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101.
Eleven triazolyl substituted tetrahydrobenzofuran derivatives were synthesized in high yields as novel H+/K+‐ATPase inhibitor via one‐pot CuI‐catalyzed three‐component click reaction of azide, secondary amine and 3‐bromopropyne under mild conditions in water. Their structures were characterized by NMR, IR, ESI‐MS, elemental analysis and single‐crystal X‐ray diffraction analysis. Most of the target compounds exhibited better H+/K+‐ATPase inhibitory activity than commercial omeprazole with IC50 values less than 15 µmol·L?1. The initial structure‐activity analysis suggested that the triazole substituted by cycloalkyl, aromatic ring or O‐containing side‐chain seemed to be beneficial for enhancing the activity. 相似文献
102.
Bao-Lei Wang Qing-Nan Li Yi-Zhou Zhan Li-Xia Xiong Shu-Jing Yu Zheng-Ming Li 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):483-491
Abstract A novel series of pyrazole derivatives containing substituted phenylsulfinyl/sulfonyl group have been synthesized via the oxidation of intermediate pyrazole sulfoether with H2O2 in acetic acid. The novel compounds were characterized by melting point, 1H NMR, FT-IR, MS, and elemental analysis or HRMS. The biological activity results showed that most of the title compounds exhibit significant fungicidal activities against Alternaria solani Sorauer, Phytophthora capsici, and Corynespora cassiicola. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
103.
Athianna Muthusamy Krishnasamy Balaji Salem Chandrasekaran Murugavel 《Journal of polymer science. Part A, Polymer chemistry》2013,51(8):1707-1715
A series of poly(benzylidene‐ether)esters containing a photoreactive benzylidene chromophore in the main chain were synthesized from 2,6‐bis(4‐hydroxy‐3‐methoxybenzylidene)cyclohexanone (BHMBCH) with various aliphatic and aromatic diacid chlorides by an interfacial polycondensation technique. The intrinsic viscosity of the synthesized homo and copolymers determined by Ubbelohde viscometer was found to be 0.12 to 0.17 dL/g. The molecular structure of the monomer and polymers was confirmed by FT‐IR, 1H NMR, and 13C NMR spectral analyses. These polymers were studied for their thermal stability and photochemical properties. Thermal properties were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). It was found that the polymers were stable up to 280 °C and start degrading thereafter. Increase in acid methylene spacer length decreased the thermal stability. The self‐extinguishing property of the synthesized polymers was studied by calculating the limiting oxygen index (LOI) value using a Van Krevelen's equation. The influence of the length of methylene spacer on phase transition was investigated using DSC and odd‐even effect has been observed. Hot‐stage optical polarizing microscopic (HOPM) study showed that most of the polymers exhibited birefringence and opalescence properties. The photolysis of liquid crystalline poly(benzylidene‐ether)esters revealed that α,β‐unsaturated ketone moiety in the main chain dimerises through 2π + 2π cycloaddition reaction to form a cyclobutane derivative and leads to crosslinking. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
104.
Tanmoy Dutta Yong Li Aaron L. Thornton Da‐Ming Zhu Zhonghua Peng 《Journal of polymer science. Part A, Polymer chemistry》2013,51(18):3818-3828
Donor‐acceptor conjugated polymers containing a new imide‐functionalized naphthodithiophene (INDT) as the acceptor unit and a 2,2'‐bithiophene with varied substituents as the donor unit have been synthesized. The bandgaps of these polymers depend strongly on the dihedral angle of the 2,2'‐bithiophene unit. The 3,3'‐dialkoxy substitution (polymers PDOR / PBOR ) leads to near planar bithiophene conformation due to the well‐known S–O short contact, while the 3,3'‐dialkyl substitution (polymer PDR ) results in significant twisting due to the steric effect. Consequently PDOR / PBOR shows the lowest bandgap of 1.82/1.85 eV while PDR has a bandgap of 2.38 eV. Bulk‐heterojunction solar cells of the polymer/fullerene blends have been fabricated. Preliminary results show that PBOR gives the best device performance with power conversion efficiencies as high as 2.45% in air without any thermal annealing treatment, indicating the promising potential of INDT‐containing conjugated polymers for efficient solar cells. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3818–3828 相似文献
105.
