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1.
Abstract— Sulfonated phthalocyanine and a series of its metal chelates in combination with red light irradiation led to the degradation of L-tryptophan in oxygenated aqueous solution. The photoproducts and the rate of transformation of L-tryptophan are compared with hematoporphyrin and rose bengal sensitized photooxidation. In all cases the primary photoproducts are characterized as cis and trans -3a-hydroperoxy-l,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-2-carboxylic acid. Support for the involvement of singlet excited oxygen is obtained from azide inhibition and the formation of the specific singlet oxygen product with cholesterol. We observed the contribution of another pathway in the case of the manganese complex.  相似文献   

2.
Abstract— Water soluble chloro aluminum phthalocyanines sulfonated to different degrees are studied for phototoxicity and cellular distribution inV–79 Chinese hamster cells. The more hydrophobic disulfonated dyes, with sulfonate substituents on adjacent benzyl groups of the phthalocyanine ring structure, exhibited the best cell penetrating properties and the highest phototoxicity. Fluorescence microscopy revealed that the dye was uniformly distributed in the cytoplasm but absent in the nucleus. The greater cell membrane penetrating properties of the lower as compared to the higher sulfonated dyes are attributed to the amphiphilic nature of the former.  相似文献   

3.
Abstract Gallium chloride phthalocyanines sulfonated to different degrees were tested for their ability to inactivate V-79 Chinese hamster cells in the presence of red light. The mono- and disulfonated compounds were the most active whereas the tri- and tetrasulfonated complexes were completely void of photoactivity. In addition, large variations in photoactivity were observed among the four isomeric disulfonated derivatives with the most hydrophobic isomer exhibiting the highest photoactivity. Prolonged exposure to the disulfonated complex resulted in increased photosensitization. Complexing the dye with Al instead of Ga resulted in a slightly increased photosensitizing effect.  相似文献   

4.
Abstract— The photosensitized oxidation of L-tryptophan by gallium phthalocyanines sulfonated to different degrees is studied as a function of both substrate and sensitizer concentrations in water and 50% MeOH-H2O solutions. The maximum quantum yield of singlet oxygen was found to be nearly 0.5 for all sulfonated gallium complexes. The effect of adding sulfonate groups in the phthalocyanine backbone is to change the tendency of dye molecules to dimerize or aggregate in a particular solvent. A shift in the chemical equilibrium away from the monomeric state, which occurs at high dye concentrations and at lower degrees of dye sulfonation, results in a reduced photochemical yield. The variation of quantum yields in different solvent systems and at several wavelengths is similarly accounted for by the fraction of light absorbed by the productive monomer state.  相似文献   

5.
Abstract— Zinc phthalocyanines sulfonated to different degrees are tested for their ability to sensitizeV–79 Chinese hamster cells andEMT–6 mouse mammary tumors to red light. In vitro , the lower sulfonated derivatives were the most active with the exception of the poorly water-soluble monosulfonated dye. An isomeric mixture of tetrasulfonated derivatives obtained via direct sulfonation was ten times more active than the homogeneous tetrasulfo derivative prepared via the condensation of sulfophthalic acid. In vivo , the latter dye was completely inactive, whereas the remainder of the sulfonated preparations exhibited a similar structure-activity pattern as observed with theV–79 cells in vitro . The disulfonated zinc phthalocyanine showed the best tumoricidal activity in the series and also appeared to be a more efficient photosensitizer of cell inactivation and tumor cure than the aluminum or gallium complexes as well as hematoporphyrin derivative preparations. No significant differences in skin phototoxicity were observed among the various dyes.  相似文献   

6.
四苯(基)苯基多乙烯基硅油的合成及结构测定   总被引:3,自引:0,他引:3  
<正> 多乙烯基硅油是高温硫化硅橡胶的集中交联剂,当无耐热填料时,所得硫化胶的耐热性不高。为了使多乙烯基硅油既具有集中交联作用,又赋予耐热性,本文采用Diels-AIder反应合成了含有四苯(基)苯基的多乙烯基硅油。前文曾合成多种多苯(基)苯基有机硅化合物,但实验在封管内进行,诸多不便,投量也甚少,为此,改用高沸点溶剂(α-氯萘),在常压下反应,得到了高产率的四苯(基)苯基多乙烯基硅油:  相似文献   

7.
用吸收光谱和荧光光谱研究了不同磺化程度酞菁与不同胶束间的相互作用并计算了结合常数。低磺化程度酞菁与三类胶束间均可发生相互作用,其标志是胶束的解聚作用;而高磺化程度酞菁与此显著不同,可结合在阳离子胶束表面,与非离子胶束无明显作用,而阴离子胶束对磺化酞菁只起促聚作用。用磺化程度变化导致酞菁分子体积、电荷及疏水性变化解释了实验结果。  相似文献   

