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1.
Xiao-Zhong Fu Feng-Jie Jiang Yu Ou Sheng Fu Yu-Feng Cha Shun Zhang Zong-Yuan Liu Wen Zhou Ai-Min Wanga Yong-Lin Wang 《中国化学快报》2014,25(1):115-118
A series of mono L-amino acid ester, mono non-steroid anti-inflammation drug(NSAID), carboxylic ester derivatives of acyclonucleoside phosphonates were prepared by using a ‘‘one pot synthesis' ' method and their in vitro anti-HBV activity were evaluated in HepG 2.2.15 cells. Compound 9a exhibited more potent anti-HBV activity and lower cytotoxicity than those of adefovir dipivoxil with IC50 and selective index(SI) values of 0.48 mmol/L and 763.72, respectively. 相似文献
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Serkan Elçin Gülbanu Koyundereli Çılgı Özlem Özen Karakuş Hasalettin Deligöz 《Journal of Thermal Analysis and Calorimetry》2014,118(2):719-722
In the present study, thermal stabilities of five new family of azocalix[4]arene mono ethyl ester derivatives, 4a–e, were investigated using thermogravimetry, differential thermogravimetry, and differential thermal analysis methods. It was found that all compounds showed thermal stability up to 236 °C averagely. After this temperature, decomposition of compounds starts gradually. The decomposition routes of 4a–c compounds are similar and occur with two stages. Ester alkyl groups decompose and remove from the structure in the first stage. Second stage corresponds to rest of structure decomposition. The decomposition routes of the 4d–e compounds are different from the decomposition routes of the 4a–c compounds. These compounds include halogen, and decomposition reactions realize with three and four stages respectively. 相似文献
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Abstract A novel drug-polysaccharide conjugate with konjac glucomannan (KGM) as a drug carrier was fabricated through the esterification of ibuprofen (IBU), an anti-inflammatory drug, with KGM. The influences of the reaction conditions, such as the amount of ibuprofen acryl chloride, reaction time, reaction temperature, and the amount of catalyst, on the degree of substitution were investigated. KGM ibuprofen ester (KGM-IBU) was characterized by Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), solid-state 13C NMR, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). The hydrophobic structure of IBU in KGM-IBU was proven by the fluorescence emission spectra of pyrene. In addition, by using commercially available ibuprofen sustained-release capsules (IBU-SRC) as a control, the in vitro controlled release performance of KGM-IBU was evaluated. The cumulative release of IBU-SRC within 36?h was 94%, while that of KGM-IBU within 36?h was 77%. The results showed that KGM-IBU had better sustained-release performance without a burst release effect. The obtained products could be used as a potential biocompatible sustained-release drug delivery system. 相似文献
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Liquid-liquid extraction separation of iron(III) with 2-ethyl hexyl phosphonic acid mono 2-ethyl hexyl ester (PC-88A) in toluene has been studied. Quantitative extraction of iron(III) with 5 x 10(-3) M PC-88A in toluene is observed in the pH range 0.75-2.5. From the extracted complex species in the organic phase iron(III) was stripped with 1-4 M HNO(3), 1.5-4 M H(2)SO(4) and 1.5-4 M HCl, and later determined spectrophotometrically by thiocyanate method. Separation of iron(III) was carried out with some of the first transition metals in binary and multicomponent mixtures. This method was extended for the determination of iron in real samples. 相似文献
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Rosin glycerin ester and its bromide were prepared from natural renewable rosin, glycerin and liquid bromine which were first
subjected to an esterification reaction, followed by an addition reaction. Their structures were characterized by an infrared
(IR) spectrum and their thermal resistance was conducted with thermal gravity (TG) and differential scanning calorimetry (DSC).
