含硫脲基对称与不对称双Schiff碱及其配合物研究

【作者】 李琳；

【导师】 王麟生；

【作者基本信息】 华东师范大学 ， 无机化学， 2004， 硕士

【摘要】 Schiff碱中由于含有(?)C=N基团，使它有许多特点：例如，氮上具有π和SP~2杂化轨道上的孤对电子，易配位、易形成环状结构等，因此合成这种Schiff碱具有重要的生物学与化学意义。迄今国内外化学工作者不断开展此领域的工作，合成了各类Schiff碱及其金属配合物，并研究和开发了其多方面的用途。在药物、催化、材料、生物机理模拟、分析滴定等方面的应用，已见之于报道。其中含硫Schiff碱及其配合物具有抑制细菌生长、抗肿瘤的良好功能，日益引起了人们的注意。 本文以对称的二胺类-1，3-二氨基硫脲为反应前体，由于两个氨基具有相同的反应活性，容易生成两边对称的双缩合Schiff碱。以1，3-二氨基硫脲与含有不同取代基的水杨醛类(控制醛与氨的物质的量之比1∶2)发生反应时，直接合成了五种对称的双Schiff碱。如果控制反应条件，把不易与之发生亲核反应的酮-乙酰基吡啶慢慢滴加到过量的1，3-二氨基硫脲中(两者物质的量之比为1∶1)，可一步反应得到单缩合产物。这种单缩合产物由于含有自由的氨基，又可以与含有不同吸电子、给电子效应取代基的水杨醛类发生缩合反应，通过两步反应得到了不对称双Schiff碱。这提供了一种合成不对称双Schiff碱的一种简单易行的方法。对上述化合物进行了熔点、红外光谱、质谱、元素、核磁共振等测试，确定了其组成和可能的结构。其中九种化合物均未见文献报道。此外，以不对称双Schiff碱系列中的2e和对称双Schiff碱系列中3e为代表，合成了其金属盐Ni(Ⅱ)配合物，并对其进行了电导率、熔点、红外光谱、紫外光谱、元素分析测试，初步推测出配合物的结构。 在合成十种Schiff碱及其配合物的基础上，又测试了它们对革兰氏阳性菌(金葡萄球菌、枯草菌)和革兰氏阴性菌(大肠杆菌)的抑制情况。采用国际药典通用的管碟法(又称杯碟法)进行抑菌测试，发现上述Schiff碱均有不同程度的抑菌性能，测试了不同浓度下的抑菌圈直径大小，发现抑菌圈直径的大小并不随化合物的浓度的增大而增大，而是在一定的范围之内具有一个最佳浓度，此时的抑菌圈直径最大，两种配合物却不具有生物活性。比较了其抑菌性能的高低差异，找出各化合物表现最佳抑菌效果时的浓度，并对其抑菌机理作出了推测。更多还原

【Abstract】 Schiff base, containing the C=N group, has some specialities: its atom N with several lone pair electronson and SP2 hybridized orbit is inclined to coordinate with metals and to be ring formation. It seems to be useful to synthesize Schiff base with chemical and biological active. Up to now , research work about this field has been done by researchers in the world, who have synthesized and charactered a plenty of Schiff base and their metal complexes, studied and exploited many uses, such as medicines , catalyst , material , titrate and simulating biology mechanism et al. Schiff base containing sulfur and its complexes are given more attention because of their significant antitumor and antibacterial activities.In this paper , we use symmetrical diamine -thiocarbohydrazide as the parent reactants, symmetrical bis-Schiff bases are easily obtained because two -NH2 groups have the same activity. Five symmetrical bis-Schiff bases have been synthesized by the reaction of thiocarbohydrazide and substituted salicylaldehydes (controlling their molar ratio 1:2) directly . However, if the reaction is carried out in the condition of a slow addition of ketone- 2-acetylpyridine to an excess of thiocarbohydrazide , controlling their molar ratio 1:1, the product of monocondensation was formed firstly, The resulting product with an additional -NH2 group may be condensed with substituted salicylaldehydes. Thus five new asymmetrical bis-Schiff bases have been synthesized. It can been seen that this method offered the possibility of a simply synthetic route to asymmetrical bis-Schiff base. Melting Point ,IR , Mass spectrum, elemental analyses and 1HNMR have been tested and their composition and probably structure are confirmed. Among these, nine have not been reported by literatures. We take asymmetrical Schiff base 2e and symmetric Schiff base 3e as representation, and two Ni(II) complexes are synthesized. Electric conduct, melting point, element analysis, IR, UV, and 1HNMR are measured, and their probablystructures have been conformed.The antibacterial activities of ten Schiff bases and two complexes have been tested against gram-positive(micrococcus aurous, bacillus subtills) and gram-negative bacterium(colibacillus). Using the international codex current method (cup-plate method), we find that Schiff bases above all have anti-bacterial ability. We measure the diameter of circles of different concentration and find that the diameter of circles do not become larger when the concentration of the compound is stronger, but have the best effect hi a certain range, However, two complexes do not have biological activity. We also compare their anti-bacterial ability and find out their concentration which showing best effect and suppose their anti-bacterial mechanism.更多还原