微波辐射法制备N-亚水杨基壳聚糖Schiff碱及其吸附性能的研究

微波辐射法制备N-亚水杨基壳聚糖Schiff碱及其吸附性能的研究;壳聚糖;微波辐射;水杨醛;Schiff碱     

Schiff碱铜配合物的生物活性

Schiff碱及其铜配合物以良好的生物活性而被人们广泛地研究. 综述了Schiff碱铜配合物作为医药和农药的活性, 并就其发展尤其在农药方面进行了展望.     

冠醚化Schiff碱

综述了冠醚化Schiff碱的合成、配位和某些仿生性能的研究进展。     

Schiff碱配合物的研究：Ⅶ.硅胶表面Schiff碱的配位作用

有机高分子Schiff碱对金属离子的螯合作用已引起人们的兴趣。硅胶为无定形高比表面无机高分子,通过氯甲基化,可进行多种化学反应而形成各种表面基团。本文报道四种新型硅胶表面Schiff碱(图1),考察了它们对Cu~(2 ),Co~(2 ),Cd~(2 )和Pb~(2 )的配位作用。     

含羟基取代基的Schiff碱捕获自由基性能

研究了8个含羟基取代基的Schiff碱捕获自由基——ABTS .和DPPH——的性能。结果发现,Schiff碱捕获自由基的性能首先与分子中所含有的羟基的个数有关,随着羟基数目的增多,Schiff碱捕获自由基的能力增强。大的共轭体系以及羟基处于N原子邻位可增强该Schiff碱捕获ABTS .的性能;但对于捕获DPPH来说,只有同时将大的共轭体系与处于N原子邻位的羟基结合在同一分子中,才能表现出较强的捕获DPPH的性能。由此可见,DPPH对于检测Schiff碱中羟基捕获自由基的性能是一种更为专一的试剂。     

Schiff碱螯合树脂的合成及其对金属离子的吸附规律

以交联聚苯乙烯为母体的大孔螯合树脂的合成及其应用已有文献报道,我们根据光亮镀镍工艺的特定要求,合成了4种对Cu~(2+)具有良好吸附性能的Schiff碱大孔新型螯合树脂。     

Schiff碱在金电极上的自组装膜

本文利用自组装技术，首次将带有巯基的Schiff碱自组装到Au电极的表面；并利用扫描电子的显微电镜（SEM）直接证实了Schiff碱的成膜，用循环伏安和交流阻抗技术对其膜的致密性等进行了分析，证实由Schiff碱形成的膜虽较疏松，但对异相电子转移起到了一定的抑制作用，本工作为利用自组装膜的方法研究了Schiff碱提供了必要的实验理论参考。     

一种制备Schiff碱的新型方法

介绍了一种制备Schiff碱的新型方法——超音速气流固相法,其原理是在超音速气流下使芳醛和芳胺在反应器中摩擦活化,再通过撞击固定靶产生迅速的能量交换而发生化学反应.利用该方法成功制备了两种对氨基苯甲酸类Schiff碱,采用DTA对其反应进行了定性分析,并用IR、MS、1HNMR表征产物的结构,实验结果显示该方法制备Schiff碱无需溶剂,操作简单,反应时间短,转化率高.     

邻香兰素氨基酸Schiff碱化合物的合成及构象研究

Schiff碱是指含有亚甲氨基－PC＝N－的化合物,这类化合物因Schiff于1864年首先发现而得名。一些Schiff碱及其过渡金属配合物对肿瘤和病菌有一定的抑制作用^[1-3]。1970年,Hodnett^[4,5]制得几种Schiff碱,实验发现它们对老鼠肌肉内的Walker206瘤有抑制生长的作用,它们和某些金属形成的螯合物效果更好。Schiff碱配体可以作为螯合剂、生物活性剂、分析试剂和催化剂等,在科学研究和化工生产中有着广泛应用^[6,7]。本文报道一类新型的Schiff碱－邻香兰素氨基酸化合物的合成和构象研究,采用分子动力学模拟退火搜索方法对4人邻香兰素Schiff碱化合物的不同构型分子进行了构象研究,在搜索出的系列低能构象中分别找出全局最低能量构象,以此为初始构象进行了PM3量子化学计算。4个化合物的分子骨架结构如图1所示。     

水杨醛缩牛磺酸Schiff碱和还原Schiff碱的合成、晶体结构及其荧光性质

在甲醇溶液中,水杨醛和牛磺酸经缩合反应合成了水杨醛缩牛磺酸Schiff碱(1);1用硼氢化钠还原制得对应的其还原Schiff碱(2).1和2的结构经1H NMR,IR和元素分析表征.X-射线单晶衍射分析表明,2属单斜晶系,空间群P21/c,晶胞参数a=10.787 4(12)A,b=8.989 7(10)A,c=11....     

PREPARATION AND PURIFICATION OF SCHIFF BASE AND PROTONATED SCHIFF BASE FROM 9-CIS-RETINAL

A modified method for preparation and purification of Schiff base and protonated Schiff base from 9-cis-retinal has been suggested. Reaction took place in chloroform phase and purification was conducted by using water to remove the excess solvent, base and acid.     

