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1.
两性金属卟啉衍生物的合成   总被引:4,自引:0,他引:4  
气体传感器的传感介质的研究目前大多集中在具有共轭大。键的外琳和酞青这两类有机化合物上[’·’].金属叶琳具有载气功能,血红素便是其中一例.这种配合于叶琳环上的金属离子与气体的可逆配位作用,使该化合物在与气体配位前后发生光电性能变化而具有气体传感特性.我们设计将金属叶琳LiLangmuir-Blodgett(L)膜技术组装到具有光波导结构的器件上.为了满足LB膜技术对分子结构的要求,使有机分子在气一液界面能形成较好的单分子层膜,必需对叶琳进行化学修饰,引人长链烷氧基疏水基团和羟基亲水基因.另外,有机分子对气体的选择…  相似文献   

2.
单链四苯酚基卟啉在CTAB胶束微环境中的去质子化现象   总被引:4,自引:1,他引:4  
叶绿素分子的光能转化功能的实现与其聚集状态、所处微环境性质及条件密切相关[1,2].如何设计控制叶琳类分子在膜介质中的增溶位置,对于研究叶琳在膜体系中的跨膜电子传递、光能转化过程具有重要意义.本文研究了长链双亲卟啉──单链四苯酚基叶琳THPPH2在CTAB胶束中的去质子化,该过程能控制叶琳环在胶束中的增溶位置,使其由内核转移到胶束表面.1实验部分1·1仪器和测试条件岛津UV-240型紫外可见光谱仪(带有恒温夹套),狭缝宽2nm,石英池厚1cm,所用试剂皆为分析纯.UV光谱测试均在恒温条件下进行.1.2溶液的配制含一个十六…  相似文献   

3.
含长链烷基的单羧基卟啉的合成及LB膜特性   总被引:4,自引:0,他引:4  
近年来,国际上对有机光电子材料的研制和开发已成为热门课题。具有优良光电特性的卟啉分子的合成及其LB膜的结构和特性的研究,已引起人们的重视。本工作设计和合成了一种新型的含长链烷基的单羧基双亲性卟啉(Ⅳ),其结构见下图,它能在水面上展开成稳定的单层膜,并且进一步研究了这种超薄膜的结构和性质。  相似文献   

4.
根据四甲基吡啶铜叶啉(CuTMPyP)的光谱电化学和部分质子化的5,10,15-三(4-羟基苯基)-20-(4-十六烷氧苯基)卟啉(P31)LB膜的荧光光谱,研究了卟琳衍生物离子自由基二聚体的电子光谱.电还原产生的CuTMPyP负离子自由基与基态分子通过SOMO’-LUMO作用形成面对面二聚体,在480nm处出现二聚体的Q带,在820nm处出现π*→π*带.质子化产生的P31正离子自由基与基态分子通过SOMO-HOMO作用形成面对面二聚体,在470~515nm处出现二聚体的Q带吸收,在710nm出现π→π带.与单体Q带相比这些Q带发生蓝移.  相似文献   

5.
用LB膜技术将含有长侧碳链的泛醌或质体醌类似物转移到导电玻璃上,用循环伏安法研究了它们的电化学行为.发现醌环上的取代基对其电化学行为有明显影响,提出了泛醌类似物和质体醌类似物在LB膜上的具体电化学过程.  相似文献   

6.
研究了两亲性卟啉5,10,15,20-四-(4-N,N,N-二甲基十六烷基氨基苯基)卟啉(TDMC16PP)在气/液界面上的成膜性能,制备了其多层LB膜。用UV-Vis吸收光谱、荧光光谱、偏振UV-Vis吸收光谱和小角X射线衍射对LB膜进行了测试表征。结果表明:两亲性卟啉TDMC16PP具有良好的成膜性能,其LB膜性质稳定,有较好的结构均匀性和周期性。在LB膜内,脂肪链并不是直立的,卟啉大环平面与基片平面成42.5°排列。  相似文献   

7.
聚丙交酯(PLA)可以生物降解,产物无毒,可用于外科手术的缝合线、人造器官以及药物缓释等方面,因此引起了人们的广泛注意.丙交酯的开环聚合是合成聚丙交酯的一种方便方法,所用的催化剂主要是主族及副族金属的配合物,如双金属氧桥配合物[‘j,烷基金属有机化合物[‘j,异丙氧基铝[’‘以及叶琳铝「“等.最近,关于三价烷氧基稀土化合物作为单组份催化剂催化丙交酯开环聚会已有报道[’·’‘.我们发现两价芳氧基稀土化合物(ArO)。Sin(THF)。(ArO一2,已二叔丁基一个甲基苯氧基)也可以有效地催化丙文酯的开环聚合.本…  相似文献   

