席夫碱的合成及生物活性

以对溴苯酚和苯甲酰氯为原料,经过酯化、Fries重排、缩合等一系列反应,合成了2-[(2-苯基亚氨基)苯甲基]-4-溴苯酚,该化合物分别与多种醛酮在不同条件下反应,得到了5种不对称双席夫碱和2种对称性双席夫碱。 对席夫碱化合物的抑菌活性测定表明,大部分化合物具有较强的抗菌活性,其中含硫原子的席夫碱抑菌活性最强,最小抑菌浓度均为1×10^-4 g/L。     

噻吩-2-甲醛缩L-半胱氨酸席夫碱的合成、晶体结构及量子化学研究

采用噻吩-2-甲醛分别与邻氨基苯硫酚和硫代氨基脲合成了2种噻吩-2-甲醛杂环席夫碱.利用红外光谱、紫外-可见光谱、荧光光谱、X-射线单晶衍射分析、热重分析和核磁共振氢谱等检测方法对2种目标新型杂环类席夫碱产物的结构和性质进行了表征与分析.采用量子化学中常用的密度泛函方法(DFT)对2种新席夫碱化合物进行几何优化,采用单激发组态相互作用(CIS)和含时密度泛函方法(TD-DFT)进一步优化,比较计算光谱与实际测试光谱之间的误差,探究了2种席夫碱化合物荧光发光机制,为这类席夫碱分子结构设计提供了理论依据.     

α-(1,3,4-噻二唑-5-基)氨基烃基膦酸酯的合成及生物活性

以5-氨基-2-巯基的席夫碱与亚磷酸二乙酯反应, 合成了15个新的α-(1,3,4-噻二唑-5-基)氨基烃基膦酸酯, 初步的生物活性测试表明部分目标化合物具有较好的植物生长调节活性, 其中2,4-二氯苯甲醛、呋喃甲醛和吲哚甲醛的席夫碱生成的α-氨基烃基膦酸酯具有较好的生长素活性.     

异维A酸4-氨基安替比林席夫碱酯的合成

以二环己基碳酰亚胺为脱水剂,4-二甲氨基吡啶为催化剂,异维A酸与甲酰基酚发生酯化反应生成了异维A酸酯(1a~1d);1再与4-氨基安替比林反应,合成了4个异维A酸4-氨基安替比林席夫碱酯(2a~2d)。2的结构由1HNMR,IR和MS确证。     

乙二胺-2-吡啶甲醛席夫碱钯配合物的制备、表征及其催化性能研究

摘要：本文利用2-吡啶甲醛和乙二胺制得乙二胺-2-吡啶甲醛席夫碱配体,再与钯盐作用制得乙二胺-2-吡啶甲醛席夫碱钯配合物。运用红外光谱、核磁共振、质谱、元素分析、ICP等分析手段对乙二胺-2-吡啶甲醛席夫碱配体及其钯配合物进行了表征,提出了乙二胺-2-吡啶甲醛席夫碱钯配合物的结构,并对其在Heck反应中的催化性能进行了研究。     

4-氨基-5-取代-1,2,4-三唑-3-硫酮席夫碱的合成、生物活性及分子对接

首先分别以硫代甲酰肼与冰乙酸为原料合成了中间体4-氨基-5-甲基-1,2,4-三唑-3-硫酮(M1);以取代苯甲酸为原料经过酯化、酰肼化、成盐和环化合成了中间体4-氨基-5-芳基-1,2,4-三唑-3-硫酮(M2).再将M1和M2分别与4,6-二氯-5-嘧啶甲醛进行加成-消除反应,合成了4种新型含嘧啶环的1,2,4-三唑席夫碱化合物M1-1, M2-1, M2-2和M2-3.通过元素分析、红外光谱分析及1HNMR对其进行结构表征.采用菌丝生长速率法及分子对接法研究目标化合物的生物活性及抑菌机理.结果表明,化合物对不同真菌均有一定的抑制作用.由EC_(50)值可见,化合物M1-1,M2-2和M2-3对小麦赤霉菌的抑菌效果均优于标准药物(氟康唑),且与分子对接结果相一致.     

