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1.
为克服BODIPY类探针Stokes位移小、发射偏短等不足,本文通过在BODIPY引入α-(4-羟基)苯乙烯基增强分子内电荷转移(ICT)效应并结合meso-位Zn2+螯合团的引入构建了一个发射红移到黄色的、有较大Stokes位移(~50 nm)的BODIPY类Zn2+荧光探针。这些特点有利于降低造影中自发荧光、光毒性和激发的干扰。光谱研究显示探针具有良好的Zn2+特异性荧光增强响应,且其他金属和近中性环境pH的干扰较小。该探针对Zn2+的线性响应范围为0.12~1.2μmol·L-1,检测限为0.18μmol·L-1。HeLa细胞内Zn2+共聚焦荧光成像研究表明该探针具有良好的细胞膜透过能力,可对胞浆内"自由"Zn2+实现可逆跟踪。 相似文献
2.
以吲哚(苯并吲哚)衍生物和4-羟基苯甲醛为原料,通过一步反应合成半花菁类pH荧光探针1和2。两个探针水溶性好、发光性能稳定,它们的紫外吸收光谱和荧光光谱都能比率检测酸性和碱性溶液pH变化,探针1的两个pKa为3.81和10.01,探针2的两个pKa为4.03和10.47。两个pH探针都具有Stokes位移大、灵敏度高、可逆性好等特点。二者相比,探针1对碱性更敏感,探针2对酸性更敏感。 相似文献
3.
硫化氢在许多生理过程中扮演十分重要的角色,因此检测和成像生物体内的硫化氢具有十分重要的意义。该研究成功制备了一种基于分子内质子转移发色团的硫化氢荧光探针(DHCD)。在PBS-DMSO(磷酸盐-二甲基亚砜,99∶1,体积比,pH 7.45)缓冲溶液中,DHCD的荧光强度与NaHS的浓度在0~10μmol/L范围内呈现良好的线性关系,检出限为0.84μmol/L。该探针对硫化氢的响应具有较大的Stokes位移(~165 nm)、高灵敏度和选择性。此外,合成的探针拥有良好的细胞渗透性和低的毒性,可用于HeLa细胞中硫化氢的荧光成像,在生物分析中具有潜在应用价值。 相似文献
4.
分别以2-苯基-5-(2-吡啶基)-1,3,4-噁二唑及2,5-二苯基-1,3,4-噁二唑为荧光基团,设计合成了基于杯[4]冠醚结构的荧光探针分子1a和1b;利用核磁共振氢谱(~1H NMR)、碳谱(~(13)C NMR)及高分辨质谱(HRMS)表征了其结构.采用紫外-可见光谱及荧光光谱考察了探针分子1a和1b对碱金属离子(Na~+,K~+,Cs~+)、碱土金属离子(Mg~(2+),Ca~(2+))及过渡金属离子(Mn~(2+),Co~(2+),Ni~(2+),Cu~(2+),Zn~(2+),Cd~(2+),Ag~+)的识别作用.结果表明,Na~+可使探针分子1a的二氯甲烷溶液荧光强度显著增强,K+和Cs~+对探针分子1a的荧光强度几乎无影响,而Ca~(2+)及所有过渡金属离子均可有效猝灭探针分子1a的荧光.探针分子1b对于碱金属离子的识别作用与探针分子1a相似,但其与过渡金属离子的络合作用弱于探针分子1a.根据核磁共振表征结果讨论了金属离子与荧光探针的络合位点. 相似文献
5.
以光稳定性良好、 Stokes位移大且可近红外发射的谷胱甘肽包裹纳米金(GSH-AuNPs)为发光载体, 以4-氨基-2,2,6,6-四甲基哌啶氮氧自由基(4-NH2-TEMPO)作为顺磁标记基团, 对构建发光-顺磁双模式传感分子探针进行了研究; 以牛血清白蛋白(BSA)为表面修饰剂, 通过调节荧光纳米金的表面状态, 改善顺磁标记微环境, 获得了基于顺磁基团识别诱导信号传导的荧光-顺磁双模式响应型分子探针. 顺磁标记BSA修饰GSH-AuNPs形成弱荧光-强顺磁复合物(GSH-AuNPs@BSA-TEMPO), 复合物中顺磁基团TEMPO经抗坏血酸还原后呈现出荧光增强和顺磁信号减弱现象, 表现出对抗坏血酸浓度相关的荧光Off-on与顺磁On-off的双模式响应. 相似文献
6.
