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1.
A tandem one‐pot synthesis of polysubstituted 1,3‐thiazines has been developed by reacting with cyanoacetamide and isothiocyanate derivatives to give rise to 2‐cyano‐3‐mercaptoacrylamides, which are trapped in situ by various aldehydes or diversely substituted ketones through intermolecular cyclization, providing polysubstituted 1,3‐thiazine derivatives in short reaction times with good to excellent yields. The salient features of this novel protocol are operational simplicity, accessing the desired products from the readily available starting materials and easy of product isolation and may find wide spread applications in medicinal chemistry. 相似文献
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采用简单的葡萄糖辅助溶剂热合成法制备了碲化铅纳米棒。 利用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)、高分辨率透射电子显微镜(HRTEM)、能谱仪(EDS)等技术手段进行材料结构和形貌表征。 结果表明,产物是纯的立方相PbTe,纳米棒的直径约为50 nm,长500 nm左右。 研究了反应过程的影响因素及碲化铅纳米棒的形成机制。 产物的形貌受葡萄糖的量、反应时间、反应温度和聚乙烯吡咯烷酮(PVP)质量的控制,分析了形成这种结构的原因。 相似文献
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A mild and facile Wittig reaction between N‐substituted maleimides and aldehydes has been developed. Various synthetically valuable alkylidenesuccinimides were obtained from this one‐pot reaction in high yields (up to 99%). The product was obtained by simple filtration and no extra purification was necessary. Ethanol, an environment‐benign solvent, was found to be a suitable reaction medium. 相似文献
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Taku Sakaguchi Toyoharu Kobayashi Dr. Sho Hatano Hiroshi Tsuchikawa Dr. Koichi Fukase Prof. Dr. Katsunori Tanaka Dr. Shigeo Katsumura Prof. Dr. 《化学:亚洲杂志》2009,4(10):1573-1577
An efficient one‐pot synthetic procedure for the synthesis of 2,4‐disubstituted pyridines has been successfully established. The method proceeds through a 6π‐azaelectrocyclization‐aromatization sequence. Using this method, a wide variety of pyridine structures substituted at the 2‐position have been rapidly constructed from vinyl stannanes, vinyl iodide, sulfonamide, and a palladium catalyst. The method was further applied to the solid‐phase synthesis wherein the use of a “traceless” sulfonamide linker enabled the rapid preparation of a small library of pyridines with high purity, without any chromatographic separation. 相似文献
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Amplified Electrochemical Immunosensor for Calmodulin Detection Based on Gold‐Silver‐Graphene Hybrid Nanomaterials and Enhanced Gold Nanorods Labels 下载免费PDF全文
Ping Geng Ying Fu Meicheng Yang Qianqian Sun Kai Liu Xinai Zhang Zhiai Xu Wen Zhang 《Electroanalysis》2014,26(9):2002-2009
Calmodulin (CaM) is an important intracellular calcium‐binding protein. It plays a critical role in a variety of biological and biochemical processes. In this paper, a new electrochemical immunosensing protocol for sensitive detection of CaM was developed by using gold‐silver‐graphene (AuAgGP) hybrid nanomaterials as protein immobilization matrices and gold nanorods (GNRs) as enhanced electrochemical labels. Electrode was first modified with thionine‐chitosan film to provide an immobilization support for gold‐silver‐graphene hybrid nanomaterials. The hybrid materials formed an effective matrix for binding of CaM with high density and improved the electrochemical responses as well. Gold nanorods were prepared for the fabrication of enhanced labels (HRP‐Ab2‐GNRs), which provided a large capacity for HRP‐Ab2 immobilization and a facile pathway for electron transfer. With two‐step immunoassay format, the HRP‐Ab2‐GNRs labels were introduced onto the electrode surface, and produced electrochemical responses by catalytic reaction of HRP toward enzyme substrate of hydrogen peroxide (H2O2) in the presence of thionine. The proposed immunosensor showed an excellent analytical performance for the detection of CaM ranging from 50 pg mL?1 to 200 ng mL?1 with a detection limit of 18 pg mL?1. The immunosensor has also been successfully applied to the CaM analysis in two cancer cells (HepG2 and MCF‐7) with high sensitivity, which has shown great potency for improving clinic diagnosis and treatment for cancer study. 相似文献
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Unexpected One‐pot Synthesis of Novel 2‐Aminopyrimidine‐4‐ones under Microwave Irradiation 下载免费PDF全文
One‐pot, three‐component condensation of guanidine, ethylbenzoylacetate and various aromatic aldehydes in the presence of NaHCO3 have been investigated by microwave irradiation. The aromatic aldehydes bearing electron‐withdrawing groups undergo condensation with guanidine and ethylbenzoyl‐acetate to afford ethyl‐2‐amino‐4‐aryl‐1,4‐dihydro‐6‐phenylpyrimidine‐5‐carboxylate derivatives via Biginelli reaction. However, reaction of the aromatic aldehydes having electron‐releasing groups with guanidine and ethylbenzoylacetate did not give the corresponding dihydropyrimidines. Instead, novel 2‐amino‐5‐benzoyl‐5,6‐dihydro‐6‐arylpyrimidine‐4(3H)‐ones were obtained via an unexpected mechanism. 相似文献
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Jian Yang Prof. JunJun Peng Qingbo Zhang Dr. Feng Peng Prof. Hongjuan Wang Dr. Hao Yu Dr. 《Angewandte Chemie (International ed. in English)》2009,48(22):3991-3995
Turing lead into gold : Hollow hybrid PbSx–Au nanostructures of about 10 nm in diameter were synthesized using a one‐step reaction under mild experimental conditions. The redox reaction of gold precursors with PbS nanocrystals in the presence of dodecylamine leads to the hollow feature of hybrid nanostructures (see picture).