乙二胺-2-吡啶甲醛席夫碱钯配合物的制备、表征及其催化性能研究

利用2-吡啶甲醛和乙二胺制得乙二胺-2-吡啶甲醛席夫碱配体,再与钯盐作用制得乙二胺-2-吡啶甲醛席夫碱钯配合物.运用红外光谱、核磁共振、质谱、元素分析、ICP等分析手段对乙二胺-2-吡啶甲醛席夫碱配体及其钯配合物进行了表征,提出了乙二胺-2-吡啶甲醛席夫碱钯配合物的结构,并对其在Heck反应中的催化性能进行了研究.     

新型4-芳氧基吡啶并[3′,2′∶4,5]噻吩并[3,2-d]嘧啶衍生物的合成

2-氯-3-氰基吡啶与巯基乙酸乙酯经闭环反应制得3-氨基吡啶并[3,′2′∶4,5]噻吩-2-甲酸乙酯(1);1与甲酰胺第二次成环生成吡啶并[3,′2′∶4,5]噻吩并[3,2-d]嘧啶-4-酮(2);2经氯化后与取代苯酚反应合成了12个新型的4-芳氧基吡啶并[3,′2′∶4,5]噻吩并[3,2-d]嘧啶衍生物,其结构经1H NMR,13C NMR,IR和元素分析表征。     

5-苄基-4-氨基-3-巯基-1,2,4-三唑席夫碱合成与生物活性研究

为进一步研究三唑席夫碱化合物的合成与性质,以熔融法合成中间体5-苄基-4-氨基-3-巯基-1,2,4-三唑,再与取代醛在冰醋酸催化下回流反应合成了6个1,2,4-三唑席夫碱化合物,其结构通过元素分析,红外光谱,核磁共振氢谱进行了表征。生物测试结果表明,合成的三唑席夫碱化合物对烟草赤星病、马铃薯干腐病、小麦赤霉病、番茄早疫病、西瓜枯萎病5种植物病原菌具有较好的抑菌活性。     

3-甲基-4-氨基-1,2,4-三唑-5-硫酮席夫碱的合成及生物活性研究

用自制的二氨基硫脲与乙酸反应得到3-甲基-4-氨基-1,2,4-三唑-5-硫酮, 然后以醋酸为反应溶剂和催化剂, 使之与取代芳香醛反应, 合成了8个三唑类席夫碱化合物. 通过¹H NMR, IR和元素分析对所有化合物进行了结构表征. 并对这些化合物进行了初步生物活性测试, 结果表明大部分化合物具有较好的抑菌活性, 并对席夫碱结构与活性的关系进行了探讨.     

含席夫碱的噻吩两亲分子表面活性剂的合成

在氯化亚砜存在下,2,5-二甲酸噻吩与甲醇反应得到2,5-二甲酸甲酯噻吩(1),1与水合肼反应得对应的噻吩酰肼(2),2再与辛酮缩合得到含席夫碱的噻吩两亲分子表面活性剂,其结构经1H NMR,IR和元素分析确认。     

Efficient Catalytic Reduction of 4-Nitrophenol Using Copper(II) Complexes with N,O-Chelating Schiff Base Ligands

The reduction of 4-nitrophenol to 4-aminophenol by sodium borohydride was used as a model to test the catalytic activity of copper(II) complexes containing N,O-chelating Schiff base ligands. In this study, a series of copper(II) complexes containing respective Schiff base ligands, N′-salicylidene-2-aminophenol (1), N′-salicylidene-2-aminothiazole (2), and N,N′-bis(salicylidene)-o-phenylenediamine (3), were synthesized and characterized by elemental analysis, Fourier transform infrared (FT-IR), UV-Visible (UV-Vis) and electron paramagnetic resonance (EPR) spectroscopies. The results from the 4-nitrophenol reduction showed that 3 has the highest catalytic activities with 97.5% conversion, followed by 2 and 1 with 95.2% and 90.8% conversions, respectively. The optimization of the catalyst amount revealed that 1.0 mol% of the catalyst was the most optimized amount with the highest conversion compared to the other doses, 0.5 mol% and 1.5 mol%. Recyclability and reproducibility tests confirmed that all three complexes were active, efficient, and possess excellent reproducibility with consistent catalytic performances and could be used again without a major decrease in the catalytic activity.     

