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1.
本工作对N-苯基-N'-乙基呱嗪作为酮/胺光引发体系中组分之一的作用机制进行了研究。发现该特殊的胺类化合物虽包括二甲基苯胺和三乙胺两个部分,但它和酮类相组合形成的光引发体系只有较低的尤引发速率。对上述现象进行了讨论,并通过加入酸类化合物使其中一个胺发生季胺盐化,用以改进光引发效率来进一步证实文中所讨论的机制。  相似文献   
2.
新型氮芥和卤代烷基哌嗪芳香醛的合成   总被引:1,自引:0,他引:1  
通过对Vilsmeier反应、烷基化反应和氯化反应的改进提出了以简单易得的苯胺和苯基哌嗪为原料制备氮芥和哌嗪芳香醛的方法. 采用该改进的方法合成了8个氮芥和哌嗪芳香醛, 其中7个为新化合物. 它们的结构均经质谱、红外光谱、核磁共振谱和元素分析确证.  相似文献   
3.
哌嗪取代卟啉的合成、表征及其抗癌活性   总被引:2,自引:0,他引:2  
李和平  郭灿城  阮建明  黄伯云 《有机化学》2004,24(7):783-787,J003
设计并合成了6个具有抗癌活性的哌嗪取代卟啉化合物,分别为5,10,15,20-四[4-(4'-乙基哌嗪基)苯基]卟啉(TEPPH2,8a),5,10,15,20-四[4-(4'-丁基哌嗪基)苯基]卟啉(TBPPH2,8b),5,10,15,20-四[4-(4'-庚基哌嗪基)苯基]卟啉(THPPH2,8c),5,10,15,20-四[4-(4'-苯基哌嗪基)苯基]卟啉(TPhPPH2,8d),5-[4-(4'-乙基哌嗪基)苯基]-10,15,20-三苯基卟啉(EPTPPH2,8e)和5-[4-(4'-丁基哌嗪基)苯基]-10,15,20-三苯基卟啉(BPTPPH2,8f).这些卟啉化合物都由取代苯甲醛与吡咯缩合而成,每一个卟啉分子中含有一个或四个具有抗癌活性的取代哌嗪结构,结构经元素分析,MS,1H NMR,IR和UV-vis等表征.初步的生物活性研究表明,这些化合物具有一定的抗癌活性,因而在医学上可能具有潜在应用前景.  相似文献   
4.
The effect of pH on the formation and stability of phospholipid coatings in fused-silica capillaries in electrophoresis was investigated. A liposome solution consisting of 3 mM of 80:20 mol% phosphatidylcholine/phosphatidylserine (PC/PS) in N-(2-hydroxyethyl)piperazine-N'-(2-ethanesulfonic acid) (HEPES) buffer was used as coating material. The coating was prepared by a method described earlier and five steroids were used as neutral model analytes. First, the effect of pH of the coating solution on the formation and stability of phospholipid coatings was studied at pH 6.5-8.5. The pH of the background electrolyte (BGE) solution (HEPES) was either kept constant at pH 7.4 or made similar to the pH of the liposome coating solution. Results showed that attachment of the coating on the fused-silica wall mostly depends on the protonation of amines of the phospholipids and HEPES. The ability of the phospholipid coating to withstand changes in pH was then investigated by coating at pH 7.5 and separating steroids with acetic acid, 3-(cyclohexylamino)-1-propanesulfonic acid (CAPS), HEPES, or glycine BGE, adjusted to pH between 4.5 and 10.8. The results showed that with use of BGE solution at pH 10.8, the separation of steroids was not successful and the electroosmotic flow was high because of leakage of the phospholipid coating during preconditioning of the capillary with BGE solution. There was no phospholipid leakage with a BGE solution of pH 4.5, indicating that the protonated form of the functional groups of PS and HEPES participating in the attachment of the phospholipid coating to the capillary play an essential role in the success of the coating.  相似文献   
5.
陆明  魏运洋  吕春绪 《有机化学》1995,15(4):408-410
本文以乙二胺, 乙二醛和脲为原料, 通过Mannich反应, 合成出2,5,7,9-四氮杂双环[4.3.0]壬-8-酮盐酸盐(1); 化合物1 亚硝化给出2,5-二亚硝基-2,5,7,9-四氮杂双环[4.3.0]壬-8-酮(2); 硝化化合物2制得2,5,7,9-四硝基-2,5,7,9-四氮杂双环[4.3.0]壬-8-酮(3); 化合物3水解制得1,4-二硝基-2,3-二硝胺基哌嗪(4).  相似文献   
6.
The thermal behaviour of some Cu(II) compounds formed with 1,4-disubstituted piperazine derivatives has been studied. The investigations were performed on a MOM 1500 derivatograph. The endothermic effects observed at 170–180°C are associated with the processes of dehydration and dehalogenation of the compounds, with general formula LH2·CuCl4·H2O, whereL is the piperazine derivative. The residue at 600°C remains relatively constant.  相似文献   
7.
The World Health Organization issued a nitrosation procedure (NAP Test) which allows to carry out nitrosation under standard conditions. It has proved that the in vitro reaction rates of the fast nitrosatable drugs piperazine, cimetidine and ethambutol are not influenced by -, - and -cyclodextrin. On the contrary, -, -cyclodextrin and heptakis-2,6-di-O-methyl--cyclodextrin enhance the nitrosation of the slower nitrosatable 1-ephedrine and fencamfamine significantly. This possible reaction must be considered if nitrosatable drugs are formulated with cyclodextrins to be administered to human beings.  相似文献   
8.
9.
2-Nitrodiene compound 1 was stirred with p-fluorothiophenol for a long time and compound 3 was obtained. Compound 1 gave bis(thio)substituted 2-nitrodiene compound 4 and tris(thio)substituted compound 5 with 2 moles of p-fluorothiophenol in the presence of NaOH in ethanol. The compounds 9a–g have been prepared from 8a–g and 3. Compound 7 was obtained from the reaction of mono(thio)substituted 2-nitrodiene with morpholine. Compound 3 gives 11a–d in the reaction with piperidines in CH2Cl2 (or ether). Compound 13a–b have been obtained from the reaction of compound 3 with primary amines 12a–b. Compound 3 gives 15 and 16 in the reaction with 2,5-dimethylpiperazine in CH2Cl2.

  相似文献   
10.
In an attempt to find new dual acting histamine H3 receptor (H3R) ligands, we designed a series of compounds, structurally based on previously described in our group, a highly active and selective human histamine H3 receptor (hH3R) ligand KSK63. As a result, 15 obtained compounds show moderate hH3R affinity, the best being the compound 17 (hH3R Ki = 518 nM). Docking to the histamine H3R homology model revealed two possible binding modes, with key interactions retained in both cases. In an attempt to find possible dual acting ligands, selected compounds were tested for antioxidant properties. Compound 16 (hH3R Ki = 592 nM) showed the strongest antioxidant properties at the concentration of 10−4 mol/L. It significantly reduced the amount of free radicals presenting 50–60% of ascorbic acid activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, as well as showed antioxidative properties in the ferric reducing antioxidant power (FRAP) assay. Despite the yet unknown antioxidation mechanism and moderate hH3R affinity, 16 (QD13) constitutes a starting point for the search of potential dual acting H3R ligands-promising tools for the treatment of neurological disorders associated with increased neuronal oxidative stress.  相似文献   
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