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Yi Gong Qing Lin Liu Ai Mei Zhu Qiu Gen Zhang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(12):2702-2708
One‐pot synthesis of thermoresponsive magnetic composite microspheres with a poly(N‐isopropylacrylamide) (PNIPAM) shell and a Fe3O4 core is demonstrated. Temperature sensitivity of PNIPAM was adopted to design the novel synthesis pathway. The as‐prepared composite microspheres have an obvious core‐shell structure with a mean size of approximately 250 nm. The Fe3O4 core is approximately 5 nm and the thickness of the PNIPAM shell is approximately 10 nm. The content of Fe3O4 in the composite microspheres can be controlled by this method. The composite microspheres experience a swelling and shrinking process in water by adjusting the temperature below and above the lower critical solution temperature (LCST) around 32 °C. These microspheres also show fine response to an external magnetic field. This work presents a platform to synthesize organic/inorganic composite microspheres in a facile and efficient approach. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2702–2708 相似文献
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Liya Zhang Chunmei Song Jiahui Yu Dan Yang Meiran Xie 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):5231-5238
Shell‐functionalized polymeric nanoparticle was prepared through the method of polymerization‐induced self‐assembly of block copolymers [poly(2,3‐bis(2‐bromoisobutyryloxymethyl)‐5‐norbornene)‐block‐poly(7‐oxanorborn‐5‐ene‐exo‐exo‐2,3‐dicarboxylic acid dimethyl ester), PBNBE‐b‐PONBDM] via one‐pot ring‐opening metathesis polymerization of 2,3‐bis(2‐bromoisobutyryloxymethyl)‐5‐norbornene (BNBE) and 7‐oxanorborn‐5‐ene‐exo‐exo‐2,3‐dicarboxylic acid dimethyl ester (ONBDM) in a selective solvent. The compositions and the molecular weights of the copolymers were estimated by 1H‐NMR and gel permeation chromatography. The micelles were characterized by dynamic light scattering, transmission electron micrograph, and atomic force microscopy. The results indicated that the spherical micelles constructed with bromine‐bearing PBNBE shell and PONBDM core were stable and reproducible in toluene. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
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An efficient and environmentally benign procedure for the reactions of three components condensation of salicylaldehyde and two different CH acids to give 2‐amino‐4H‐chromenes catalyzed by a series of basic‐functionalized ionic liquids was reported. The most possible reaction pathway was proposed for the first time by performing density functional theory (DFT) calculations. Both cation and anion of [Bmim]OH have a cooperative effect on the reaction. [Bmim]+ increases the electrophilicity of salicylaldehyde via intermolecular hydrogen bonds, while OH? deprives proton of two CH acids to strengthen their nucleophilic ability. 相似文献
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Shan Tang Yan‐Yan Si Zhi‐Peng Wang Kun‐Rong Mei Xin Chen Jing‐Yuan Cheng Dr. Ji‐Shen Zheng Prof. Dr. Lei Liu 《Angewandte Chemie (International ed. in English)》2015,54(19):5713-5717
Successive peptide ligation using a one‐pot method can improve the efficiency of protein chemical synthesis. Although one‐pot three‐segment ligation has enjoyed widespread application, a robust method for one‐pot four‐segment ligation had to date remained undeveloped. Herein we report a new one‐pot multisegment peptide ligation method that can be used to condense up to four segments with operational simplicity and high efficiency. Its practicality is demonstrated by the one‐pot four‐segment synthesis of a plant protein, crambin, and a human chemokine, hCCL21. 相似文献
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Isabelle Chaduc Wenjing Zhang Jutta Rieger Muriel Lansalot Franck D'Agosto Bernadette Charleux 《Macromolecular rapid communications》2011,32(16):1270-1276
The syntheses of amphiphilic block copolymers are successfully performed in water by chain extension of hydrophilic macromolecules with styrene at 80 °C. The employed strategy is a one‐pot procedure in which poly(acrylic acid), poly(methacrylic acid) or poly(methacrylic acid‐co‐poly(ethylene oxide) methyl ether methacrylate) macroRAFTs are first formed in water using 4‐cyano‐4‐thiothiopropylsulfanyl pentanoic acid (CTPPA) as a chain transfer agent. The resulting macroRAFTs are then directly used without further purification for the RAFT polymerization of styrene in water in the same reactor. This simple and straightforward strategy leads to a very good control of the resulting amphiphilic block copolymers.
