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合成了对氨基苯乙酮缩对二甲氨基苯甲酰腙(AAPABH),采用荧光光谱法和UV-Vis吸收光谱法研究了AAPABH与DNA的相互作用。在pH 7.4Tris-HCl缓冲溶液中,以345 nm激发该化合物发射弱荧光,加入DNA后出现明显的荧光增强现象,表明探针分子与DNA结合形成了稳定配合物,其结合常数为5.48×107L/mol。研究了离子强度对体系荧光强度的影响,结果显示NaCl的加入未引起AAPABH-DNA体系荧光强度明显变化,表明AAPABH和DNA间不存在静电作用;同时DNA对AAPABH吸收光谱的影响表现为减色效应、探针分子与热变性后的DNA作用力明显小于与未变性DNA间的作用力、探针分子与溴化乙锭(EB)竞争结合DNA使得EB-DNA体系荧光猝灭,上述实验结果均表明探针分子主要以嵌插作用方式与DNA作用。 相似文献
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新显色剂对-二甲氨基偶氮氯膦的合成及其与钍显色反应的研究 总被引:2,自引:0,他引:2
合成了新显色剂对-二甲氨基偶氮氯膦,研究了它与Th(Ⅳ)的显色反应.结果表明:Th(Ⅳ)在0~30μg/25mL范围内与该试剂形成的配合物在674,612和538nm3个波长处吸光度绝对值之和与溶液中Th(Ⅳ)的浓度呈线性关系,故可利用该3个波长下吸光度绝对值叠加的方法测定Th(Ⅳ),其ε值达1.74×105L·mol-1·cm-1.由于显色反应在较强酸性介质中进行,本法有良好的选择性,大多数共存离子不干扰钍的测定,用于测定岩矿中的微量钍,结果满意. 相似文献
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设计合成阴离子受体是近年来超分子化学中一个颇为活跃的研究领域[1~ 7] .其中荧光法以其高灵敏度和高选择性等特点使发光受体的设计合成备受关注 [6 ,7] .分子内电荷转移 (Intramolecular charge transfer,ICT)原理已被成功地用于构筑阳离子荧光传感体系[8] ,但将其应用于阴离子识别的研究尚鲜见报道[9~ 12 ] .本文设计合成了 ICT荧光体对二甲氨Scheme 1 The structures of anion receptors基苯甲酰肼 (DMABH,结构见 Scheme 1 ) ,研究了 DMABH与阴离子如 HSO- 4,Ac O- ,H2 PO- 4,Cl O- 4,NO- 3,Cl- 和 Br- 等结合后的光… 相似文献
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综述了以对硝基苯甲酸为原料合成对氨基苯甲酸的近期研究进展。并从技术和经济角度讨论了各种合成方法的优点与不足。 相似文献
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毛细管电泳在拮抗药物对氨基苯甲酸、对羟基苯甲酸和磺胺分析测定中的应用 总被引:2,自引:0,他引:2
本文报道了一种用毛细管区带电泳法(CZE)分离与测定对氨基苯甲酸、对羟基苯甲酸及磺胺类药物的新方法.电泳条件为:用 20mmol/L硼砂-20mmol/L H_3PO_4-20 mmol/Lβ-环糊精-4%乙醇(pH 7.0)作电泳液,L-抗坏血酸为内标,280nm为检测波长,样品由电进样方式(10kV/10s)引入毛细管(51.2 cm×50μm i.d.,有效分离长度为 38.5 cm).在24.5°C下,6 min内三者可达基线分离(电泳电压 25kV),且在一定范围内可进行定量分析,保留时间(Tr)及A_(样品)/A_(内标)的RSD值分别小于1.0%和5.0%.本法的建立为研究这三者共存于高等动物及微生物体内时的生理作用提供了一种可共选择的新方法. 相似文献
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新显色剂2-(2-咪唑偶氮)-5-二甲氨基苯甲酸与镍(Ⅱ)的显色反应研究 总被引:2,自引:0,他引:2
研究了新显色剂2-(2-咪唑偶氮)-5-二甲氨基苯甲酸(IZDBA)与Ni(Ⅱ)的显色反应。结果表明,在pH 6.0的HAc-NaAc缓冲溶液中,IZDBA可与Ni(Ⅱ)形成一种配合比为2∶1的稳定红色配合物,其最大吸收波长位于580 nm处,而试剂的最大吸收波长为390nm,对比度为190 nm。配合物的表观摩尔吸光系数为2.95×104L.mol-1.cm-1;Ni(Ⅱ)量在0~0.8 mg/L范围内遵守比耳定律。在硫脲和氟化铵存在下,方法可直接用于测定镍催化剂和铸造铝合金中的微量镍。本法与原子吸收光谱法相对照,结果基本一致。 相似文献
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合成了二安替比林基-(对二甲氨基)苯基甲烷(DADM).在Mn(Ⅱ)和吐温-60存在下,Cr(Ⅵ)与DADM反应生成生色化合物,λ_(max)为550nm,ε为1.03×~5L·mol~(-1).cm~(-1)。Cr(Ⅵ)量在0~10μg/25ml间符合比尔定律。用于天然水和电镀废液中微量铬(Ⅵ)的测定,结果满意。 相似文献
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Two multiamide calix[4]arenes (5, 6) were synthesized and characterized by NMR, MS and elemental analysis. The binding properties
of receptors with some anions (π-O2NPhOPO32−, π-O2NPhO−, H2PO4−, Ac−, Cl−, Br− and I−) were studied by UV-Vis spectra. The results indicate that the tetraamide calix[4]arenes (5, 6) have a good selectivity to
the anions containing aromatic ring (π-O2NPhOPO3
2−, π-O2NPhO−). The 1 : 1 complexes between host and guest were formed through multiple hydrogen bonding and π-π interactions. The hosts
5 and 6 also show a definite binding ability for the anions (H2PO4−, Ac−, Cl−) that have no ultraviolet absorption, which provides a simple method of spectrum detection for these anions. 相似文献
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The synthesis and anion recognition properties of four novel [2]rotaxane host architectures containing additional alkyl functionality integrated within macrocyclic and axle components to shield the binding cavity from the solvent are described. The rotaxane species containing a tetra(methyl)-functionalised macrocycle component is found to be a weaker anion complexant than the equivalent unfunctionalised receptor, which is likely due to steric hindrance restricting the anion's access to the interlocked cavity. Rotaxane molecules containing tetra(methyl)-functionalised axle components are also investigated, and the additional alkyl functionality serves to enhance anion binding affinity and selectivity when incorporated within the axle's flexible ethylene linkages. Moreover, the equivalent unfunctionalised rotaxane displays a rare preference for oxoanions over chloride guest species. 相似文献
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LIU Shunying WANG Fajun WEI Lanhua XIAO Wang MENG Lingzhi & HE Yongbing Department of Chemistry Wuhan University Wuhan China 《中国科学B辑(英文版)》2004,(2)
~~Synthesis and anion recognition of neutral receptors based on multiamide calyx[4]arene~~ 相似文献
