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1.
Metalloporphyrin arrays covalently and noncovalently linked, together with their syntheses and properties, are reviewed.  相似文献   

2.
Crystal-engineering strategies have been systematically developed for the rational design by self-assembly of diverse metalloporphyrin molecular-sieve materials. Cooperative coordination and hydrogen bonding algorithms of molecular recognition proved particularly useful for this aim. The supramolecular concepts used in the construction of stable nanoporous solids and some unique sieve-type structures obtained thus far are illustrated.  相似文献   

3.
The review summarizes data on the reversible addition of inorganic and organic biologically active bases at the coordination sites of mixed complexes containing the porphyrin dianion as one of ligands. An analysis of the thermodynamic parameters revealed new receptors for small cyclic molecules holding promise for analytical purposes and sensorics. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 636–654, April, 2007.  相似文献   

4.
Ocular phototoxicity.   总被引:2,自引:0,他引:2  
The human eye is constantly exposed to sunlight and artificial lighting. Therefore the eye is exposed to UV-B (295-320 nm), UV-A (320-400 nm), and visible light (400-700 nm). Light is transmitted through the eye and then signals the brain directing both sight and circadian rhythm. Therefore light absorbed by the eye must be benign. Damage to the young and adult eye by intense ambient light is avoided because the eye is protected by a very efficient antioxidant system. In addition, there are protective pigments such as the kynurenines, located in the human lens, and melanin, in the uvea and retina, which absorb ambient radiation and dissipate its energy without causing damage. After middle age there is a decrease in the production of antioxidants and antioxidant enzymes. At the same time, the protective pigments are chemically modified (lenticular 3-hydroxy kynurenine pigment is enzymatically converted into the phototoxic chromophore xanthurenic acid; melanin is altered from an antioxidant to pro-oxidant) and fluorescent chromophores (lipofuscin) accumulate to concentrations high enough to produce reactive oxygen species. We have known for some time that exposure to intense artificial light and sunlight either causes or exacerbates age-related ocular diseases. We now know many of the reasons for these effects, and with this knowledge methods are being developed to interfere with these damaging processes.  相似文献   

5.
卟啉及金属卟啉的应用   总被引:11,自引:0,他引:11  
卟啉和金属卟啉类化合物在仿生化学、催化、太阳能利用、特种材料、医学和分析化学等方面有着越来越重要的作用和应用。本文作一简单介绍。  相似文献   

6.
Rigid and flexible linkers are combined in the new dendrimer shown schematically in the picture, which contains nine metalloporphyrin units (Porph). The construction is such that the four “arms” of the dendrimer can fold in a cooperative and predetermined manner in response to added 1,4-diazabicyclo[2.2.2]octane (DABCO).  相似文献   

7.
A series of bis-acryl functionalized porphyrins and their corresponding metalloporphyrins (M=Co, Mn) were synthesized and investigated for their antimicrobial properties through MIC screening and bacteria time-kill kinetic studies. The Mn(III) 4-(bis)methylphenyl-substituted-porphyrins showed superior batericidal activities even in the dark with low hemotoxicity and good cytotoxicity profile.  相似文献   

8.
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   

9.
The formation of specific molecular complexes of synthetic and natural porphyrins and metalloporphyrins with molecular ligands of different nature is considered. Data on composition, energy and thermal stability of donor–acceptor and –-complexes of porphyrins and metalloporphyrins were obtained by thermogravimetric analysis of crystal solvates.  相似文献   

10.
Two new ditopic metalloporphyrin receptors constructed by combining metalloporphyrin with crown ethers have been prepared and characterized.1H NMR and MS spectra confirmed the complexation of receptor with peptide driven by coordination interaction and hydrogen bonding.UV/vis experiments revealed that the receptors exhibited high binding affinity to histidine-containing peptides.These receptors could differentiate short peptides of C-terminal histidine and N-terminal histidine and formed the most stable complexes with tripeptide.  相似文献   

11.
12.
TheSynthesisofStarStyleMetaloporphyrinTONGShan-ling(ChangchunLightIndustrySchool,Changchun,130021)YANYan**LIZhi-hai,GUOKuia,Z...  相似文献   

13.
金属卟啉作为过氧化物模拟酶在分析化学中的应用   总被引:6,自引:0,他引:6  
贴建科  常文保 《分析化学》1994,22(5):516-522
本文结合本实验室的研究工作,对金属卟啉作为过氧化物模拟酶在光度分析,荧光分析和化学发光分析中的应用进行了较为系统的评述,涉及参考文献48篇。  相似文献   