合成了一种基于苯并噻唑衍生物的荧光探针(Z)-O-(2-(苯并[d]噻唑-2-基)-4-(2-氰基-2-(4-氰基苯基)乙烯基)-6-甲基苯基)二甲基硫代氨基甲酸酯(HBTY-N),探针在Tris溶液(p H=7)中能够通过荧光“Off-On”变化,高选择性识别Cl O-.向该探针中加入ClO-后溶液由无荧光变为橙红色荧光,斯托克位移为235nm,且识别响应快速.探针HBTY-N对ClO-的检测限为2.127×10-7 mol/L, pH适用范围为1~10,并且有较强的抗干扰能力.机理研究表明,在ClO-的作用下,探针通过“氧化去保护”机制释放出具有“聚集诱导发光+激发态分子内质子转移(AIE+ESIPT)”性质的荧光团(Z)-4-(2-(3-(苯并[d]噻唑-2-基)-4-羟基-5-甲基苯基)-1-氰基乙烯基)苄腈(HBTY),量子产率由0变为42.88%.此外,探针HBTY-N可对活细胞中ClO-进行荧光成像,且对细胞毒性低,还可用于实际水样中的ClO-检测,具有潜在的应用... 相似文献
7.
水热条件下采用Zn(NO3)2.6H2O,4′-羟基-联苯-4-羧酸和1,3-二(4-吡啶基)丙烷作为反应物合成出一个新的一维锌金属配位聚合物{[Zn(Hhbc)2(bpp)].H2O}n(1)(Hhbc=4′-羟基-联苯-4-羧酸,bpp=1,3-二(4-吡啶基)丙烷),并分别用元素分析、红外光谱、差热分析、X-射线粉末衍射和X-射线单晶衍射等表征了该结构。晶体结构分析结果表明:化合物1为一维链状锌(Ⅱ)配位聚合物,通过分子间的O-H…O氢键作用,一维链进一步被连接成二维超分子结构。荧光分析表明常温固态下配合物1发射蓝色荧光,荧光寿命为3.08 ns(480 nm)。 相似文献
8.
水热条件下采用Cd(NO3)2·4(H2O),4′-羟基联苯-4-甲酸和1,3-二吡啶基丙烷作为反应物合成出一个新的一维镉配位聚合物{[Cd(4′,4-Hhbc)2(bpp)2]}n(1)(4′,4-H2hbc=4′-羟基联苯-4-甲酸,bpp=1,3-二吡啶基丙烷),并分别用元素分析、红外光谱、差热分析、X-射线粉末衍射、紫外吸收光谱和X-射线单晶衍射等表征了该结构。晶体结构分析结果表明:μ2桥联的1,3-二吡啶基丙烷将镉金属离子连接成一维链结构。荧光分析表明常温固态下配合物1发射蓝色荧光,且在440 nm处的荧光寿命为3.2 ns。 相似文献
9.
以偏苯三酸酐、4-氯间苯二酚为原料,在ZnCl2催化下反应得到2',7'-二氯-5(6)-羧基荧光素混合物,并用柱色谱进行异构体分离.对取代基团对其荧光性能影响的研究发现,顶环上引入氯使其最大荧光激发波长和荧光发射波长发生红移,荧光强度有所增加;底环上引入羧基,其Stokes位移和荧光量子产率略有降低,但该活性基团的引入将更有利于对生物体进行检测.由此表明,2',7'-二氯-5(6)-羧基荧光素有望用于荧光探针. 相似文献
10.
利用荧光发射光谱、 紫外吸收光谱和核磁共振氢谱(1H NMR)研究了八元瓜环(CB8)与2-(2-氨基-3-吡啶基)苯并咪唑(2-A3PyBI)的超分子相互作用及其对2-A3PyBI分子内质子转移过程的影响. 结果表明, 在水溶液中2-A3PyBI具有双重荧光发射峰, 分别对应其2种质子转移异构体. 固定pH值下的荧光滴定实验表明主客体包合比为1:2, 2-A3PyBI进入CB8空腔后促进了其分子内激发态质子转移过程. 同时, 1H NMR结果表明2-A3PyBI的苯环部分进入了CB8空腔. 相似文献
11.