It showed that the bromide in the rosin glycerin ester decomposed faster than the ester; hence it may be used as fire-resistant
material. 相似文献
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Masaki Hasegawa Tadashi Yurugi Satoru Namiki Takatoshi Shiobara Hachiro Nakanishi Fusae Nakanishi 《Journal of polymer science. Part A, Polymer chemistry》1981,19(6):1291-1299
The photopolymerization behavior of p-phenylene diacrylic acid dimethyl ester (p-PDA Me) crystal and the thermal behavior of the resultant poly-p-PDA Me were investigated. From the kinetic study of polymerization at various temperatures a topochemical process via a stepwise mechanism was observed. Continuous change from monomer to polymer crystals was demonstrated by x-ray diffraction pattern and DSC analysis. Crystallinity of the reacting phase was maintained at an extremely high degree during the polymerization process in support of monomer crystal lattice control. Thermal study on as-polymerized poly-p-PDA Me crystal confirmed that the thermal reaction was a polymer crystal lattice-controlled depolymerization, which was followed by miscellaneous processes that involved vaporization, sublimation, and deterioration of the oligomeric or monomeric units of p-PDA Me. Thermal stability was dependent on the molecular weight. All the results are compared with those of four-center-type photopolymerization in the crystalline state. 相似文献
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《Comptes Rendus de l''Academie des Sciences Series IIB Mechanics Physics Astronomy》2001,4(4):309-314
The behaviour of N,N-diisopropyl-2-aminoethyl p-fluorobenzene thiosulfonate 3, which may be considered as a weakly toxic chemical analogue of VX agent, was investigated against oxidising agents. As VX 1, this compound exhibits the same tendency to give S–S bond cleavage. Its degradation by Curox® shows the formation of the N-oxide 6 which subsequently gives the sulfonate 7 by hydrolysis. The action of hydrogen peroxide, with or without boric acid, leads to the sulfinate 4 by S-S bond cleavage. Its oxidation gives sulfonate 7. Finally, reactions of MMPP and m-CPBA afford sulfonate 7 but no intermediates are highlighted with these reagents. 相似文献
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利用直链淀粉与甘/丙氨酸乙酯共取代聚膦腈交联, 制得了一种具有网络结构的新型杂化材料. 实验结果表明, 淀粉衍生物上的羟基转变为醇钠后, 可与聚膦腈分子链上的P-Cl键发生亲核取代反应; 所得聚合物膜无明显相分离, 力学性能优于具有相似组成的直链淀粉/聚膦腈共混膜, 表面亲水性和吸水率与对应的共混膜接近, 且均高于纯聚膦腈膜. 因此, 该聚合物可作为杂化生物材料用于药物控制释放和组织工程方面的研究. 相似文献
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J. H. Griffith C. S. Marvel G. W. Hedrick Frank Magne 《Journal of polymer science. Part A, Polymer chemistry》1966,4(8):1993-2002
The preparation of vinyl 2,2-dimethyl-3-morpholinocarbonylcyclobutaneacetate, vinyl 2,2-dimethyl-3-piperidinocarbonylcyclobutaneacetate, and vinyl 2,2-dimethyl-3-di-n-butylaminocarbonylcyclobutaneacetate has been achieved by selective amination followed by vinyl interchange. Homopolymers and vinyl chloride copolymers containing 25 and 30 wt.-% of the vinyl esteramides were prepared and evaluated as nonrigid plastics. The vinyl esteramides incorporated in vinyl chloride copolymers did impart some plasticization, but their effect was far below the effect of added plasticizer to a vinyl chloride polymer. 相似文献
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N. S. Prostakov L. A. Gaivoronskaya S. K. Sarkar V. F. Zakharov N. M. Durbazheva 《Chemistry of Heterocyclic Compounds》1986,22(7):710-713
It has been established that the reaction of 9-(p-methoxyphenylimino)fluorene with dichlorocarbene (conditions of phase-transfer catalysis) proceeds in two directions — the formation of spiroaziridinefluorene and of spiroindoxylfluorene, the structure of which has been demonstrated. Opening of the aziridine ring of spiroaziridinefluorene has been accomplished. From the analagous azamethine, 4-aza-fluorene, an ester of N-substituted -aminopropionic acid with a 4-azafluorene fragment was obtained by alkylation of its dianion with methyl chloroacetate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 895–897, July, 1986. 相似文献
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Wei Wang Li Yuan Guozheng Liang Aijuan Gu Jianyuan Wu 《Colloid and polymer science》2010,288(7):719-729
A novel kind of cyanate ester (CE)/epoxy resin microspheres have been synthesized using the polymerization technology of cyanate
ester and epoxy resin in anhydrous ethanol media; surfactant sodium dodecylbenzene sulfonate was used as an emulsifier, and
imidazole was used as catalyst or curing agent. The morphologies, chemical structures, and thermal properties of microspheres
were investigated by Fourier transform infrared spectroscopy, scanning electron microscope, laser scanning confocal fluorescence
microscopy, optical microscope, differential scanning calorimeter, and thermogravimetric analyzer, respectively. The effects
of process parameters such as the amount of imidazole and the weight ratio of epoxy resin to CE on the size and morphology
of microsphere were discussed. Results indicate that the reactivity and surface morphology of microsphere can be adjusted
