罗丹明酰肼类荧光探针的合成及对Hg~(2+)的检测

基于金属离子诱导罗丹明螺内酰胺开环反应特性,合成了一种罗丹明酰肼类荧光探针分子RbH。在乙醇-水溶剂中,罗丹明酰肼探针与汞离子作用后吸收光谱出现明显的增强现象,溶液颜色由无色变为粉红;在580nm处探针溶液具有较强的红光发射,实现了对汞离子的裸眼定性分析和荧光半定量检测。     

水溶性大分子汞离子荧光-比色探针RhBH-P（VP-co-GMA）的合成与性能

采用活性基团修饰法,通过罗丹明B酰肼（RhBH）与乙烯基吡咯烷酮-甲基丙烯酸缩水甘油酯共聚物（P（VP-co-GMA））侧链上环氧基团的开环反应,制得一种键合有罗丹明B酰肼的水溶性聚合物RhBH-P（VP-co-GMA）。在水溶液中,该聚合物本身无色且无荧光,加入汞离子后,罗丹明的螺环结构打开,出现显著的荧光增强和颜色...     

水溶性大分子汞离子荧光-比色探针RhBH-P(VP-co-GMA)的合成与性能

采用活性基团修饰法,通过罗丹明B酰肼(RhBH)与乙烯基吡咯烷酮-甲基丙烯酸缩水甘油酯共聚物(P(VP-co-GMA))侧链上环氧基团的开环反应,制得一种键合有罗丹明B酰肼的水溶性聚合物RhBH-P(VP-co-GMA)。在水溶液中,该聚合物本身无色且无荧光,加入汞离子后,罗丹明的螺环结构打开,出现显著的荧光增强和颜色变红,实现了在水溶液中对汞离子的关-开荧光检测和裸眼检测。在此条件下,其他共存离子没有明显响应。研究表明:该聚合物是一种高选择性的Hg2+探针,可以实现水溶液中的汞离子检测。     

具有荧光增强性能的罗丹明B衍生物的合成及其对汞离子的检测

利用汞离子可以诱导罗丹明B衍生物的螺环结构发生开环反应并产生荧光增强效果这一特性,设计并合成了两种新型的荧光化学传感器2-噻吩甲醛罗丹明B酰肼(RhBTh)和苯甲醛罗丹明B酰肼(RhBAr),并研究了二者在汞离子检测中的应用.研究结果表明,RhBTh与RhBAr对汞离子均表现出非常好的荧光增强效果,检测过程中其它金属离子不会对检测结果产生明显的干扰.二者对汞离子的检测限分别为7.8 nmol/L和12.5 nmol/L.实验表明RhBTh和RhBAr对汞离子均具有良好的灵敏度和选择性.     

P(NIPAM-co-RhBHA)-NP的双重荧光响应行为与影响机制

以萘二甲酰亚胺与罗丹明B酰肼基硫脲两种有机荧光染料的光谱重叠特性, 及罗丹明B酰肼基硫脲在pH诱导下的可逆“开-闭”环反应为基础, 分别将其作为荧光共振能量转移(Fluorescence Resonance Energy Transfer, FRET)体系的供、受体, 并与聚N-异丙基丙烯酰胺(PNIPAM)的温敏特性相结合, 通过一系列化学反应, 合成了一种具有双重荧光刺激-响应特性的大分子P(NIPAM-co-RhBHA)-NP. 采用¹H NMR、FTIR、UV-vis和GPC对其结构进行了表征. 采用荧光光谱(PL)研究了缓冲溶液中该聚合物对环境温度和pH值的双重荧光响应行为, 并对其影响机制进行了探讨. 结果表明, 酸性条件下大分子中RhBHA和NP-NH₂之间会发生荧光共振能量传递; pH值和环境温度变化对大分子P(NIPAM-co-RhBHA)-NP的荧光发射具有显著影响.     

