微波干法催化芳香醛与绕丹宁及N－苯基绕丹宁的缩合反应

利用微波辐射和固体碱性载体试剂催化绕丹宁及Ｎ－苯基绕丹宁和芳香醛的缩合反应合成了１４个绕丹宁衍生物并研究了影响反应的因素。     

醛基螺苯并吡喃与绕丹宁的反应

醛基螺苯并吡喃与绕丹宁的反应李仲杰,刘祥（西北大学化学系,西安,７１００６９）关键词醛基螺苯并吡喃,绕丹宁,反应机理醛基螺苯并吡喃具有光致变色性质［１］．利用醛基的反应对其结构进行修饰,有可能获得新的功能分子。这类化合物与Ｗｉｔｔｉｇ试剂的反应已有报...     

苄叉绕丹宁及其类似物的N—Mannich碱合成

Mannich 反应在有机合成中占有重要地位。通过 Mannich 反应合成的化合物可以具有止痛、杀菌、杀虫、抗癌等多种生物效应。在应用 N-Mannich 反应合成的斑蝥素类似物和绕丹宁衍生物中,有些化合物具有抗癌活性。绕丹宁分子中活泼亚甲基及酰亚胺两个部位均可进行 Mannich 反应,提供新的结构类型     

2-芳基亚甲基绕丹宁的催化合成和紫外光谱的取代基效应

在 KF- A12 0 3负载型固体碱催化下 ,绕丹宁和芳香醛发生缩合反应 ,高产率地合成了 5-芳基亚甲基绕丹宁 ,测定了产物在种溶剂中的紫外光谱 ,其最大吸收频率νmaxuv与 Hammett取代基常数σ+p存在良好的线性关系。     

应用绕丹宁衍生物测定贱金属研究的国内现状

绕丹宁衍生物是光度法测定贵金属的一类传统显色剂,这类试剂容易合成,近年来涌现出一批新型绕丹宁衍生物,除测定贵金属外,已拓展到一些贱金属的分析测定.分析手段已由传统的吸光光度法向荧光光度法和催化动力学荧光分析法转移,使测定的灵敏度和选择性大大提高.根据文献检索,将国内在这一领域的研究应用现状进行介绍.     

新荧光试剂5-(4'-卤代-2'-羧基苯偶氮)绕丹宁的合成及分析化学特性研究

合成了三种新荧光试剂,5-(4'-氯-2'-羧基苯偶氮)绕丹宁(CRACP.2).5-(4'-溴-2'-羧基苯偶氮)绕丹宁(BRACP,3)及5-(4'-碘-2'-羧基苯偶氮)绕丹宁(IRACP,4).研究了它们的吸收光谱及荧光性质.探讨了分子结构与荧光性能的关系.建立了铜(Ⅱ)的荧光分析方法.在pH5.3时.CRACP与铜( Ⅱ) 形成荧光螯合物, λ~ e~ x/ λ~e~m=310nm/408nm.检测限为5×10^-^4μg/g.     

新荧光试剂5-(4''-卤代-2''-羧基苯偶氮)绕丹宁的合成及分析化学特性研究

合成了三种新荧光试剂,5—(4’—氯—2’—羧基苯偶氮)绕丹宁(CRACP,2)、5—(4’—溴—2’—羧基苯偶氮)绕丹宁(BRACP,3)及5—(4’—碘—2’—羧基苯偶氮)绕丹宁(IRACP,4).研究了它们的吸收光谱及荧光性质,探讨了分子结构与荧光性能的关系.建立了铜(Ⅱ)的荧光分析方法.在pH5.3时,CRACP与铜(Ⅱ)形成荧光螫合物,λ_(ex)/λ_(em)=310nm/408nm,检测限为5×10 ~(-4)μg/g.     