Lanthanide Compounds with SCHIFF Bases and with Copper(II) SCHIFF Base Complexes as Ligands

Lanthanide adducts with N,N′-bis(salicylidene)-1,3-propylendiamine and N,N′-bis(salicylidene)-1,3-propylendiamine-2-olo have been prepared. It is noted that the molecules, and not anions, of the SCHIFF bases are coordinated with the metal ion. Bi- and trinuclear lanthanide complexes with the “complex ligand”, N,N′-1,3-propylen-bis-(salicylideniminato)copper(II), coordinating as a bidentate ligand, have also been isolated. The compounds have been characterized by elemental analyses, molar conductance, electronic and infrared spectra. Possible structures for the complexes have been proposed.     

FT-IR SPECTRA OF THE SCHIFF BASES and PROTONATED SCHIFF BASES OF 1-cis- and 7,9-DIcis-RETINAL

Abstract— We have prepared and recorded the FT-IR spectra of the Schiffand protonated SchifT bases of 1-cis- and 7,9-dicw-retinal. Analyses of the spectra were aided by corresponding spectra of three deuterated analogs and the retinal isomers. The vibrational assignments of the latter have now been supported by results from normal mode calculations.     

Schiff碱配合物的研究——Ⅸ.表面Schiff碱配合物对H_2O_2分解的催化作用

制备了两种表面Schiff碱及其Cu~(2+)、Co~(2+)、Ni~(2+)、Zn~(2+)配合物,考察了它们对H_2O_2分解的催化性能,其活性顺序为:Co~(2+)>Cu~(2+)>Ni~(2+)>Zn~(2+),且与金属离子氧化还原电位有关。溶液的pH值增加有利于催化反应,有机配体的加入则对反应有所抑制。     

Schiff碱配合物的研究——Ⅸ.表面Schiff碱配合物对H2O2分解的催化作用

制备了两种表面Schiff碱及其Cu²⁺、Co²⁺、Ni²⁺、Zn²⁺配合物,考察了它们对H₂O₂分解的催化性能,其活性顺序为:Co²⁺>Cu²⁺>Ni²⁺>Zn²⁺,且与金属离子氧化还原电位有关。溶液的pH值增加有利于催化反应,有机配体的加入则对反应有所抑制。     

THE PROTONATION OF A RETINYL SCHIFF BASE

The hydrogen bonding-protonation equilibrium for retinyl Schiff base/propionic acid or 3-chloropropionic acid systems was examined by Fourier transform infrared spectroscopy in non polar solutions at temperatures ranging from 25 degrees C to about -150 degrees C. The spectra give evidence for the gradual increase in the degree of protonation as temperature is lowered. The bearing of this on applying low temperature spectroscopic results to physiological conditions in rhodopsin research is discussed.     

EXPERIMENTAL and THEORETICAL STUDIES OF SCHIFF BASE CHLOROPHYLLS

Abstract— A protonated Schiff base of Ni (II)-pyrochlorophyll a has been synthesized which exhibits a reversible bathochromic shift of 504 cm^-1 relative to Ni (II)-pyrochlorophyll a. The magnitude of this shift lies between those observed for P700 and P680, the photoactive pigments of photosystems I and II in plants. Cyclic voltammetric measurements show that the protonated Schiff base is about 0.2 V more difficult to oxidize than its unprotonated form. These results suggest that a protonated Schiff base may be a better model for P680 than, as was originally assumed, for P700. In addition, the results of solvent and counterion effect studies show that microenvironmental perturbations in the neighborhood of the protonated Schiff base moiety are unlikely to induce further spectral shifts. Ab initio quantum mechanical calculations show a small hypsochromic shift rather than the observed bathochromic one, and the reasons for this discrepancy are discussed.     

BATHOCHROMICITY OF RETINAL SCHIFF BASES IN CELLULOSE MATRIX

Abstract Schiff bases of all-trans-retinal (formed with n-butylamine, tryptamine and β-naphthylamine) and of benzaldehyde, trans -cinnamaldehyde and all- trans -retinal with aniline exhibit an appreciable red shift in their UV-visible maxima on intercalation in cellulose matrix relative to their absorption in solution in the absence of acid. Treatment of these model compounds with trichloroacetic acid in solution gives the corresponding protonated salts. The red shift due to the cellulose environment is, however, less than the red shift in acid solutions. However, an exception is all- trans-N -retinylidenetryptamine for which the red shift in cellulose is quite close to the corresponding value for the protonated salt in heptane and methanol. N -Benzalideneaniline and trans- N -cinnamalideneaniline, with shorter polyenic moieties, tend to show a greater bathochromic shift in cellulose. all-trans- N -Retinylidene- n -butylamine, all- trans-N -retinylidenetryptamine and all- trans-N -retinylidene-β-naphthylamine show a reduced bathochromic shift when intercalated in cellulose pretreated with a base such as n -butylamine. The chromophore of all- trans-N -retinylidenetryptamine is stabilized by the presence of the indole moiety. These results indicate the importance of hydrogen-bond interactions at the chromophore sites of rhodopsins. A mechanistic proposal for explaining protonation, stability and wavelength regulation in the opsin family of proteins is discussed.