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本文合成了两种三联吡啶修饰的萘酰亚胺化合物NPI1和NPI2,并利用紫外-可见吸收光谱(UV-Vis)、圆二色光谱(CD)、荧光共振能量转移(FRET)等方法研究了它们与双链CT DNA和Htelo G-四链体DNA的相互作用。实验结果表明,化合物NPI1和NPI2对G-四链体DNA具有很好的结合能力和选择性,溶液中的碱金属离子种类和萘酰亚胺基团上的取代基对NPI1和NPI2与DNA的作用有很大的影响。在含K+的缓冲液中,NPI2与G-四链体的结合常数达到1.06×108 L/mol,是与双链CT DNA结合常数的268倍。圆二色谱结果表明在不含碱金属离子的溶液中,NPI1和NPI2可诱导Htelo DNA形成反平行结构G-四链体。Autodock分子对接模拟表明NPI1和NPI2可以通过堆积作用、静电作用、氢键等作用方式与G-四链体结合,使得它们对G-四链体具有很高亲和性(Ka>107 L/mol)。 相似文献
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Katsuya Sakayori Yuji Shibasaki Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2005,43(22):5571-5580
A new high‐sensitive photo‐radical initiator, N‐[2‐(2‐acryloyloxyethoxy)ethyl]‐1,8‐naphthalimide (NI6), with good thermal stability based on naphthylimide derivative was developed. NI6 was prepared by the condensation of N‐[2‐(2‐hydroxyethoxy)ethyl]‐1,8‐naphthalimide and acryloyl chloride in the presence of 4‐dimethylaminopyridine. The film consisting of NI6 and pentaerythritol triacrylate (PETA) showed higher photosensitivity than those containing conventional photo‐radical initiators such as acrylic acid 2‐(2‐{2‐[2‐(4‐benzoyl‐phenoxy)‐ethoxy]‐ethoxy}‐ethoxy)‐ethyl ester, cyclohexylmaleimide, and the resulting film exhibited very high transmittance over 400 nm. The thermal stability of NI6 was very high and no decomposed residues were observed from the film consisting of NI 6 after heating at 250 °C for 1 h. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5571–5580, 2005 相似文献
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The photophysical characteristics of a polymerizable 1,8‐naphthalimide dye and its copolymer with styrene have been investigated. The functional properties of both low and high molecular weight fluorophores in the presence of different metal cations have been discussed with regard to their potential application as fluorosensors for the metal cations and protons. In acetonitrile solution the monomeric 1,8‐naphthalimide enhances its fluorescence emission in the presence of metal cations (Zn2+, Fe3+, Co2+, Pb2+, Cu2+, Ni2+, and Mn2+). In aqueous media the poly(St‐co‐MD) exhibits a selective response to Fe3+ cations. The monomeric and polymeric fluorophores also exhibit a considerable increase in their fluorescence intensity at acidic pH values (pH < 6) which suggest that they could be used as ON–OFF probes in analytical devices for signaling the presence of protons. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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A novel copolymer with naphthalimide pendant group was prepared, in which a tertiary amine acts as an electron donor and quenches the fluorescence of the 4‐amino‐1,8‐naphthalimide fluorophore via the photo‐induced electron transfer process. When a photoacid generator was added, fluorescence enhancement of the copolymer in the net film was induced, this would be applied to generate patterned fluorescent images. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Synthesis of a Naphthalimide Functionalized Calix[4]arene; A Host Type Fluorophore for Inclusion Compounds in Organic Medium 总被引:1,自引:0,他引:1
Izilda?A.?Bagatin Alexandre?T.?Cruz Henrique?E.?Toma Mário?J.?Politi Grégoire?J.?-F.?DemetsEmail author 《Journal of inclusion phenomena and macrocyclic chemistry》2005,52(3-4):189-193
This article reports the synthesis and the properties of 5,11,17,23-tetra(t-butyl)-25,27-bis-(ethoxy-1,8-naphthalimide)-26,28-hidroxy-calix[4]arene and the formation of an inclusion compound in organic medium. This functionalized calix[4]arene was conceived as the association of a potential host species with a good fluorophore for optical sensoring purposes. Calix[4]-NI as we will call it, maintains its ‘cone-pinched’ configuration and exhibits typical naphthalimide fluorescence bands in non-polar solvents. Its ability to interact with guest species via hydrogen bonding in its endo-hydrophilic cavity to form inclusion compounds was verified with absorption and fluorescence measurements using N-ethanol-1,8-naphthalimide as guest species, which was projected to fit exactly the host cavity and to interact with its naphthalimide π electrons. For this reason, it was possible to follow the formation of the inclusion compound with electronic spectroscopy.in final form: 17 November 2004.This revised version was published online in July 2005 with a corrected issue number. 相似文献