RE（Ⅲ）与5—（2‘—羧基苯偶氮）绕丹宁及其衍生物的配合物稳定常数

采用ｐＨ－电位滴定法研究了乙醇溶液中ＲＥ（Ⅲ）与新型荧试剂Ｈ２Ｌ［５－（２＇－羧基苯偶氮）］绕丹宁（Ｂｒ－ＲＡＣＰ）、５－（４＇－氯代－２＇－羧基苯偶氮）绕丹宁（Ｃｌ－ＲＡＣＰ）、５－（４＇－溴代－２＇－羧基苯偶氮）绕丹宁定常数大小为ＲＡＣＰ＞Ｃｌ－ＲＡＣＰ＞Ｂｒ－ＲＡＣＰ。而与Ｎｄ（Ⅲ）的累积生成常数ｌｇβｍｌｈ随原子序数Ｚ增大时，研究了浓度对ｌｇβｍｌｈ的影响，测定了１５种稀土与ＲＡＣＰ的ｉｇ     

对二甲胺基苯叉绕丹宁萃取滴定法测定矿石中微量银

对二甲胺基苯叉绕丹宁(PDABR)为指示剂,间接测定氰根已有报导。本文由此出发,拟定在pH5.5的乙酸-乙酸铵绥冲液中用PDABR-四氯化碳标准溶液萃取滴定矿石中微量银。汞(Ⅱ)、金(Ⅲ)、钯(Ⅱ)和铂(Ⅳ)与PDABR作用干扰测定;氯、     

一类新的贵金属显色剂——若丹宁偶氮同系物

若丹宁偶氮同系物是七十年代发展起来的一类新光度显色试剂。这类试剂与贵金属离子的显色反应具有很高的灵敏度和选择性。到目前为止,Саввин等人已发表了20余篇关于这类试剂的合成、性质和分析应用方面的研究报导。已研究过的这类化合物有:若丹宁偶氮化合物、硫代若丹宁偶氮化合物、3-取代若丹宁偶氮化合物和硫代丙酰若丹宁偶氮化合物。它们的结构通式如下:A.若丹宁偶氮化合物     

Three-component one-pot synthetic route to 2-amino-5-alkylidene-thiazol-4-ones

A fast and straightforward three-component reaction to 2-amino-5-alkylidene-thiazol-4-ones is described. The one-pot methodology, reported for the first time, involves Knoevenagel condensation of aromatic aldehydes and rhodanine followed by displacement of the thiocarbonyl sulfur with primary or secondary amines in the same reaction mixture. The reactions were performed using a dedicated microwave reactor, which enabled short reaction times and easy work-up.     

A practical access to novel 2-amino-5-arylidene-1,3-thiazol-4(5H)-ones via sulfur/nitrogen displacement under solvent-free microwave irradiation

A new effective approach to the synthesis of a small library of 2-amino-5-arylidene-1,3-thiazol-4(5H)-ones was reported using solvent-free reaction conditions under microwave irradiation. In the first step, rhodanines were subjected to Knoevenagel condensation with aryl aldimines according to a facile one-pot protocol. Then the (5Z)-5-arylidene rhodanine derivatives were transformed directly into the corresponding 2-amino-1,3-thiazol-4(5H)-ones by sulfur/nitrogen displacement reaction under microwaves with retention of configuration and good overall yields.     

Green synthesis of 5-benzylidene rhodanine derivatives catalyzed by 1-butyl-3-methyl imidazolium hydroxide in water

A basic functionalized ionic liquid, 1-butyl-3-methyl imidazolium hydroxide ([bmim][OH]), catalyzed the Knoevenagel condensation of rhodanine with aromatic aldehydes. It proceeded smoothly in water to afford the 5-benzylidene rhodamine derivatives in high yields at room temperature. This new method offers several advantages, such as excellent yields, short reaction times, and simple procedure. The catalyst can be reused at least 5 times without significant loss of activity. Correspondence: Zu-liang Liu, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P.R. China.     