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设计合成了一种含双腙类阴离子受体1(5-甲基双水杨醛-2,4-二硝基苯腙)。用紫外-可见吸收光谱、荧光光谱考察了其与AcO-,H2PO4-,F-,Cl-,Br-和I-阴离子的作用。当加入AcO-、F-和H2PO4-时,受体分子1的吸收光谱发生明显的红移,与此同时溶液颜色由浅粉色变为紫色,而加入其他阴离子则无变化。通过在DMSO-d6核磁滴定实验进一步研究受体1和F-相互作用的本质。 相似文献
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The synthesis of simple, chromogenic pyridine-2,6-dicarboxylic acid amides, derivatives of isomeric nitroanilines and aminonitrophenols, and their ion binding properties are described. The ligands' response to ionic species was examined by naked eye and was studied with the use of UV–vis spectroscopy in DMSO and its mixture with water. The effect of the localisation and the type of the substituents in aromatic rings were discussed. 1H NMR experiments were carried out to probe the mechanism of anion recognition, i.e. complexation via hydrogen bond formation versus ligand deprotonation. A selective response of N,N′-bis(2-hydroxy-4-nitrophenyl)pyridine-2,6-dicarboxamide (L5) towards dihydrogen phosphate was found in both DMSO and DMSO–water (95:5) solvent mixture. The structure of N,N′-bis(2-hydroxy-5-nitrophenyl)pyridine-2,6-dicarboxamide (L4) was confirmed by X-ray crystallography. 相似文献
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Calix[4]arene-based receptors linked to amide and pyridine moieties have been synthesised in four steps from calix[4]arene, and characterised by 1H and 13C NMR spectroscopy. The recognition properties of these receptors towards different anions were evaluated using 1H NMR and computational studies. The receptors show modest selectivities towards dihydrogen phosphate versus carboxylates. 相似文献
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Esteban-Gómez D Platas-Iglesias C de Blas A Fabbrizzi L Rodríguez-Blas T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(19):5829-5838
In this paper, we report two macrobicyclic receptors containing pyridine head units derived from 1,10-diaza-15-crown[5] (L1) or 4,13-diaza-18-crown[6] (L2) that can be protonated in MeCN and used for anion recognition. The interaction of these protonated lateral macrobicycles with different anions has been investigated by means of spectrophotometric titrations in MeCN. The association constants for the complexes of halide anions with the protonated macrobicycles follow the sequences Cl(-)>Br(-)>I(-)>F(-) (L1) and Cl(-)>F(-)>I(-)>Br(-) (L2), whereby an increase of more than two logarithmic units is observed from F(-) to Cl(-) for the binding constants of the receptor derived from L1. The association constants also indicate an important degree of selectivity of these macrobicyclic receptors for Cl(-) over Br(-) or I(-). The X-ray crystal structure analyses of the chloride and bromide complexes confirms the formation of the envisaged supramolecular complexes. Moreover, the binding constants indicate that these receptors present a high sulfate-to-nitrate binding selectivity. The stability trend observed for the recognition of halide anions by the macrobicycles presented herein as well as the sulfate-to-nitrate binding selectivity have been rationalised by means of DFT calculations at the B3LYP/LanL2DZ level. These studies indicate that the especially high binding selectivity for Cl(-) is the result of the optimum fit between the protonated macrobicyclic cavity and the size of the anion, whereas the sulfate-to-nitrate selectivity results from shape complementarity between the hydrogen-binding acceptor sites on sulfate and the hydrogen-bond donors of the macrobicycle. 相似文献
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A colorimetric anion sensor 2,2′-(1E,1′E)-(thiophene-2,5-diylbis(methan-1-yl-1-ylidene)) was synthesized and characterized by various spectroscopic techniques. Anion binding studies were carried out using UV-visible spectrophotometric titrations and emission spectra studies, revealed that the receptor exhibits selective recognition toward F−over other anions. The selectivity for F−among the halides is attributed mainly to the hydrogen-bond interaction of the receptor with F−. Receptor 1 showed color change from fluorescent green to orange in the presence of tetrabutylammonium fluoride with 1:1 stoichiometry. Receptor 1 exhibits remarkably enhanced fluorescence intensity. 相似文献