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Teresa Cristina de Barros Pedro Berci Filho Michel Loos Mario José Politi Hernan Chaimovich Iolanda Midea Cuccovia 《Journal of Physical Organic Chemistry》2011,24(5):385-397
The kinetics of hydrolysis of 1,8‐N‐butyl‐naphthalimide (1,8‐NBN) to 1,8‐N‐butyl‐naphthalamide (1,8‐NBAmide) and of 2,3‐N‐butyl‐naphthalimide (2,3‐NBN) to 2,3‐N‐butyl‐naphthalamide (2,3‐NBAmide), as well as the formation of the respective anhydrides from the amides were investigated in a wide acidity range. 1,8‐NBN equilibrates with 1,8‐NBAmide in mild alkali. Under the same conditions 2,3‐NBN quantitatively yields 2,3‐NBAmide. Over a wide range of acidities the reactions of the 1,8‐ and 2,3‐N‐butyl‐naphthalamides (or imides) yield similar products but with widely different rates and at distinct pH's. Anhydride formation in acid was demonstrated for 1,8‐NBAmide. The reactions mechanisms were rationalized in the manifold pathways of ab initio calculations. The differences in rates and pH ranges in the reactions of the 1,8‐ and 2,3‐N‐butyl‐naphthalamides were attributed to differences in the stability of the tetrahedral intermediates in alkali as well as the relative stabilities of the five and six‐membered ring intermediates. The rate of carboxylic acid assisted 1,8‐N‐Butyl‐naphthalamide hydrolysis is one of the largest described for amide hydrolysis models. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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In an attempt to obtain a model of copper(II) ion-selective sensors, a new 1,8-naphthalimide-based fluorescence chemosensor, N-allylamine-4-[(E)-4-(([2-aminoethyl]imino)methyl) benzene-1,3-diol]-1,8-naphthalimide (NABN), was designed and synthesized. The sensor NABN is fully characterized by melting point analysis, fourier transform infrared spectra, Ultraviolet–visible (UV–vis) spectra, fluorescence spectra, 1H NMR and 13C NMR spectroscopy, and mass spectrometry. NABN showed an unrivaled sensing behavior and an ardent selectivity toward copper(II) ion over other competitive metal ions tested in solution (N,N-Dimethylformamide (DMF)/Tris–HCl buffer, 1:1, v/v, pH = 7.2). The sensor showed a linear fluorescence quenching toward copper(II) ion in the range 0–50 μM, with a detection limit of 1.92 × 10−7 M estimated. Job's method indicated the formation of a 2:1 coordinative mode of the sensor with copper(II) ion with a high threshold of binding constant of 4 × 1012 M−1. Combining the above results, the quenching response of NABN toward Cu(II) ions could be ascribed to the strong, intrinsic paramagnetic behavior of Cu(II). 相似文献
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Selective and Sensitive Fluorescent Chemosensors for Cu2+ Ion Based upon Bis‐1,8‐naphthalimide Dyads
A series of new fluorescent chemosensors 5a – 5e , composed of two aminonaphthalimide fluorophores and 2,6‐bis((N‐aminoalkyl)aminocarboxy)pyridines, were prepared, characterized, and their fluorescent properties towards heavy and transition metal (HTM) ions were investigated. Chemosensors 5c – 5e exhibited high selectivity and sensitivity for Cu2+ ion over other HTM ions with fluorescent quenching (green to colourless). It clearly demonstrated that the length of the linkers (diamines) between the aminonaphthalimides and 2,6‐dicarboxypyridine of 5a – 5e was very important for their sensitivity and selectivity for Cu2+ ion over other HTM ions. 相似文献
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