8.
嘧啶脲类化合物的合成及其除草活性   总被引:6,自引:0,他引:6  
嘧啶脲类化合物的合成及其除草活性李斌林柄栋刘长令魏晓丽(化工部沈阳化工研究院沈阳110021)关键词嘧啶异氰酸酯嘧啶脲合成除草剂40年代开发的取代脲除草剂如敌草隆等已得到了广泛应用[1],但由于用药量较大,已逐渐被磺酰脲类除草剂取代。在这类磺酰脲除草...  相似文献   

9.
许多乙酰芳胺类化合物具有优异的生物活性,例如除草剂苯噻草胺,可抑制细胞生长和分裂,防除稻田中禾本科杂草[1];杀菌剂甲霜灵可防治作物霜霉病[2]。本文将具有多种生物活性的嘧啶基团引入到乙酰芳胺结构中[3],合成下列10个未见文献报道的标题化合物Ⅰ,通...  相似文献   

10.
In this article, we incorporated the organic phosphorus group on to a triazolothiadiazole ring to prepare the title compounds fused 1,2,4-triazolo[3,4-b][1,3,4]thiadiazole heterocyclic compounds. From the results on biological activities, we found that most compounds showed weak activities, and thus the structures need to be further optimized for improved activity.  相似文献   

11.
Abstract— The effect of human serum components on the photodynamic activity of zinc phthalocyanine (ZnPc) toward Chinese hamster fibroblasts (lineV–79) was studied. Photodynamic activities were correlated with cellular uptake of radiolabeled [65Zn]ZnPc, which allowed corrections to be made for the amount of sensitizer present in the cells at the time of irradiation and to express photodynamic efficiences on a cellular dye concentration basis. All serum components, with the exception of high-density lipoproteins, inhibit uptake of ZnPc byV–79 cells, when compared to incubation of ZnPc with the same cells in serum-free medium. High-density lipoproteins increased ZnPc uptake by 23%, but the photodynamic efficiency corrected for the cellular ZnPc concentration was unaffected. Very low-density lipoprotein and globulins decreased ZnPc cell uptake but likewise did not affect the cellular photodynamic efficiency of the dye. In contrast low-density lipoprotein and albumin, while inhibiting ZnPc cell uptake, increased the cellular photodynamic efficiency of ZnPc, suggesting that these proteins facilitate localization of the dye at cellular targers sensitive to photodynamic damage and vital to cell survival. We conclude from these results that association of ZnPc with serum components can have important, and widely differing, effects on both degree of uptake and cellular distribution of the photosensitizer.  相似文献   

12.
The phototoxicity of sulfonated aluminum naphthalocyanines towards V-79 Chinese hamster cells is investigated. The disulfonated naphthalocyanine exhibits similar photostability, but better cell penetrating properties than the tetrasulfonated dyes. The capacity of the naphthalocyanines to generate singlet oxygen is comparable to that of the corresponding phthalocyanines. However, in contrast to the phthalocyanine dyes, the sulfonated aluminum naphthalocyanines show very little phototoxicity towards the V-79 cells, suggesting close association with non-vital cell constituents or extensive formation of photoinactive adducts and aggregates.  相似文献   

13.
14.
新型吡唑甲酰脲类化合物的合成及其生物活性   总被引:3,自引:0,他引:3  
新型吡唑甲酰脲类化合物的合成及其生物活性刘长令张立新刘武成张弘(化工部沈阳化工研究院沈阳110021)关键词吡唑甲酰脲合成生物活性中图分类号O626.21苯甲酰脲类杀虫剂是众所周知的,对人类和环境安全性极高的一类杀虫剂,被誉为二十一世纪的农药,这是由...  相似文献   

15.
Abstract There is a need to improve the selectivity of photodynamic therapy and for better targeting of tumor cells within specific tumor compartments. Selective in vitro phototoxicity of a human bladder carcinoma cell line 647V has been achieved by targeting sulfonated aluminum phthalocyanines (AlSPc) with monoclonal antibodies. Aluminum tetra-3 sulfonyl chloride phthalocyanine (PC) or rhodamine sulfonyl chloride were directly coupled to antibodies by a sulfonamide linkage and AlSPc or carboxyfluorescein were encapsulated in liposomes of the small unilamellar vesicle type (SUV) bearing antibody. Antibody E7 (IgM subclass), which recognized an antigenic determinant expressed on 647V but was absent on T24 a control human bladder carcinoma cell line, and a control IgM antibody were used. The effects of the two types of conjugate were compared. Immunofluorescence studies on living cells demonstrated specific cell surface localization of conjugates at 4°C and internalization at 37°C. Phototoxicity was measured by 3-(4,5-dimethylthiazol-2–5-diphenyltetrazolium) bromide assay after exposing A1SPc-sensitized cells to red light. Significant AlSPc dose-dependent phototoxicity of the order 4°C < 4°C plus 37°C < 37°C was observed with E7-SUV and E7-PC in the range 1–8 μM AlSPc. At equimolar AlSPc doses absolute toxicity was similar for the two conjugate types, but at equimolar antibody doses, the liposomal conjugate was more effective by up to 13-fold. Addition of urine during illumination decreased toxicity, which was attributed to the presence of protective elements. The results suggest that photosensitizers such as AlSPc could be used for antibody-directed therapy and in particular for selectively damaging tumor cells of the epithelial cell compartment in bladder carcinoma by intrabladder administration. The therapeutic ratio, which takes into account both specific and nonspecific toxicity, was greater for the liposome conjugate than for the direct conjugate indicating their greater suitability for in vivo instillation.  相似文献   