Ching Hsuan Lin Yu Ren Feng Kang Hong Dai Hou Chien Chang Tzong Yuan Juang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(12):2686-2694
A phenolic OH‐containing benzoxazine ( F‐ap ), which cannot be directly synthesized from the condensation of bisphenol F, aminophenol, and formaldehyde by traditional procedures, has been successfully prepared in our alternative synthetic approach. F‐ap was prepared by three steps including (a) condensation of 4‐aminophenol and 5,5'‐methylenebis(2‐hydroxybenzaldehyde) (1) , (b) reduction of the resulting imine linkage by sodium borohydride, and (c) ring closure condensation by formaldehyde. The key starting material, (1) , was prepared from 2‐hydroxybenzaldehyde and s‐trioxane in the presence of sulfuric acid. F‐ap is structurally similar to bis(3,4‐dihydro‐2H‐3‐phenyl‐1,3‐benzoxazinyl)methane ( F‐a, a commercial benzoxazine based on bisphenol F/aniline/formaldehyde) except for two phenolic OHs. The phenolic OHs can provide reaction sites with epoxy and 1,1'‐(methylenedi‐p‐phenylene)bismaleimide (BMI). The structure–property relationships between the thermosets of F‐ap /epoxy, F‐a /epoxy, F‐ap /BMI, and F‐a /BMI were discussed. Experimental data showed that thermosets based on F‐ap /epoxy and F‐ap /BMI provided much better thermal properties than those based on F‐a /epoxy and F‐a /BMI. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2686–2694 相似文献
106.
Joseph W. Rumer Sheng‐Yao Dai Matthew Levick Laure Biniek David J. Procter Iain McCulloch 《Journal of polymer science. Part A, Polymer chemistry》2013,51(6):1285-1291
Two novel dihydropyrroloindoledione (DPID)‐based copolymers have been synthesized in a two directional approach and characterized (gel permeation chromatography (GPC), ultraviolet‐visible (UV–vis), cyclic voltammetry, and computational models). These planar, broad absorption copolymers show promise for use in organic electronics, with deep energy levels and low bandgaps. The two‐directional Knoevenagel condensation used demonstrates the versatility of DPID as a useful yet underexploited conjugated unit. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
107.
Aiming at the synthesis of structurally altered glycopeptides to probe multivalency effects in carbohydrate recognition, a glyco-amino acid building block was prepared, carrying a bivalent carbohydrate branching unit. This new mannosylated lysine derivative was shown to be fully suitable for solid-phase peptide synthesis. 相似文献
108.
Vincent Besse Gabriel Foyer Rémi Auvergne Sylvain Caillol Bernard Boutevin 《Journal of polymer science. Part A, Polymer chemistry》2013,51(15):3284-3296
This article describes the synthesis of new cyclic compounds able to react with amines to get nonisocyanate polyurethanes (NIPUs). The contribution of the most studied five‐membered cyclic carbonate was compared to five‐membered cyclic dithiocarbonate analogous and to a six‐membered cyclic carbonate. Difunctional reactive species were obtained by a simple substitution reaction or an efficient thiol–ene coupling reaction. The products, obtained with high yields, were characterized by 1H NMR, 13C NMR, and Fourier tansform infrared spectroscopy analysis. The dicyclocarbonates were then used to synthesize NIPUs by step growth polymerization with several diamines. These materials exhibited glass transition temperatures from 19 to ?29 °C, molar mass from 1800 to 20,400 g mol?1, and a 20% mass loss temperature (Td = 20%) between 249 and 296 °C. Such materials are interesting candidates for coating applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3284–3296 相似文献
109.
《合成通讯》2012,42(24):3536-3545
AbstractA novel two-step amine persulfonylation method described here results in significantly higher yields of sulfonimide-based dendrimers as compared with formerly available procedures. This allowed the preparation of the fifth-generation sulfonimide-based dendrimer for the first time, on a 2?g scale. Dendrimers of fourth and fifth generations decorated with naphthyl groups after being spin-coated on a glass substrate were shown to form stable hydrophobic films as revealed by contact angle measurements. 相似文献
110.