α,α-二乙酰基二苄硫缩烯酮的碱催化脱乙酰基反应及缩合反应机理研究

α-羰基二硫缩烯酮是一类极其重要的有机合成中间体，烷硫基对该类具有推-拉电子效应的共轭体系的性质影响很大。据此，我们率先提出了烷硫基对α-羰基二硫缩烯酮类化合物的化学行为具有调控作用的观点，并将其归因于空间电子因素的作用，α-乙酰基-α′-羰基二苄硫缩烯酮(1)具有多反应性特征。近来，我们利用该特征在氢氧化钠催化下通过化合物1的环合合成了多取代噻吩类化合物；在乙醇钠-醋酸铅作用下经乙氧基对化合物1的苄硫基的取代实现了α-羰基-O，O-缩烯酮的合成。     

An investigation of condensed heteroaromatic systems including a thiophene ring

The influence of the temperature, of the natures of the initiator and of the initial compound, and of the concentrations of the reactants on the process and nature of the transformations of 2- and 3-alkyl-, 2- and 3-formyl-, and 2- and 3-hydroxymethylbenzo[b]thiophenes under conditions of liquid-phase oxidation with oxygen in the presence of cobalt acetate in acetic acid has been studied. According to their relative ease of oxidation, the homologs and derivatives of benzo[b]thiophene, thiophene, and benzene can be arranged in the following sequence: 3-methylbenzo[b]thiophene > 2-methylbenzo[b]thiophene > 2-methylthiophene > toluene > 3-methylbenzo[b]thiophene dioxide > 2-methylbenzo[b]thiophene dioxide; benzaldehyde > benzo[b]thiophene-3-carbaldehyde > thiophene-2-carbaldehyde > benzo[b]-thiophene-2-carbaldehyde; 3-hydroxymethylbenzo[b]thiophene > 2-hydroxymethylbenzo[b]-thiophene > benzyl alcohol > 2-hydroxymethylthiophene. The liquid-phase oxidation of alkyl-substituted benzo[b]thiophenes can be used to obtain aldehydes, ketones, and acids of the benzo[b]thiophene series.For Communication XXIV, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1026–1033, August, 1973.     

Ambident chemosensors based on benzo[<Emphasis Type="Italic">h</Emphasis>]chromen-2-one

Schiff bases derived from 7-hydroxy-4-methyl-2-oxobenzo[h]chromene-8-carbaldehyde in solution exist as equilibrium mixtures of benzoid and quinoid tautomers. The fraction of the quinoid tautomer increases with rise in solvent polarity. The Schiff base containing a benzo-15-crown-5 fragment on the nitrogen atom was shown to be a new ambident chemosensor capable of selectively binding transition metal cations via reaction at the o-hydroxyaldehyde imine fragment and alkaline-earth metals via host-guest interaction with the crown ether moiety. This compound exhibits a pronounced sensor activity toward Mg²⁺ and Ba²⁺ ions and is a selective naked-eye fluorescent chemosensor for Cu²⁺ and Co²⁺ ions.     

Syntheses of Some New Group 4 non-Cp Complexes Bearing Schiff-base, Thiophene Diamide Ligands Respectively and Their Catalytic Activities for a-Olefin Polymerization

Totally sixteen new titanium and zirconium non-Cp complexes supported by Schiff-base, or thiophene diamide ligands have been synthesized. The complexes are obtained by the reaction of M(OPr-i)4(M=Ti,Zr) with the corresponding Schiff-base ligand in 1:1 molar ratio in good yield. The thiophene diamide titanium complex has been prepared from trimethylsilyl amine [N,S,N] ligand and TiCl4 in toluene at 120℃. All complexes are well charac-terized by ^1H NMR, IR, MS and elemental analysis. When activated by excess methylaluminoxane (MAO), complexes show moderate catalytic activity for ethylene polymerization, and complex If (R^1=CH3,R^2=Br) exhibits the highest activity for ethylene and styrene polymerization. When the complexes were preactivated by triethylaluminum (TEA), both polymerization activities and syndiotacticity of the polymers were greatly improved.     