16.
The cellular photosensitivity caused by aluminum phthalocyanines sulfonated to different degrees (AlPcSn) has been investigated. The phototoxic effect increased with decreasing number of sulfonate groups on the macrocycle, with the exception of AlPcS1 which was less phototoxic than AlPcS2 but more phototoxic than AlPcS3 and AlPcS4. The tendency of the AlPcSns to aggregate in our cellular system increased with increasing lipophilicity of the sensitizers. The aggregates had little or no photosensitizing activity. The low efficiency of cell inactivation caused by AlPcS1 can be explained by the highly aggregated state of this sensitizer in the cells. AlPcS2 and AlPcS3 induced a lower degree of cell inactivation per fluorescing quantum and per quantum absorbed by monomeric species than did AlPcS2 and AlPcS1. AlPcS4 and AlPcS3 are therefore suggested to be in different intracellular locations than AlPcS2 and AlPcS1.  相似文献   

17.
The role of base modification in yeast tRNAAl(?) function in protein synthesis was examined by the use of unmodified tRNA analogues. Unmodified full length tRNAs, 5'-half tRNAs (nucleotides 1-35) and 3'-half tRNAs (nucleotides 37-75) were transcribed in vitro using T7-RNA polymerase. Unmodified tRNA half molecules were joined to normally modified half molecules (5'-half, nucleotides 1-36; 3'-half, nucleotides 36-75) by T4-RNA ligase. Using this method, we synthesized three analogues of yeast tRNAAl(?): (i) tRNAAl(?) which lacks base modifications in the 5'-half of the molecule; (ii) tRNAAl(?) which lacks base modifications in the 3'-half of the molecule; and (iii) tRNAAla completely lacking base modifications. We determined the biological activities of these analogues. In rat aminoacyl-tRNA synthetase reactions, the alanine acceptance activity decreased by 52%, 79% and 85% when modified bases were absent from the 5'-half molecule, the 3'-half molecule or the total molecule, respectively. In rabbit retic  相似文献   

18.
含氮杂环三烃基锡衍生物的合成及其生物活性   总被引:8,自引:3,他引:8  
本文合成了14个含氮杂环三烃基锡衍生物,红外光谱,核磁共振谱和质谱的研究表明三烃基锡-1,2,4-三氮唑为以氮原子作桥联的五配位聚合结构化合物,化合物的生物活性和生物选择性主要取决于锡原子上的三烃基。  相似文献   

19.
The photocytotoxicity of sulfonated phthalimidomethyl aluminum phthalocyanine, a more hydrophobic photosensitizer as compared to phthalocyanine substituted with sulfonate groups only, was investigated. Inclusion of 1-2 phthalimidomethyl groups into disulfonated aluminum phthalocyanine, resulted in increased partition coefficients between n-octanol and water, and a six-fold increase in both cellular uptake and photocytotoxicity towards Chinese hamster lung fibroblast cells (line V-79). Reducing the number of phthalimidomethyl groups, or increasing the degree of sulfonation, lead to a decrease in the partition coefficient, cellular uptake, and phototoxicity. The quantum yield of singlet oxygen was comparable for all dyes tested in this series, indicating that no significant change in this photophysical parameter resulted from phthalimidomethylation. These results suggest that the addition of 1-2 phthalimidomethyl groups to disulfonated aluminum phthalocyanine improves cellular uptake, but, as the relative efficiency of cell killing was not effected, the intracellular distribution on photosensitive molecules may not be modified.  相似文献   

20.
Ding  J.  Li  B.  Zeng  C.  Song  Y.  Xia  K.  Ai  Y.  Zhu  J.  Zhong  H.  Zhou  Z. 《Journal of Structural Chemistry》2022,63(9):1409-1423
Journal of Structural Chemistry - A pair of C9-C10-trans-C10-artemisinin-purine hybrids (A and B) were stereoselectively synthesized under a protonic acid condition, which were structurally...  相似文献   

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