14.
15.
不同金属四苯基卟啉(TPPM)催化氧化苯甲醛时,TPPMnOAc催化活性最高,TPPFeCl次之,TPPCo和TPPNi几乎无活性;TPPMnOAc苯环上吸电子取代基的存在有利于提高其催化活性和稳定性,苯环上邻位吸电子取代基能明显提高四苯基锰卟啉的稳定性,但由于空间位阻的原因,使其催化活性降低.在本模拟体系中,T(2,6 di Cl)PPMnOAc是一个较理想的催化剂.  相似文献   

16.
本文综述了近几年来手性金属卟啉配合物在主客体化学、立体催化及光电化学领域的性能研究成果。分析了在主客体化学中手性卟啉作为分子识别反应主体所具有的结构特征;介绍了模拟生物大分子的功能时手性卟啉所反映出的识别机制;评述了手性卟啉对苯乙烯及其衍生物的环丙烷化、羟基化及氨化等催化反应中所展示出的对映选择性和催化稳定性;概括了手性卟啉配合物在模拟植物光合成反应和制作新型光学材料方面所具有的光电性能。最后总结了手性卟啉研究成果的应用范围,并展望了手性卟啉在催化氧化方面的研究和发展方向。  相似文献   

17.
磁光学活性与自然光学活性均可用介质对左右圆偏振光的吸收之差来表示 .但自然光学活性和磁光学活性的物理机制是截然不同的 ,前者源于镜象不能互相重叠介质的非定域光学响应 ( nonlocaloptical response) ,而后者则是由于介质的时间反演对称性 ( time- reversal symmetry)被磁场打破所致 .理论分析表明 ,当介质的两种光学活性同时存在时 ,将会出现一个新的附加光学效应 ,这种磁光学活性与自然光学活性之间的交叉效应称为磁手性效应 ( magneto- chiral effect)或磁手二色性 ( magneto-chiral dichroism) [1,2 ] .磁手性效应通常很弱 ,直到 1…  相似文献   

18.
在生命活动中起重要作用的蛋白质和金属卟啉是典型的生物高分子和金属配合物,而且绝大部分蛋白质与金属卟啉是通过形成结合体共同发生作用的,因此,研究天然金属卟啉蛋白质结合体的结构与功能并进行人工模拟受到关注并取得了很大进展。本文在对蛋白质与金属卟啉的结构与类型进行简单介绍的基础上,综述了 金属卟啉与蛋白质的天然结合体,如细胞色素P-450、过氧化物酶、血红蛋白、肌红蛋白及脑红蛋白等。总结了金属卟啉与蛋白的人工结合体,如原卟啉、血卟啉及其衍生物与血清白蛋白的结合体;合成水溶性与不溶性金属卟啉与白蛋白的结合体。介绍了人工合成蛋白,即基因重组蛋白与合成金属卟啉的结合体,如用做人工合成血液的栏式铁卟啉白蛋白结合体。到目前为止,不但金属卟啉可以合成,而且白蛋白、血红蛋白也可以通过基因重组进行人工合成。金属卟啉蛋白质结合体已应用于制备人工血液、疾病检测、治疗,及光解水产氢等多个领域。  相似文献   

19.
高分子键联金属卟啉的合成及催化性能;高分子担载金属卟啉; 环己烯; 催化氧化  相似文献   

20.
The photochemical properties and degradation of the common nonsteroid anti-inflammatory drug ibuprofen is studied by means of hybrid density functional theory. Computed energies and properties of various species show that the deprotonated form dominates at physiological pH, and that the species will not be able to decarboxylate from a singlet excited state. Instead, decarboxylation will occur, with very high efficiency, provided the deprotonated compound can undergo intersystem crossing from an excited singlet to its excited triplet state. In the triplet state, the C-C bond connecting the carboxyl group is elongated, and the CO2 moiety detaches with a free energy barrier of less than 0.5 kcal/mol. Depending on the local environment, the decarboxylated product can then either be quenched through intersystem crossing (involving the possible formation of singlet oxygen) and protonation, or serve as an efficient source for superoxide anions and the formation of a peroxyl radical that will initiate lipid peroxidation.  相似文献   

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