罗丹明6G酰肼Hg~(2+)荧光探针及细胞成像应用

合成了罗丹明6G酰肼并研究了各种金属离子对其吸收光谱和荧光光谱的影响,结果表明,罗丹明6G酰肼是一种高选择性汞离子荧光探针。在乙醇/4-羟乙基哌嗪乙磺酸缓冲溶液(pH=7.2,体积比1∶1)中,罗丹明6G酰肼本身无荧光,加入汞离子使其在554 nm产生强发射,发出明亮的黄绿色荧光。其他常见金属离子,包括重金属离子和过渡金属离子,对汞离子引起的荧光增强无影响。罗丹明6G酰肼还被用于活细胞中汞离子的检测。另外,汞离子能使罗丹明6G酰肼在530 nm产生强吸收,溶液由无色变为粉红色。     

基于荧光树状聚合物的高灵敏化学反应型汞离子传感器

以2,4-二氯苯硫酚为单体, 通过“一步法”合成了平均分子量为10.910 kD的荧光树状超支化聚苯硫醚(HPPS). 通过亲核取代和水解反应对HPPS进行了外围氨基修饰, 通过偶氮共价键使HPPS与氨基硫脲小分子相连, 制备出了高灵敏度树状聚合物基多位点反应型汞离子传感器. 基于汞离子与氨基硫脲脱硫关环反应和超支化聚苯硫醚对光信号的放大传递作用, 传感器对汞离子有灵敏的荧光响应信号, 线性范围为2.5～100 nmol/L, 检出限为0.46 nmol/L. 并利用分子模拟计算对反应识别机理进行了讨论.     

基于罗丹明荧光信号报告基团的细胞通透性铜离子荧光探针

分别以罗丹明B和罗丹明6G为荧光信号报告基团,以增强水溶性为目的的羟乙基肼为修饰基团,合成了反应型的Cu_(2+)离子选择性荧光探针分子L1和L2.紫外光谱和荧光光谱等分析结果表明,探针分子L1和L2对Cu_(2+)离子具有高灵敏度、高选择性的光谱识别行为.探针分子对Cu_(2+)离子的识别过程是通过Cu_(2+)离子催化水解控制氧杂蒽荧光信号的螺环酰肼基团实现荧光信号的开启,从而达到识别检测Cu_(2+)离子的目的,对Cu_(2+)离子的检出限均可达到10-8mol/L量级.同时,探针分子对常见金属离子和铵离子均具有较强的抗干扰能力.由于羟乙基肼的引入增强了探针的水溶性,使得探针L1和L2具有良好的细胞通透性和低毒性,实现了其对β-胰岛细胞(INS-1细胞)中Cu_(2+)离子的荧光成像检测.     

汞离子荧光、比色传感器

基于主客体识别的汞离子比色、荧光传感器由于使用方法简单、灵敏度高、不需要昂贵仪器等优势,受到了越来越多的关注。本文综述了近年来汞离子比色和荧光传感器的研究进展。本文根据作用机理将汞离子比色、荧光传感器分成三类,即通过特殊反应识别汞离子的传感器,通过配位作用识别汞离子的传感器以及基于纳米材料的汞离子传感器。其中通过特殊反应识别的传感器根据具体反应类型又可分成汞离子诱导的罗丹明上的内酰胺环开环型、汞离子与含硫(硒)的受体发生脱硫(硒)反应使受体氧化或关环型、汞离子与受体发生加汞化反应型和汞离子使受体发生汞离子催化的化学反应型这四类。本文对这些类型的汞离子传感器从设计原理、识别性能和机理等方面进行了介绍,并展望了该领域的研究方向。     

溶液中选择识别Hg(Ⅱ)的基于罗丹明的荧光传感器

设计合成了一种可在含水体系中选择性识别Hg²⁺的荧光传感器(化合物1),该化合物中同时包含了作为信号输出基团的罗丹明6G和作为键合基团的2-取代吡啶。其结构得到了¹H NMR,ESI-HRMS和单晶X-ray衍射分析的确认。在混合的水体系中,该化合物对二价汞离子表现出高选择性和高灵敏度的荧光和显色传感,体系的发光伴随着汞离子的加入而得以增强,颜色由无色变成粉红色。荧光滴定、ESI-HRMS和Job曲线分析都显示该传感器分子和汞离子形成1∶1的配合物。     

Naphthylthiourea-modified permethylcyclodextrin as a highly sensitive and selective "turn-on" fluorescent chemosensor for Hg2+ in water and living cells

A naphthylthiourea-modified cyclodextrin (1) and its urea derivative (2) were synthesized, and their fluorescence behaviors in the presence of various metal ions were investigated. Significantly, 1 showed a highly sensitive and selective fluorescence sensing ability for Hg(2+) over other metal ions in both water and living cells. That is, the addition of Hg(2+) to an aqueous solution of 1 gave a significantly enhanced fluorescence at ~380 nm. In contrast, the addition of other metal ions induced negligible fluorescence changes. The possible mechanism may be due to the transformation of thiourea to urea by Hg(2+)-induced desulfurization in water.     