Rajesh Bellam Surapureddy Sivamadhavi Saladi Ramakrishna Allen Mambanda Deogratius Jaganyi Nageswararao Anipindi 《Journal of Coordination Chemistry》2017,70(11):1893-1909
[Bis(3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine)(2,2′-bipyridine)iron(II)], [Fe(PDT)2(bpy)]2+ (1), [bis(3-(4-phenyl-2-pyridyl)-5,6-diphenyl-1,2,4-triazine)(2,2′-bipyridine)iron(II)], [Fe(PPDT)2(bpy)]2+ (2), [bis(2,2′-bipyridine)(3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine)iron(II)], [Fe(PDT)(bpy)2]2+ (3), and [bis(2,2′-bipyridine)(3-(4-phenyl-2-pyridyl)-5,6-diphenyl-1,2,4-triazine)iron(II)], [Fe(PPDT)(bpy)2]2+ (4) have been synthesized and characterized. Substitution of the triazine and bipyridine ligands from the complexes by nucleophiles (nu), namely 1,10-phenanthroline (phen) and 2,2′,6,2″-terpyridine (terpy) was studied in a sodium acetate-acetic acid buffer over the pH range 3–6 at 25, 35, and 45°C under pseudo-first order conditions. Reactions are first order in the concentration of complexes 1–4. The reaction rates increase with increasing [nu] and pH whereas ionic strength has no effect on the rate. Straight-line plots with positive slopes are observed when the kobs values are plotted against [nu] or 1/[H+]. The substitution reactions proceed by dissociative as well as associative paths and the latter path is predominant. Observed low Ea values and negative ΔS# values support the dominance of the associative path. Phenyl groups on the triazine ring modulate the reactivity of the complexes. The π-electron cloud on the phenyl rings stabilizes the charge on metal center by inductive donation of electrons toward the metal center, resulting in a decrease in reactivity of the complex and the order is 1 < 2 < 3 < 4. Density functional theory (DFT) calculations also support the interpretations drawn from the kinetic data. 相似文献
12.
Wan‐Ju Tai Chen‐Yu Li Pei‐Hua Lin Jia‐Ying Li Ming‐Jen Chen Bao‐Tsan Ko 《应用有机金属化学》2012,26(10):518-527
Aluminum complexes coordinated by a C1DEABTP ligand (C1DEABTP‐H = 2‐(2H‐benzotriazol‐2‐yl)‐6‐((diethylamino)methyl)‐4‐methylphenol) were synthesized and structurally characterized. The formation of Al complexes is dependent on the stoichiometry of AlMe3 to C1DEABTP ligand ratio. The reaction of C1DEABTP‐H with AlMe3 (1.0 molar equiv.) in hexane produced mono‐adduct aluminum complex [(C1DEABTP)AlMe2] (1), but treatment of C1DEABTP‐H with 2.0 molar equiv. of AlMe3 afforded mixtures of [(C1DEABTP)Al2Me5] (2) and [(C1DEABTP)Al3Me8] (3). The penta‐coordinated bis‐adduct aluminum complex [(C1DEABTP)2AlMe] (4) was synthesized through the reaction of AlMe3 with C1DEABTP‐H (2.0 molar equiv.) in hexane. Tri‐adduct Al complex [(C1DEABTP)3Al] (5) resulted from treatment of AlMe3 with C1DEABTP‐H (3.0 equiv.); the Al center is hexa‐coordinated with three N,O‐bidentate C1DEABTP ligands. X‐ray diffraction of single crystals indicates that the bonding modes of the C1DEABTP ligands in complexes 2–3 are greatly affected when excess AlMe3 is coordinated. The optical properties and catalysis for lactone polymerizations of C1DEABTP coordinated to Al complexes were tested. Tri‐adduct Al complex 5 produced an intense green fluorescence in both solution and the solid state. Complex 4 is an active catalyst for the ring‐opening polymerization of ε‐caprolactone (ε‐CL) and L‐lactide (L‐LA) in the presence of 9‐anthracenemethanol (9‐AnOH). In ε‐CL polymerization, Al complex 4 catalyzes efficiently in both a 'controlled' and 'immortal' manner, giving polymers with the expected molecular weights and narrow polydispersity indexes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
13.
《Journal of Coordination Chemistry》2012,65(9):1591-1601
Three compounds, [Zn2L2(4,4′-bpt)2] n (1), [Cd2L2(3,4′-bpt)(H2O)2] n (2) and {[CoL(3,3′-bpt)(H2O)]?H2O} n (3) (L?=?3-Cl-1,2-benzenedicarboxylate dianion, 4,4′-bpt?=?1H-3,5-bs(4-pyridyl)-1,2,4-itriazole, 3,4′-bpt?=?1H-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole and 3,3′-bpt?=?1H-3,5-bis(3-pyridyl)-1,2,4-triazole), based on three positionally isomeric triazole-bipyridine ligands, were synthesized. Structural analyses of 1–3 reveal diverse 2-D network structures, which are based on different [ML] n (M?=?Zn, Cd, Co) chains. In the [ZnL] n chains of 1, the carboxylic groups of L connect the adjacent Zn(II) centers with a monodentate bridging coordination mode (μ2-η1 ?/? η1 ). In 2, [CdL] n is a double chain connected by the carboxylic groups of L with μ3-η1 ?/? η2/η2 and μ3-η1 ?/? η1 ?/? η2 bridges. The [CoL] n chains of 3 are formed by the carboxylic groups of L with the μ2-η1 ?/? η2 coordination mode. The powder X-ray diffraction and the thermal stability of 1–3, the luminescent properties of 1 and 2, and the magnetic behavior of 3 have been briefly investigated. 相似文献
14.