Zur photochemie des β-pyridinalanilins

The Schiff base, 3-pyridinal aniline was cyclized via photohydration into quinoline-3-carbaldehyde in 20% yield.     

Synthesis and spectroscopic studies of homo-binuclear, alkoxo bridged homo- and hetero-tetranuclear metal complexes of a bis-N2O4 Schiff base ligand derived from ethanolamine and macroacyclic tetranaphthaldehyde

Three new homo-binuclear Ni(II), Cu(II), Zn(II) complexes (2-4), homo-tetranuclear Cu(II) complex (5), and hetero-tetranuclear Cu(II)-Ni(II) complex (6) of a macroacyclic potentially bis-hexadentate N2O4 Schiff base have been synthesized. The imino-alcohol ligand, H4L was obtained by the condensation of ethanolamine with 2,2'-[2,3-bis(1-formyl-2-naphthyloxymethyl)-but-2-ene-1,4-diyldioxy]bis(naphthalene-1-carbaldehyde). The structures of both the Schiff base and its complexes have been proposed by elemental analyses, spectroscopic data i.e. IR, 1H and 13C NMR, UV-vis, electrospray ionisation mass spectra, molar conductivities and magnetic susceptibility measurements. The ligand has two similar compartments to bind first primary two metal ions, and acts bi- or tetra-negative, bis-tetradentate forming five membered chelate ring. However, secondary two metal ions (either Cu2+ or Ni2+) are ligated with dianionic oxygen atoms of the alcohol groups and are linked to the 1,10-phenanthroline-nitrogen atoms in the tetranuclear complexes (5 and 6).     

Bimetallic complexes of Schiff base bis-[4-hydroxycuomarin-3-yl]-1N,5N-thiocarbohydrazone as a potentially dibasic pentadentate ligand. Synthesis, spectral, and antimicrobial properties

The Schiff base bis-[4-hydroxycuomarin-3-yl]-¹N,⁵N-thiocarbohydrazone, H²L, was prepared by the reaction of 4-hydroxycoumarine-3-carbaldehyde with thiocabohydrazide in 2:1 molar ratio. The ligand and its binuclear complexes with Cu(II), Ni(II), Zn(II), Co(II), Mn(II), Fe(III) and Cr(III) ions were characterized via elemental analysis, ¹H NMR, mass spectrometry, infrared, and electronic spectra, as well as room temperature magnetic susceptibilities. Furthermore, the thermal stabilities of two representative complexes were also investigated. The Schiff base and its metal complexes were screened for their antifungal and antibacterial activities against different species of pathogenic fungi and bacteria and their biopotency have been discussed.     

5-(2-Thienylsulfanyl)thiophene-2-carbaldehyde: Thioacetalization,chloromethylation, and oxidation

5-(2-Thienylsulfanyl)thiophene-2-carbaldehyde reacted with propane-1-thiol and propane-1,3-dithiol in the presence of chloro(trimethyl)silane to give previously unknown 5-[bis(propylsulfanyl)methyl]-2-(2-thienylsulfanyl)thiophene and 2-[5-(2-thienylsulfanyl)thiophen-2-yl]-1,3-dithiane. Chloromethylation of 5-(2-thienylsulfanyl)thiophene-2-carbaldehyde with formaldehyde in a stream of hydrogen chloride in the presence of zinc chloride resulted in the formation of an oligomeric product consisting of thiophene rings connected alternately by sulfur and methylene bridges. The oligomer is formed via fast polycondensation of the primary chloromethylation product with the initial aldehyde. 5-(2-Thienylsulfanyl)thiophene-2-carbaldehyde was oxidized at the sulfide and aldehyde groups with 30% hydrogen peroxide in glacial acetic to produce 5-(2-thienylsulfonyl)thiophene-2-carboxylic acid.