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Prof. Peng Gao Longqiang Wang Ying Wang Prof. Yujin Chen Xiaona Wang Guoli Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(15):4681-4686
ZnO/ZnS heterostructured nanorod arrays with uniform diameter and length were synthesized from zinc substrates in a one‐pot procedure by using a simple hydrothermal method. Structural characterization by HRTEM indicated that the heterostructured nanorods were composed of parallel segments of wurtzite‐type ZnO and zinc‐blende ZnS, with a distinct interface along the axial direction, which revealed the epitaxial relationship, ZnO (10$\bar 1$ 0) and ZnS ($\bar 1$ 1$\bar 1$ ). The as‐prepared ZnO/ZnS nanorods showed only two green emissions at around 523 nm and 576 nm. We also found that the nanorods exhibited high sensitivity to ethanol at relatively low temperatures, owing to their smaller size and structure. 相似文献
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An efficient and environmentally friendly procedure for the one-pot synthesis of tetrahydropyrimidinones from aldehydes, β-diketones and urea/thiourea by using magnesium bromide as an inexpensive and easily available catalyst under solvent-free conditions was described. Compared with the classical Biginelli reaction conditions, this new method has the advantage of good to excellent yields (74%-94%) and short reaction time (45-90 min). The structure of the Biginelli reaction product from β-diketone, salicylaldehyde and urea has been proposed to possess an oxygen-bridge by cyclization (intramolecular Michael-addition). 相似文献
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A new class of pyrazolone derivatives has been isolated in good to excellent yields from the 2:1 condensation reaction between 3‐methyl‐1‐phenyl‐5‐pyrazolone and arylaldehydes in the presence of ionic liquid [HMIM]HSO4. The compounds were characterised by their IR, NMR spectra, MS and elemental analyses. The important features of the methodology are a wide application range of substrates, higher yields and shorter reaction time. 相似文献
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Multicomponent One‐pot Reactions Towards the Synthesis of Stereoisomers of Dipicolylamine Complexes 下载免费PDF全文
Sakthi Raje Sureshbabu Gurusamy Abhishek Koner Sonam Mehrotra Dr. Samson Jegan Jennifer Dr. Prema G. Vasudev Prof. Ray J. Butcher Dr. Raja Angamuthu 《化学:亚洲杂志》2016,11(1):128-135
Reported are multi‐component one‐pot syntheses of chiral complexes [M(LROR′)Cl2] or [M(LRSR′)Cl2] from the mixture of an N‐substituted ethylenediamine, pyridine‐2‐carboxaldehyde, a primary alcohol or thiol and MCl2 utilizing in‐situ formed cyclized Schiff bases where a C?O bond, two stereocenters, and three C?N bonds are formed (M=Zn, Cu, Ni, Cd; R=Et, Ph; R′=Me, Et, nPr, nBu). Tridentate ligands LROR′ and LRSR′ comprise two chiral centers and a hemiaminal ether or hemiaminal thioether moiety on the dipicolylamine skeleton. Syn‐[Zn(LPhOMe)Cl2] precipitates out readily from the reaction mixture as a major product whereas anti‐[Zn(LPhOMe)Cl2] stays in solution as minor product. Both syn‐[Zn(LPhOMe)Cl2] and anti‐[Zn(LPhOMe)Cl2] were characterized using NMR spectroscopy and mass spectrometry. Solid‐state structures revealed that syn‐[Zn(LPhOMe)Cl2] adopted a square pyramidal geometry while anti‐[Zn(LPhOMe)Cl2] possesses a trigonal bipyramidal geometry around the Zn centers. The scope of this method was shown to be wide by varying the components of the dynamic coordination assembly, and the structures of the complexes isolated were confirmed by NMR spectroscopy, mass spectrometry, and X‐ray crystallography. Syn complexes were isolated as major products with ZnII and CuII, and anti complexes were found to be major products with NiII and CdII. Hemiaminals and hemiaminal ethers are known to be unstable and are seldom observed as part of cyclic organic compounds or as coordinated ligands assembled around metals. It is now shown, with the support of experimental results, that linear hemiaminal ethers or thioethers can be assembled without the assistance of Lewis acidic metals in the multi‐component assembly, and a possible pathway of the formation of hemiaminal ethers has been proposed. 相似文献