrinic amide might greatly enhance the potency.Among them,matrinic acid 17 and N’-substituted matrinic amides 18a-d exhibited promising potency with low micromolar EC50 values ranging from 1.03μmol/L to 7.54 μmol/L,and better therapeutic window with SI from 66 to 132.Moreover,compound 17 displayed an excellent PK and safety profile in vivo,demonstrating good drug-like characteristics.Thus,it has been selected for further investigation,with an advantage of decreased chances of inducing drug-resistance mutations. 展开更多
关键词 Matrinic acid Matrinic amide Hepatitis C virus Structure–activity relationship
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Synthesis of Novel Poly(aryl ether amide)s Containing the Phthalazinone Moiety 被引量:4
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作者 Lin CHENG~1 Xi Gao JIAN~2 (~1Department of Materials Science & Engineering, Wuhan Institute of Chemical Technology. Wuhan 430074) (Department of Polymer Science & Materials. DaLian University of Technology. DaLian 1 16012) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第4期307-310,共4页
Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one ... Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one were successfully synthesized from readily available heterocyclic bisphenol-like monomers in two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety were successfully prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. 展开更多
关键词 poly(aryl ether amide)s PHTHALAZINONE direct polymerization heterocyclic diamine
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Synthesis and Properties of Gemini Cationic Surfactants with Amide Spacers 被引量:3
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作者 DENGQi-gang YUHong-wei +3 位作者 LINHong JIALi-hua GUOXiang-feng ZHOUDe-rui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第3期337-339,共3页
Four gemini cationic surfactants {N,N′-di[2-(lauryldimethylamino)acetyl]polymethylenediamine dichloride, LAA-s-LAA, s=2,3,4,6} were synthesized by using four bis(α-chloroacetamide)s and N,N-dimethyllaurylamine, resp... Four gemini cationic surfactants {N,N′-di[2-(lauryldimethylamino)acetyl]polymethylenediamine dichloride, LAA-s-LAA, s=2,3,4,6} were synthesized by using four bis(α-chloroacetamide)s and N,N-dimethyllaurylamine, respectively. The molecular structures were characterized by means of IR, ~ 1H NMR, \{~ ~13 C NMR\} and MS, and the behavior of their aqueous solutions was studied. The critical micell concentrations(CMC) of LAA-s-LAA were one order of magnitude lower than that of dodecyltrimethyl ammonium chloride(DTAC). With the change of the length of spacer chain(s), their CMC values change, and CMC reaches the top value at s=4. 展开更多
关键词 Gemini cationic surfactant SYNTHESIS amide spacer Surface tension
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Amide Ionic Liquids(AILs)/L-Proline Synergistic Catalyzed Asymmetric Mannich Reactions 被引量:4
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作者 LIU Bao-you ZHAO Di-shun +1 位作者 XU Dan-qian XU Zhen-yuan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第2期163-168,共6页
Amide ionic liquids (MLs)/L-proline synergistic catalyzed Mannich reactions of isovaleraldehyde, methyl ketones, and aromatic amines were carried out in moderate to high yields ( up to 96% ) and high stereo select... Amide ionic liquids (MLs)/L-proline synergistic catalyzed Mannich reactions of isovaleraldehyde, methyl ketones, and aromatic amines were carried out in moderate to high yields ( up to 96% ) and high stereo selectivities ( 〉99% e. e. ). The products were easily isolated by extraction; and the catalyst system was readily recycled at least thrice without significant loss of efficiency. The scope of the substrates was studied and the interpretation of the manifest improvement of the reaction rates and enantio-selectivity of the novel catalyst system was speculated. 展开更多
关键词 amide ionic liquids (AILs) L-PROLINE Synergistic catalysis Mannich reaction Asymmetric synthesis β-Aminoketones
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An efficient method for the N-arylation of phenylurea via copper catalyzed amidation 被引量:2
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作者 Sandip N.Gavade Ravi S.Balaskar +3 位作者 Madhav S.Mane Pramod N.Pabrekar Murlidhar S.Shingare Dhananjay V.Mane 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第6期675-678,共4页
The coupling reaction of phenylurea with different functionalized aryl halides in the presence of air stable CuI,N,N-dimethylethylenediamine as a ligand,and K_3PO_4 as a base gives symmetrical and unsymmetrical diaryl... The coupling reaction of phenylurea with different functionalized aryl halides in the presence of air stable CuI,N,N-dimethylethylenediamine as a ligand,and K_3PO_4 as a base gives symmetrical and unsymmetrical diarylureas in relatively high yields.This method is milder than the palladium catalyzed arylation and avoids the use of toxic phosphine ligands. 展开更多
关键词 Copper catalyst UREA Aryl halides amidATION
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Synthesis and Evaluation of Aromatic DTPA-bis(amide)Gadolinium Complexes as Magnetic Resonance Imaging Contrast Agents 被引量:2
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作者 ZHUO Ren Xi WEN Jie WANG Lu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第2期58-64,共7页
Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spec... Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spectrophotometric method. The results show that the complexing properties of the ligands in comparison with those of DTPA are affected by converting two carboxyl groups to amide groups. The relaxation studies have shown that the relaxivity of the chelates is similar to that of Gd DTPA, indicating that in solution all the chelates have one water molecule directly coordinated to the metal ion. Only one water molecule in inner coordination sphere suggests the coordination of the carboxamide oxygen to gadolinium ion, which agrees with the FT IR results. 展开更多
关键词 SYNTHESIS Aromatic DTPA bis(amide) GADOLINIUM RELAXIVITY
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