微波干法催化醛酮与胺的缩合反应

利用微波辐射和固体中性Al2 O3 载体催化醛酮与胺的缩合反应的方法合成了十六种亚胺 ,研究了微波功率、作用时间、产物提取方式等因素对反应的影响 ;与无微波作用的一般合成方法相比 ,该法明显地提高反应速度及产率 ;文中用低极性熔点递变物质灌装毛细管的方法观测微波作用下反应温度 ,探讨微波作用化学反应的机理 ,其机理除与微波加热作用有关外还与分子间氢键及分子的缔合性有关。     

脱氧胆酸裂口分子的微波合成

以固体K2CO3为载体,在微波辐射无溶剂条件下,脱氧胆酸甲酯与芳酰氯反应合成了9个新的脱氧胆酸裂口分子人工受体,其结构经1H NMR,IR,MS及元素分析表征.     

Condensation of rhodanine withβ-dicarbonyl compounds

Reaction of acetylacetone with rhodanine in ethanol solution, in the presence of ammonia and ammonium chloride gives two condensation products, containing one or two rhodanine groups. Under the same conditions benzoylacetone condenses with one molecule of rhodanine. Methylation of these compounds with methyl iodide takes place at an exocyclic sulfur atom, to give mono- and dimethylmercapto derivatives. The condensation products from the above carbonyl compounds and rhodanine have an active methylene group which can react with nitroso compounds and diazonium salts.     

Reaction of 2-pyridine aldehyde with rhodanines

Reaction of 2-pyridine aldehyde or its methiodide in methanol solution in the presence of piperidine with rhodanine or 3-alkylrhodanines leads to crotenoid condensation and formation of 2-pyridinylidene-5-rhodanine and 2-pyridinylidene-5-(3-alkyl) rhodanines and their monomethiodides.     

Synthesis of isothiocoumarin derivatives

A method was developed for the synthesis of 1-oxo-1H-isothiochromenes from 2-benzofuran-1(3H)-one (phthalide). 3-Bromo-6-chloro- and 3,6-dibromo-2-benzofuran-1(3H)-ones were prepared by the bromination of 6-chloro- and 6-bromo-2-benzofuran-1(3H)-ones and were converted by hydrolysis into 5-chloro- or 5-bromo-2-formylbenzoic acids. The condensation of these acids with rhodanine followed by recyclization gave 7-chloro- and 7-bromo-1-oxo-1H-isothiochromene-3-carboxylic acids.     

饶丹宁甲叉基取代左氧氟沙星衍生物的合成与抗肿瘤活性

为寻找提高氟喹诺酮肿瘤活的有效结构修饰策略,左氧氟沙星(3)的衍生物(S)-(-)-9-氟-2,3-二氢-3-甲基-10-(4-甲基-1-哌嗪基)-[1,4]噁嗪并[2,3,4-ij]-喹啉-7(4 H)-酮-6-甲醛(5)与饶丹宁类(2a-2l)通过Claisen-Schmid缩合反应构建了饶丹宁甲叉基取代左氧氟沙星衍生物(6a-6l)目标化合物,其结构经元素分析和光谱数据确证。体外初步抗细胞增殖活性筛选结果表明,12个新目标化合物对人非小细胞肺癌细胞(A549)、人肝癌细胞(Hep-3B)、人胰腺癌细胞(Capan-1)和人白血病细胞(HL60)的活性高于母体左氧氟沙星,且对正常细胞Vero表现出较低细胞毒作用。构效关系表明,卤代苯基或饶丹宁或环丙基饶丹宁化合物的活性强于其它取代,尤其环丙基化合物对A549的活性与对照阿霉素相当。因此,饶丹宁甲叉基替代C-3羧基有利于提高氟喹诺酮的抗肿瘤活性,发展了氟喹诺酮结构修饰的新途径。     

Synthesis and antifungal evaluation of novel dicyanoderivatives of rhodanine

This work describes the synthesis and antifungal evaluation of 5‐arylidene‐(Z)‐2‐(1,1‐dicyanomethylene)‐1,3‐thiazol‐4‐ones 5 obtained from the reaction of 2‐(1,1‐dicyanomethylene)‐1,3‐thiazol‐4‐one 3 and benzaldehydes 4. The starting material 3 was synthesized by a condensation reaction of rhodanine 1 and malononitrile 2. The structures of the obtained products were established by IR, NMR, mass spectrometry, and elemental analysis. J. Heterocyclic Chem., (2011).