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1.
目前在用水溶性卟啉衍生物作显色剂方面已有文献总结[1]。但对非水溶性卟啉则研究得较少。就测定痕量铅而言,皆用水溶性卟啉衍生物,而用非水溶性卟啉测定铅,则尚未见报导[2-6]。  相似文献   

2.
芳醛上的取代基对卟啉的合成及其性质的影响   总被引:5,自引:0,他引:5  
王莉红  汤福隆 《分析化学》1993,21(6):665-668
笔者合成了10种非水溶性卟啉和7种水溶性卟啉,并作一些规律性的探讨。研究表明,芳醛上取代基不同对卟啉的合成、磺化和试剂的离解平衡等有一定的影响。  相似文献   

3.
水溶性卟啉及金属卟啉在DNA中的研究进展   总被引:1,自引:0,他引:1  
张现侠  陈灿玉 《化学学报》2012,70(24):2475-2483
近年来, 卟啉及金属卟啉与DNA的相互作用已成为研究的热点. 通过对卟啉及金属卟啉与DNA相互作用的研究将有助于更深地认识DNA本身的结构和功能, 有助于卟啉及金属卟啉在医学上的应用, 对认识很多疾病的治病机制和药物的设计也起到非常重要的作用. 本文阐述了卟啉及金属卟啉与DNA相互作用的方式和影响因素, 并将水溶性卟啉及金属卟啉分为三类: 具有吡啶基或铵基的阳离子型卟啉及金属卟啉, 具有磺酸基或羧基的阴离子型卟啉及金属卟啉, 以及非离子型的卟啉及金属卟啉. 重点论述了这三类水溶性卟啉及金属卟啉与DNA之间的相互作用, 以及这三类水溶性卟啉及金属卟啉在DNA中的应用研究进展.  相似文献   

4.
以meso-四(4-吡啶基)卟啉和meso-四(4-羟基苯基)卟啉为原料,三乙二醇单甲醚单元取代和锰离子配位作为功能性修饰手段,按照优化的反应条件,高效合成了吡啶基阳离子型和磺酸基阴离子型水溶性卟啉化合物.该类方法操作简单、收率高、反应条件温和,为同类型水溶性卟啉的合成提供了很好的合成方法.  相似文献   

5.
为了建立操作简单,不用特殊装置的痕量金属定量分析方法,使用高灵敏度显色剂如卟啉衍生物(ε=2~5×10~5)光度法研究就是其中之一。就测定痕量镉而言,已报导的有TPPS_3、TPPS_4、T(4-NHCOCH_3)PP等水溶性卟啉衍生物,非水溶性卟啉衍生物用于测定痕量镉还未见报导。我们对具有新型结构的非水溶性T(4-NHCOCH_3)PP进行了合成,并  相似文献   

6.
水溶性卟啉催化氧化1,5-萘二酚   总被引:1,自引:0,他引:1  
合成并表征了系列水溶性卟啉配体[H2TPPS: 5,10,15,20-四-(4-磺酸基苯基)-21H,23H-卟啉, H2TMPyP: 5,10,15,20-四(4-吡啶基)-21H,23H-卟啉, H2TCPP: 5,10,15,20-四-(4-羧基苯基)-21H,23H-卟啉]及相应的铁、锌及钴配合物. 将水溶性卟啉作为光敏剂, 用于1,5-萘二酚的光催化反应, 产物为5-羟基-1,4萘醌. 利用UV-Vis方法对卟啉催化1,5-萘二酚的反应过程进行了监测, 探索了水相和水/二氯甲烷双相催化体系, 确定了较为理想的反应条件. 探讨了不同取代基和不同金属离子对卟啉催化性能的影响, 初步讨论了催化机理. 结果表明, 具有磺酸根阴离子取代基的水溶性卟啉具有最好的催化活性; 卟啉的催化活性与其在反应体系中的稳定性密切相关; 铁卟啉在反应初期呈现很高的催化活性, 但在光照条件下容易发生光解而导致催化活性的降低; 无金属的磺酸卟啉在催化体系中的催化活性和稳定性最好.  相似文献   

7.
贾涛  王凯  李早英 《有机化学》2003,23(Z1):273
在癌症治疗中,卟啉化合物被用作光动力疗法(PDT)的光敏试剂.人们已经致力于制备新型卟啉化合物以用于癌症的光疗法[1,2]. 人工合成的含有吡啶盐、磺酸盐或羧酸盐等取代基的水溶性卟啉化合物能够在肿瘤组织上集聚[3].在寻找更有效的光敏剂的过程中,经过修饰的水溶性卟啉及其金属衍生物,由于它们能集聚在肿瘤组织并在光照下表现出较好的光敏活性,已引起了广泛关注.  相似文献   

8.
meso-四-(3-甲基苯)卟啉与镉反应的分光光度法研究   总被引:2,自引:0,他引:2  
近年来,对于大环卟啉化合物在分析化学中的应用研究得越来越广泛。鉴于非水溶性卟啉较水溶性卟啉易于合成和提纯,我们研究了meso-四-(3-甲基苯)卟啉[T(3-MP)P]与镉的反应。结果表明,T(3-MP)P与镉的显色反应有较高的灵敏度(ε=3.8×105),是测定镉的灵敏方法之一。  相似文献   

9.
合成了两种非离子型水溶性卟啉分子,并利用它们对单壁碳纳米管(SWNTs)进行了非共价表面修饰。功能化后SWNTs能够在水中均匀分散。紫外-可见光谱、荧光光谱、透射电镜的测试结果均证明非离子型水溶性卟啉分子与SWNTs之间存在强烈的相互作用。其中,含有柔性烷基取代链的卟啉分子因与SWNTs之间存在π-π和疏水双重相互作用,所形成的复合物在水中表现出更好的分散稳定性。这种既具有水溶性又具有生物相容性和良好稳定性的功能化SWNTs,在生物医药领域具有潜在的应用前景。  相似文献   

10.
两种水溶性卟啉与DNA相互作用的研究   总被引:6,自引:0,他引:6  
卟啉化合物以其对肿瘤组织的特殊亲和性和光动力学效应受到广泛的重视,国内外这方面的研究报导甚多.自1979年Fief等人[1]证实水溶性四-(4-甲基吡啶基)卟啉及其金属配合物能嵌入DNA的碱基之后,人们以这类水溶性卟啉为模型化合物,利用各种物理和化学手段研究它们与DNA和RNA  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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