《Journal of Coordination Chemistry》2012,65(4):217-224
Abstract Metal(II) perchlorate complexes with the ligands tri(2-pyridyl)phosphine, tri(2-pyridyl)phosphine oxide, and tri(2-pyridyl)arsine have the composition [M(TPX)2] (ClO4)2. Coordination occurs only through the nitrogens of the pyridines. In the case of Cu(II) and tri(2-pyridyl)phosphine oxide, two isomers were obtained. One isomer contains symmetrical tridentate tri(2-pyridyl)phosphine oxide ligands while the second isomer contains an unsymmetrical ligand. The unsymmetrical tri(2-pyridyl)phosphine oxide may be a bidentate ligand or a bridging tridentate. Weak axial interaction between a pyridyl group and a second Cu(II) ion is postulated in solution and may be present in the solid state. 相似文献
15.
无论是在水溶液还是乙腈溶液中,2-PBI(2-(2′-吡啶基)苯并咪唑)的发射光谱都表现出一定的红移,但由于该分子对Zn2+低的结合能力以及多变的配位比例,2-PBI不能作为一个比例计量型的Zn2+荧光探针。本研究通过在2-PBI的5位引入推电子基团N,N-二甲基,增加探针的配位原子数同时促进探针的ICT效应,设计合成比例计量型Zn^2+荧光探针DBITA。实验结果表明,除了172 nm的大斯托克斯位移外,DBITA还表现出特定的Zn^2+诱导的红移,发射波长从534 nm红移到609 nm,DBITA与Zn^2+以1∶1比例结合。此外,DBITA对Zn^2+表现出极高的亲和力,配合物DBITA/Zn^2+结合的Kd值为0.16 pmol·L^-1。在HeLa细胞中,DBITA完成了细胞内的Zn^2+的定量造影。 相似文献
16.
《Journal of Coordination Chemistry》2012,65(12):2022-2027
A new coordination polymer derived from Cd(II) with both rigid and flexible spacer ligands trans-1,2-bis(4-pyridyl)ethane (bpa) and 4,4′-bipyridine (4, 4′-bipy), {[Cd(μ-bpa)(4, 4′-bipy)2(H2O)2] · (ClO4)2} n has been synthesized and characterized by elemental analysis, IR-, 1H NMR spectroscopy and studied by thermal analyses as well as X-ray crystallography. The single crystal X-ray analysis shows that the complex is a 1-D polymer as a result of bridging 1,3-di(4-pyridyl)propane (bpa). The 1-D chains are further self-assembled into a 3-D network via hydrogen bonding and π–π stacking. In this structure the perchlorates fill the voids. Thermal studies of this polymer show step to step separating of ligands and counter ion at different temperatures. 相似文献
17.
由4-甲基-1,2,3-噻二唑-5-甲酸(HMTC,C4H4N2O2S)分别和1,3-双(4-吡啶基)-丙烷(bpp)、菲咯啉(phen)合成了2个锌配合物[Zn(MTC)2(bpp)]n(1)和[Zn(MTC)(phen)(H2O)2](MTC)(2)。用元素分析、红外光谱、粉末X射线衍射、热重分析对配合物进行了表征,并通过单晶X射线衍射测定了配合物的晶体结构。结果表明:配合物1是二维网状结构,属于单斜晶系,P21/c空间群,中心金属锌(Ⅱ)离子的配位构型是扭曲的四面体结构。配合物2是二维层状结构,属于三斜晶系,P1空间群,中心金属锌(Ⅱ)离子的配位构型是变形的三角双锥结构。用溴化乙锭荧光探针法测定了配体和配合物对EB-DNA复合体系相互作用,实验结果显示无论配体还是配合物均能使EB-DNA复合体系发生不同程度的荧光猝灭,且配合物的作用强度远大于配体。 相似文献
18.