Relation between intramolecular NH...S hydrogen bonds and coordination number in mercury(II) complexes with carbamoylbenzenethiol derivatives

A novel series of bis(carbamoylthiophenolato)mercury(II) complexes, [Hg(S-RNHCOC6H4)2] (1, R = 2-t-Bu; 2, R = 2-CH3; 3, R = 2-C6H5CH2; 4, R = 4-t-Bu), and a tetrakis(carbamoylthiophenolato)mercury(II) complex, (NEt4)2[Hg-(S-2-CH3NHCOC6H4)4] (5), were synthesized and characterized by 1H NMR, IR, 199Hg NMR, and crystallographic analyses. The bis(carbamoylthiophenolato)mercury complexes 1-3 do not have intramolecular NH...S hydrogen bonds between the amide NH group and the sulfur atom coordinated to mercury, whereas the tetrakis(thiophenolato)mercury complex 5 does have an intramolecular NH...S hydrogen bond. A relatively weak NH...S hydrogen bond in 5 can be seen in the 1H NMR spectra and the IR spectra in chloroform and in the solid state. The 199Hg NMR spectra in bis(carbamoylthiophenolato)mercury complexes 1-4 show a downfield shift, with an increase in the flow of electrons to mercury(II) from the oxygen atom due to the intramolecular Hg...O bonding interaction. Conversely, the 199Hg NMR spectra in 5 show a high-field shift with a decrease in the flow of electrons to mercury(II) from the sulfur atom due to the intramolecular NH...S hydrogen bond.     

Crystallographic study of self‐organization in the solid state including quasi‐aromatic pseudo‐ring stacking interactions in 1‐benzoyl‐3‐(3,4‐dimethoxyphenyl)thiourea and 1‐benzoyl‐3‐(2‐hydroxypropyl)thiourea

1‐Benzoylthioureas contain both carbonyl and thiocarbonyl functional groups and are of interest for their biological activity, metal coordination ability and involvement in hydrogen‐bond formation. Two novel 1‐benzoylthiourea derivatives, namely 1‐benzoyl‐3‐(3,4‐dimethoxyphenyl)thiourea, C₁₆H₁₆N₂O₃S, (I), and 1‐benzoyl‐3‐(2‐hydroxypropyl)thiourea, C₁₁H₁₄N₂O₂S, (II), have been synthesized and characterized. Compound (I) crystallizes in the space group P , while (II) crystallizes in the space group P 2₁/c . In both structures, intramolecular N—H…O hydrogen bonding is present. The resulting six‐membered pseudo‐rings are quasi‐aromatic and, in each case, interact with phenyl rings via stacking‐type interactions. C—H…O, C—H…S and C—H…π interactions are also present. In (I), there is one molecule in the asymmetric unit. Pairs of molecules are connected via two intermolecular N—H…S hydrogen bonds, forming centrosymmetric dimers. In (II), there are two symmetry‐independent molecules that differ mainly in the relative orientations of the phenyl rings with respect to the thiourea cores. Additional strong hydrogen‐bond donor and acceptor –OH groups participate in the formation of intermolecular N—H…O and O—H…S hydrogen bonds that join molecules into chains extending in the [001] direction.     

A coumarin-based fluorescent probe for Hg2+ and Ag+ with an N'-acetylthioureido group as a fluorescence switch

For detection of Hg(2+) and Ag(+), we have developed a coumarin-based probe with an N'-acetylthioureido group as a novel fluorescence switch, in which the hydrogen bond formation between the N-hydrogen and the acetyl O atom markedly increases the susceptibility of the probe toward desulfurization by Hg(2+) and Ag(+).     