8.
铜卟啉,钒氧卟啉的合成   总被引:1,自引:0,他引:1  
王煜  何明威 《应用化学》1996,13(6):67-68
铜卟啉、钒氧卟啉的合成王煜,何明威,王军强,武靖荣(山西大学化学系太原030006)关键词卟啉,铜卟啉,钒氧卟啉,合成合成金属卟啉,通常是先合成卟啉,再将卟啉与金属盐反应,经柱色谱分离后得到目标化合物[1].本文报道以酚为溶剂,使吡咯、芳香醛和乙酸铜...  相似文献   

9.
荧光素衍生物LB膜对TiO2电极的光敏化作用   总被引:19,自引:0,他引:19  
合成了三种荧光素长碳链衍生物,通过LB技术将它们组装成单分子薄膜,修饰在用溶胶-凝胶法制备的TiO2透明电极上,研究了这些LB膜的结构和特性及它对TiO2的光增感作用.并对其光敏化机理作了阐述.  相似文献   

10.
在卟啉的苯环上接上4~30个碳的长链,则其光电化学性能增强,并成为性能良好的充电导膜材料及照相感光材料。为此,本文合成了5-(p-十六烷氧基苯基)-10,15,20-三苯基卟啉(Ⅱ)和5-(p-十六羰酰氧苯基)-10,15,20-三苯基卟啉(Ⅲ),合成路线如下:  相似文献   

11.
长碳链季铵类卟啉钴配合物的合成及其LB膜和气敏性质   总被引:4,自引:0,他引:4  
四-(4-N,N,N-二甲基)卟啉(TDMAPP)与溴代正十六烷反应得到溴化四-(4-N,N,N-二甲基,十六烷基氨基苯)卟啉(TDMHAPPBr)并制得其钴的配合物,两者均具有良好的成膜性。电子吸收光谱表明LB膜与成膜前固体物分子排列规整性不同,钴配合物对敢有较好的敏感性和良好的选择性,其响应和恢复时间都较短。  相似文献   

12.
Three novel porphyrins, including two Schiff‐bases porphyrins, 5,10,15‐triphenyl‐20‐[4‐(2‐(4‐formyl)phenoxy)ethoxy]phenyl porphyrin ( H2Pp ( 1 )), 5,10,15‐triphenyl‐20‐[4‐(2‐(4‐hydroxyimino)phenoxy)ethoxy]phenyl porphyrin ( H2Pp ( 2 )) and 5,10,15‐triphenyl‐20‐[4‐(2‐(4‐m‐hydroxyanilinodeneformyl)phenoxy)ethoxy]phenyl porphyrin ( H2Pp ( 3 )), as well as three metalloporphyrins ( CuPp ( 1a ), ZnPp ( 1b ), and CoPp ( 1c )) of porphyrin H2Pp ( 1 ) were synthesized. Their molecular structures were characterized by 1H‐NMR, MS, UV/VIS, and FT‐IR spectra. Furthermore, they were evaluated by their cytotoxicities against human epidermal squamous cell carcinoma cell (A431) and normal human horn cells (HaCaT) in vitro with MTT assay. Interestingly, these porphyrins and metalloporphyrins, which had a negligible cytotoxicity to HaCaT cells, showed highly cytotoxicity against A431 cells with IC50 values in the range of 6.6–9.8 μM , and metalloporphyrins exhibited higher cytotoxicity than that of metal‐free porphyrins.  相似文献   

13.
The aim of this work is to synthesize of a new family of lactosylated piperazinly porphyrins, in which the galactoside piperazine moieties are linked to the tetra‐ and mono‐phenyl rings of tetraphenylporphyrin (TPP). 5,10,15,20‐Tetrakis[4‐(4‐lactobionylpiperazin‐1‐yl)phenyl]porphyrin (TLPP) and 5‐mono[4‐(4‐lactobionylpiperazin‐1‐yl)phenyl]‐10,15,20‐triphenylporphyrin (MLPP) have been synthesized. A detailed 1H NMR study gave their complete structural elucidation. The UV‐Visible, mass spectra and elemental analysis are also presented. The biological activity on cancer cells and the pharmacokinetics have also been evaluated, showing a better biological activity, a very high liver to skin ratio and short retention time in tissues. It was suggested that such novel lactosylated piperazinly porphyrins, as potential hepatocyte‐selective targeting drugs, exhibit a promising activity in photodynamic therapy (PDT).  相似文献   