by the amount of imidazole and the weight ratio of epoxy resin to CE. The prepared microsphere shows excellent thermal stability
and good reactivity. 相似文献
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A series of copper(II) thiosulfonate complexes have been prepared via the reaction of [Cu(Me 3tren)(OH 2)](ClO 4) 2 (Me 3tren = tris(2-methylaminoethyl)amine) with three thiosulfonate ligands (RSO 2S (-), where R = Me, Ph, and MePh) and characterized by microanalysis, FTIR spectroscopy, and X-ray crystallography. In these complexes, the distorted trigonal bipyramidal copper(II) coordination sphere is occupied by four amine nitrogen atoms from the tripodal tetramine ligand and an apically bound sulfur atom from the thiosulfonate ligand. By using the tripodal tetramine ligand the oxidation of the thiosulfonate has been restricted, allowing the isolation of the complexes. The Cu-S distances were found to be similar to those in related thiosulfate complexes, indicating coordinative interactions of similar strength. Two types of intramolecular hydrogen bonding interactions were evident which enhance the binding of the thiosulfonate to the copper(II) center. These interactions, which involve two amine N-H groups and either one or two thiosulfonate oxygens, were found to be weaker than in the corresponding thiosulfate complexes. The complex formation constants for the thiosulfonate complexes (log K f = 0.3-0.7) were found to be two orders of magnitude lower than compared to the thiosulfate analogues. This correlates well with a lower strength of intramolecular hydrogen bonding. 相似文献
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用2-乙基己基膦酸单(2-乙基己基)酯自硫酸溶液中萃取铟的机理研究 总被引:1,自引:0,他引:1
为了考察酸性磷类萃取剂化学结构上的差别对铟的萃取性能影响,本文研究了酸度对2-乙基己基膦酸单(2-乙基己基)酯[HEH(EH)P]萃取铟的影响,并与二(2-乙基己基)磷酸[HDEHP]进行比较;应用斜率法确定了萃取平衡反应;用饱和法制得了萃铟配合物,并测定了它们的红外光谱和核磁共振谱,在此基础上探讨了HEH(EH)P萃取铟的机理. 相似文献
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Novel glycidyl methacrylate–butyl acrylate–maleic anhydride (GBM) terpolymers with different molecular weights were synthesized by radical polymerization and characterized using fourier transform infrared, nuclear magnetic resonance (1H‐NMR and 13 C‐NMR), and gel permeation chromatography. Each GBM terpolymer was used to modify aluminum nitride (AlN), and the modified AlN, coded as AlN(GBM), was added to 2,2′‐bis(4‐cyanatophenyl)isopropylidene (CE) resin for preparing composites. Composites based on original AlN or γ‐(2,3‐epoxypropoxy)propyltrimethoxysilane‐modified AlN (AlN(K)) were also prepared for comparison. Although GBM and γ‐(2,3‐epoxypropoxy)propyltrimethoxysilane have similar reactive groups, the results indicate that GBM shows more attractive integrated advantages, reflected by the fact that CE/AlN(GBM) composites have better thermal stability, higher thermal conductivity, and higher glass transition temperature than those of CE/AlN(K). These properties result from better dispersion of fillers, improved interfacial adhesion between fillers and CE resin, and increased cross‐linking density. This study demonstrates that the nature of the coupling agents is an important factor to develop high performance composites for cutting‐edge industries. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Graphene oxide nanosheets (GONSs)/cyanate ester (CE) resin composites were prepared via a solution intercalation method. The structures of the GONSs and the composites were studied using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The mechanical and tribological properties of the composites were investigated. In addition, the thermal behavior of the composites was characterized by thermogravimetric analysis (TGA). Results show that the GONSs/CE resin composites were successfully prepared. The addition of GONSs is beneficial to improve the mechanical and tribological properties of the composites. Moreover, the composites exhibit better thermal stability in comparison with the CE resin matrix. 相似文献
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Diethyl bromodifluoromethyl phosphonate reacts readily with cadmium metal to form a stable cadmium complex. Depending on solvent, this functionalized organocadmium reagent exhibits stability for days to months. It reacts with a variety of electrophiles and serves as a synthetically useful source for the introduction of the difluoromethylene phosphonate group into organic compounds.The synthetic utility of a wide variety of fluoromethylene phosphonium ylides has been a major effort in our laboratory over the past several years [1]. The generation and capture of difluoromethylene ylides () as a general route to difluoromethylene olefins has been of especial interest to us [2]. In an effort to increase the nucleophilicity of the ylide, we have attempted to prepare the analogous phosphonate ylide (). Although we have achieved modest success [3] by capture of () in the reaction of sodium dialkyl phosphites with diethyl bromodifluoromethylphosphonate (), attempts to pregenerate (), either from diethyl difluoromethylphosphonate () or (), have met with little success. () appears to have minimal stability even at low temperatures, and scale up processes of synthetic value would seem to be difficult. 相似文献