Synthesis of 5-acetyl-4,6-dimethyl-1,2,3,4-tetrahydropyrimidine-2-thione and structural characterization of its polymorphs and complexes with 12-group metal iodides

A novel cyclic thiourea, 5-acetyl-4,6-dimethyl-1,2,3,4-tetrahydropyrimidine-2-thione (L), was synthesized by the reaction of N-(1-tosylethyl)thiourea with potassium enolate of acetylacetone followed by acid-catalyzed dehydration of the obtained 5-acetyl-4-hydroxy-4,6-dimethylhexahydropyrimidine-2-thione. Its polymorphs and complexes with zinc, cadmium, and mercury iodides were studied by X-ray diffraction. Two polymorphs of 5-acetyl-4,6-dimethyl-1,2,3,4-tetrahydropyrimidine-2-thione differ in ring conformation and packing manner. In the monomeric cadmium complex [CdL₂I₂], the central atom is tetrahedrally coordinated in the standard manner by iodine and thiocarbonyl S atoms, while in the dimeric mercury complex [Hg₂L₂I₄], every mercury atom is coordinated by two bridging I atoms, one terminal I atom and one thiocarbonyl S atom of the ligand. In the polymeric zinc complex [ZnLI₂], the zinc tetrahedra are linked by the bidentate bridging 5-acetyl-4,6-dimethyl-1,2,3,4-tetrahydropyrimidine-2-thione molecules through thiocarbonyl S atom and acetyl O atom.     

N-二茂铁甲酰基-N'-对乙酰基苯基硫脲的晶体及分子结构

合成的标题化合物晶体属单斜晶系, 空间群为P2~1/α, 晶胞参数为:α=0.9771(2), b=1.6752(6), c=1.1552(3)nm; β=109.23(2)°, 体积V=1.785(2)nm^3, Z=4, D~x=1.42g/cm^3, 最终偏差因子R=0.047, R~ω=0.051。结构分析表明, 在N'H-C(S)-NH-C(O)中的羰基氧和N'上的氢之间生成分子内氢键, 其为包括氢原子在内的平面六元环, 并且在二茂铁中的两个茂环平行。结合^1HNMR, IR谱矛以确证, 指出N原子上的氢应在高场(～8.0)N'上的氢原子化学位移应在低场(～12,0)。     

1-benzoyl-2-(2-naphthyl)-selenourea

During our synthesis of N-benzoyl-N'-aryl selenourea derivatives, we isolated the title compound. One of them was selected optically for the diffraction study. The crystal belongs to the Monoclinic space group P21/n, Mr = 353.27, a = 11.073(1)A, b = 5.745(1) A, c = 24.356(5) A, β= 92.10 (1) °, V= 1548.3 (4) A3, Z = 4, Dx=1.515 Mg/m3, λ (Mo Kα )=0.71073 A, θ = 1.67-25, μ= 2.428 mm-1 , T = 296 (2) K.View of the molecule showing the labeling of the non-H atoms are described as:The selenourea and thiourea have analogous structure, a few literatures have reported the crystal of N-benzoyl-N'-aryl thiourea derivative1,2. In the reported crystal structure of N-benzoyl-N'-aryl thiourea derivative, there is a intermolecular hydrogen bond between the carbonyl O and H atom on N', in each -C(O)-NH-N'H- moiety, forming a planar six-membered ring. In this title compound,[2.654(2)A], C (8), N (1) and C (7)l.In the crystal structure of N-benzoy-N'-aryl thiourea derivative, there have a two dimensional With the intramolecular hydrogen bond [2.654(2)A] they form the planar four-membered ring between every molecular. The atom of Se dose not link the moleculars like the S atom of N-benzoyl-N'-aryl thiourea derivative, and it is only out of six-membered ring, which forms by N (2)H…O, C (8), N (1) and C (7).     

Ferrocene-based novel electrochemical chemodosimeter for mercury ion recognition

A new ferrocene-based electrochemical chemodosimeter (1) for mercury(II) ion was prepared and characterized by X-ray crystal analysis. Among various metal ions, 1 displays highly selective electrochemical signaling changes for Hg²⁺ over other metal ions in regard to a mercury-promoted intramolecular cyclic guanylation of thiourea.     

A new fluorogenic chemodosimetric system for mercury ion recognition

A new probe system for fluorogenic sensing of mercury ions has been designed and synthesized. It is the first intermolecular reaction-based fluorogenic chemodosimetric probe system for Hg(II) ion recognition. High and low concentrations of mercury ions gave different fluorescence responses that could easily be distinguished by the naked eye. This unique system allows detection of the concentration and presence of the mercury ion.