14.
Three disubstituted N-confused porphyrins (2-4) were prepared in ca. 4% yield using a one-pot synthesis. These porphyrins bear 3,5-di-tert-butylphenyl groups substituted at the C(5) and C(20) meso positions and para-substituted (Br, NO(2), ethynyl) phenyl groups at the C(10) and C(15) meso positions. The specific orientation of the aryl rings around the macrocycle in porphyrin 2 was definitively determined using a combination of 1D ((1)H and (13)C) and 2D (gHMQC and gHMBC) NMR spectroscopy. The absorption spectra of 2-4 in CH(2)Cl(2) and dimethylacetamide are similar to those of N-confused tetraphenylporphyrin in the same solvents but have Soret and Q-bands that are shifted to lower energies. Steady-state fluorescence measurements revealed Q(x)(0,0) and Q(x)(0,1) bands similar in energy to the unsubstituted NCPs 1i and 1e. The fluorescence quantum yield results for two of these NCPs (2, 4) are atypical of porphyrin behavior and are being further investigated by time-resolved spectroscopy.  相似文献   

15.
The photophysical properties for a series of free-base arylethynyl porphyrins and the corresponding trans-disubstituted tetraphenylporphyrin (H(2)TPP) derivatives lacking arylethynyl functionalities have been studied via electronic absorption and emission spectroscopy in both neutral and diacid forms. Enhanced substituent effects on porphyrin absorption spectra are observed in the arylethynyl porphyrins relative to the H(2)TPP derivatives, owing to the presence of the ethynyl spacer that allows for a coplanar geometry between the porphyrin macrocycle and the appended phenyl substituents. Upon protonation, both series of porphyrins exhibit substantially red shifted absorption and emission spectra and enhanced oscillator strengths, with the magnitude of the spectral shifts being more substantial in the presence of the ethynyl functionalities. Spectral features of the arylethynyl porphyrin bearing p-dimethylamino substituents closely resemble those previously classified as "hyperporphyrin spectra" and are indicative of excited-state charge-transfer character. Protonation of both series of porphyrins results in reduced fluorescence lifetimes and enhanced nonradiative decay rates, and the impact of protonation on these parameters is attenuated in the presence of the arylethynyl functionalities. Our results coupled with previous structural data showing that arylethynyl porphyrins exhibit less structural distortion upon diacid formation relative to H(2)TPP further substantiate the proposal that significant alteration of porphyrin photophysical properties upon diacid formation can be attributed to nonplanar structural distortions induced by protonation.  相似文献   

16.
Interactions of multivalent anionic porphyrins and their iron(III) complexes with cationic peptides, V3Ba‐L and V3IIIB, which correspond to those of the V3 loop regions of the gp120 envelope proteins of the HIV‐1Ba‐L and HIV‐1IIIB strains, respectively, are studied by UV/Vis, circular dichroism, 1H NMR, and EPR spectroscopy, a microcalorimetric titration method, and anti‐HIV assays. Tetrakis(3,5‐dicarboxylatophenyl)porphyrin (P1), tetrakis[4‐(3,5‐dicarboxylatophenylmethoxy)phenyl]porphyrin (P2), and their ferric complexes (FeIIIP1 and FeIIIP2) were used as the multivalent anionic porphyrins. P1 and FeIIIP1 formed stable complexes with both V3 peptides (binding constant K>106 M ?1) through combined electrostatic and van der Waals interactions. Coordination of the His residues in V3Ba‐L to the iron center of FeIIIP1 also played an important role in the complex stabilization. As P2 and FeIIIP2 form self‐aggregates in aqueous solution even at low concentrations, detailed analysis of their interactions with the V3 peptides could not be performed. To ascertain whether the results obtained in the model system are applicable to a real biological system, anti‐HIV‐1BA‐L and HIV‐1IIIB activity of the porphyrins is examined by multiple nuclear activation of a galactosidase indicator (MAGI) and 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assays. There is little correlation between chemical analysis and actual anti‐HIV activity, and the size rather than the number of the anionic groups of the porphyrin is important for anti‐HIV activity. All the porphyrins show high selectivity, low cytotoxicity, and high viral activity. FeIIIP1 and FeIIIP2 are used for the pharmacokinetic study. Half‐lives of these iron porphyrins in serum of male Wistar rats are around 4 to 6 h owing to strong interaction of these porphyrins with serum albumin.  相似文献   

17.
The carbonylation of phenyl bromide catalyzed by Co(OAc)2 has been investigated with PhCOPh as a sensitizer under visible light in the presence of basic additive.With strong base CH3ONa,PhCOOCH3 is produced in 70%yield with 100%selectivity,the similar results are also obtained with a stronger base(CH33CONa.However,with another strong base NaOH,the yield of the ester is only 40%.On the other hand,with weak base NaOAc or(n-C4H93N,phenyl bromide cannot be carbonylated.The results of carbonylation of the six substituted phenyl bromides suggest that the activities of o,m,p-BrC6H4CH3 are similar to phenyl bromide, while the activities of o,m,p-BrC6H4Cl are higher with the high yields(≥93%) of the corresponding chloro-esters.In addition,the relative position of bromine and chlorine or methyl on phenyl ring has little effect on the activity of the carbonylation.  相似文献   