Chen‐Yu Li Shi‐Jie Hsu Chin‐lung Lin Chen‐Yen Tsai Jun‐Han Wang Bao‐Tsan Ko Chia‐Her Lin Hsi‐Ya Huang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(18):3840-3849
Air‐stable copper catalysts supported by bis‐ BTP ligands ( BTP = N,O‐bidentate benzotriazole phenoxide) were synthesized and structurally characterized. The reactions of Cu(OAc)2·H2O with 2.0 molar equivalents of sterically bulky 2‐(2H‐benzotriazol‐2‐yl)‐4,6‐bis(1‐methyl‐1‐phenylethyl)phenol ( CMe2PhBTP ‐H) and 2‐(2H‐benzotriazol‐2‐yl)‐4,6‐di‐tert‐butylphenol ( t‐BuBTP ‐H) in refluxing ethanol solution afforded monomeric copper complexes [(CMe2PhBTP)2Cu] ( 1 ) and [(t‐BuBTP)2Cu] ( 2 ), respectively. The four‐coordinated copper analogue [(TMClBTP)2Cu] (3 ) resulted from treatment of 2‐tert‐butyl‐6‐(5‐chloro‐2H‐benzotriazol‐2‐yl)‐4‐methylphenol ( TMClBTP ‐H) as the ligand under the same synthetic method with ligand to metal precursor ratio of 2:1, but treatment of complex 3 in acetone gave five‐coordinated monomeric complex [(TMClBTP)2Cu(Me2CO)] (4 ). X‐ray diffraction of single crystals indicates that Cu complex 4 assumes a distorted square pyramidal geometry, penta‐coordinated by two BTP ligands, and one Me2CO molecule. Catalysis for lactide (LA) polymerization of BTP ‐containing Cu complexes in the presence of various alcohol initiators was investigated. Complex 3 initiated by 9‐anthracenemethanol catalyzes the ring‐opening polymerization effectively not only in a “living” fashion but also in an “immortal” manner, yielding polymers with the predictable molecular weights and narrow molecular weight distributions. Initiations from multifunctional alcohols were able to produce PLLAs with two‐arm linear and three‐arm star‐shaped molecular architectures. The controlled character of Cu complex 3 also enabled us to synthesize the PEG‐b‐PLLA copolymer. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3840–3849 相似文献
19.
《Journal of Coordination Chemistry》2012,65(23):4066-4078
Three pyridylbenzimidazoles (2-PBIM, 3-PBIM, and 4-PBIM) have been prepared (2-PBIM: 2-(2-pyridyl)-benzimidazole, 3-PBIM: 2-(3-pyridyl)-benzimidazole, 4-PBIM: 2-(4-pyridyl)-benzimidazole). Reactions of several transition metals (Cd2+, Cu2+, Fe2+) with the three ligands gave four new coordination complexes, [(Cd)2(2-PBIM)2(CH3COO)4] (1), [Cu(3-PBIM)2(CH3COO)2]?·?2H2O (2), [Cu(4-PBIM)2(CH3COO)2(H2O)]?·?H2O (3), and [Fe(4-PBIM)2(Cl)2(H2O)2] (4), respectively. These four complexes have been characterized by X-ray crystallography, IR spectroscopy, and UV absorption spectroscopy. Thermogravimetric properties of 2 and 4 were also measured. X-ray crystallographic studies reveal that these four complexes are very different, although the ligands are similar in structure. The role of hydrogen-bonding and π–π interactions in extending dimensionality of simple complexes has been discussed. 相似文献
20.
《Journal of Coordination Chemistry》2012,65(24):4375-4388
Four new fpa-metal complexes, [Co(fpa)2(H2O)2] (1), [Cu(fpa)2(H2O)] (2), [Zn2(fpa)4(bpp)2] n (3), and {[Zn(bpy)(H2O)4]?·?2(fpa)} n (4), have been synthesized and fully characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction, and thermogravimetric analysis (TGA), (Hfpa?=?2,2-difluoro-2-(pyridine-2-yl)acetate, bpp?=?1,3-bis(4-pyridyl)propane, bpy?=?4,4′-bipyridine). X-ray diffraction analyses reveal that 1 and 2 with 0-D structures are both extended into 3-D supramolecular networks through hydrogen bonds and π···π interactions. Complex 3 with chiral centers possesses a 1-D structure constructed by two kinds of bpp molecules and four kinds of fpa? molecules with different conformations, with bbp and fpa? bridging and capped ligands, respectively. In 4, bpy links [Zn(H2O)4]2+ into a 1-D polymeric cationic chain and uncoordinated fpa? compensates the framework charge. The results of TGA reveal that fpa? decomposes through two processes. Both 3 and 4 show strong fluorescence in the solid state at room temperature. 相似文献