18.
meso-四(烷氧基苯基)卟啉及其金属络合物的波谱研究   总被引:2,自引:0,他引:2  
采用^1H NMR、MS、IR、UV、元素分析等分析测试表征手段确证了所合成的10个系列卟啉及其金属络合物的结构,研究了不同位置、不同链长烷氧基四苯基卟啉和不同金属离子卟啉络合物的结构与^1HNMR、IR和UV等波谱之间的关系,总结了卟啉配体及其金属络合物的^1H NMR、IR和UV判据,报道和解释了meso-四(烷氧基苯基)卟啉铜、锰络合物和meso-四(邻烷氧基苯基)卟啉钴络合物的^1H NMR研究结果,通过MS、^1H NMR、IR、UV、元素分析确证了我们所合成的铁卟啉为μ-氧桥联夹心二聚体结构,且存在两种典型构象,导致同系列络合物有四种类型^1H NMR谱图。  相似文献   

19.
Study on the interaction of new water-soluble porphyrin with DNA   总被引:1,自引:0,他引:1  
A porphyrin meso-tetrakis{[4-(1-pyridyl)propoxy]phenyl}porphyrin (TPyPP) and its Ni complex (TPyPP(Ni)) have been synthesized and characterized by 1H NMR, UV-vis spectra. The interaction of two porphyrins with calf thymus-DNA (CT-DNA) has been explored by UV-vis, fluorescence and circular dichroic spectroscopy and viscosity measurements. The results suggest that these porphyrins can bind to DNA by the same binding mode. TPyPP outside binds by self-stack with DNA both at low drug load r (=[porphyrin]/[DNA]) and high drug load. Though TPyPP(Ni) has center metal nickel, binding mode with DNA has little difference compared with TPyPP, dominating out-binding mode with different direction along DNA. The binding constants of the TPyPP and TPyPP(Ni) to DNA were 4.65 x 10(5) M(-1) and 3.2 x 10(5) M(-1), respectively. A colored precipitate was found after time in two porphyrin's viscosity measurement. The reasonable interpretation is the porphyrins with alkyl connected N-position of pyridine can strongly interact with the anionic phosphates of DNA and lead to hydrophobic complex.  相似文献   

20.
To examine the influence of mixed substituents on the structural, electrochemical redox behavior of porphyrins, two new classes of beta-pyrrole mixed substituted free-base tetraphenylporphyrins H2(TPP(Ph)4X4) (X = CH3, H, Br, Cl, CN) and H2(TPP(CH3)4X4) (X = H, Ph, Br, CN) and their metal (M = Ni(II), Cu(II), and Zn(II)) complexes have been synthesized effectively using the modified Suzuki cross-coupling reactions. Optical absorption spectra of these porphyrins showed significant red-shift with the variation of X in H2(TPPR4X4), and they induce a 20-30 nm shift in the B band and a 25-100 nm shift in the longest wavelength band [Q(x)(0,0)] relative to the corresponding H2TPPR4 (R = CH3, Ph) derivatives. Crystal structure of a highly sterically crowded Cu(TPP(Ph)4(CH3)4).2CHCl3 complex shows a combination of ruffling and saddling of the porphyrin core while the Zn(TPP(Ph)4Br4(CH3OH)).CH3OH structure exhibits predominantly saddling of the macrocycle. Further, the six-coordinated Ni(TPP(Ph)4(CN)4(Py)2).2(Py) structure shows nearly planar geometry of the porphyrin ring with the expansion of the core. Electrochemical redox behavior of the MTPPR4X4 compounds exhibit dramatic cathodic shift in first ring oxidation potentials (300-500 mV) while the reduction potentials are marginally cathodic in contrast to their corresponding MTPPX4 (X = Br, CN) derivatives. The redox potentials were analyzed using Hammett plots, and the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap decreases with an increase in the Hammett parameter of the substituents. Electronic absorption spectral bands of H2TPPR4X4 are unique that their energy lies intermediate to their corresponding data for the H2(TPPX8) (X = CH3, Ph, Br, Cl) derivatives. The dramatic variation in redox potentials and large red-shift in the absorption bands in mixed substituted porphyrins have been explained on the basis of the nonplanarity of the macrocycle and substituent effects.  相似文献   

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