基于邻香草醛缩2-氨基-4-硝基苯酚的Schiff碱有机锡配合物的合成、晶体结构及生物活性

邻香草醛缩2-氨基4-硝基苯酚(H₂L)分别与二丁基氧化锡、二苄基二氯化锡反应, 合成了二丁基锡Schiff碱配合物(1)和单苄基Schiff碱配合物(2)。配合物经元素分析、¹H NMR、¹³C NMR、IR、UV-Vis表征, 并用X-射线单晶衍射测定了分子结构。研究了配体H₂L及配合物1、2对癌细胞Hela、MCF7、HepG2、Colo205、NCI-H460的抑制活性, 结果表明配合物1对这5种癌细胞的抑制效果优于现有抗癌药物卡铂, 可作为抗癌药物的候选化合物。在Tris缓冲溶液中, 以EB做为荧光探针, 用荧光光谱法研究了配体H₂L及配合物2与鲱鱼精DNA的相互作用, 结果表明配合物与DNA作用主要是由于Schiff碱配体协同效应所致。     

镍(Ⅱ)和铜(Ⅱ)Schiff碱配合物的合成及其晶体结构

合成了2个Schiff碱配体:双(溴代乙酰丙酮)缩乙二胺[表示为H₂(3-Br-acacen)]和二(溴代乙酰丙酮)缩-1，2丙二胺[表示为H₂(3-Br-acacpen)]，Schiff碱配体与醋酸镍或醋酸铜作用分别得到相应的4个Schiff 碱金属配合物:Ni^Ⅱ(3-Br-acacen) (1)、Cu^Ⅱ(3-Br-acacen) (2)、Ni^Ⅱ(3-Br-acacpen) (3)和Cu^Ⅱ(3-Br-acacpen) (4)。用FTIR和元素分析对配合物进行表征，并用X-射线单晶衍射测定了4个配合物的晶体结构。配合物1 和2 的分子基本为一平面结构，3和4则是非平面分子结构。     

基于席夫碱配体构筑的Ln2Ⅲ配合物的结构、荧光性质及生物活性

以多齿席夫碱配体 H₂L(H₂L=(E)-N′-(3-乙氧基-2-羟基亚苄基)-3-羟基吡啶甲酰肼)为配体,与 Ln(acac)₃·2 H₂O(Ln=Tb、Ho、Er;acac^-=乙酰丙酮根)反应,通过溶剂热法,成功得到了 3例新的双核稀土配合物[Ln₂(acac)₂(L)₂(C₂H₅OH)₂](Ln=Tb (1)、Ho(2)、Er(3))。单晶X射线衍射分析表明：配合物1~3的结构主要由2个Ln^Ⅲ离子、2个乙酰丙酮根(acac^-)、2个L^2-及2个C₂H₅OH组成,中心Ln^Ⅲ离子通过2个μ₂-O原子相互连接,形成一个平行四边形的Ln₂O₂核心。固体荧光实验测试结果表明：配合物1在室温下表现出Tb^Ⅲ离子的荧光特征发射峰。此外,生物活性研究表明,与配体H₂L和稀土离子相比较,配合物1~3具有更强的抗菌活性。采用紫外光谱法、循环伏安法、凝胶电泳法和荧光光谱法研究了配合物 1~3与小牛胸腺 DNA之间的相互作用,结果表明配合物主要以插入作用的方式与小牛胸腺DNA结合。     

镉(Ⅱ)、锌(Ⅱ)与2-乙酰吡啶缩邻氨基苯甲酰腙配合物合成及晶体结构

采用Schiff碱配体2-乙酰吡啶缩邻氨基苯甲酰腙(L)分别与Cd(NO₃)₂·4H₂O和Zn(CH₃COO)₂·2H₂O进行配位反应,得到2个配合物[CdL(NO₃)₂·H₂O](1)和[ZnL₂](2).分别采用¹H NMR、FTIR和元素分析等手段对化合物进行了表征,并测定了2个配合物的单晶结构.结构解析表明,配合物1属于单斜晶系,P2₁/n空间群,配合物2属于单斜晶系,P2₁/c空间群.对配体和配合物的体外抑菌活性进行了初步考察,结果表明,配体L和配合物1具有一定的抑菌活性.     

邻香兰素缩对甲苯胺Schiff碱过渡金属配合物的合成、表征、晶体结构及抗菌活性研究

合成了邻香兰素缩对甲苯胺Schiff碱HL(C₁₅H₁₅NO₂)与锰(Ⅱ),锌(Ⅱ)的配合物[Mn(HL)₃(CH₃OH)](ClO₄)₂ (1)和[Zn(HL)₂(H₂O)₂](ClO₄)₂ (2)。用元素分析、红外光谱、紫外-可见光谱、¹H NMR核磁共振、摩尔电导等手段进行表征;用单晶X-射线衍射方法测定了配合物的晶体结构,配合物的中心金属离子与Schiff碱配体中的酚羟基氧及甲氧基氧发生配位,锰(Ⅱ)的配位数为7,而锌(Ⅱ)的配位数为6。测定了配体和配合物对大肠杆菌、金黄色葡萄球菌、枯草杆菌的抗菌活性。     

N-(2-氧乙酸-3-甲氧基)苄叉二胺合锌(Ⅱ)配合物的合成、晶体结构及光学性质研究

本文通过修饰邻香草醛芳环上羟基的方法,得到两种Schiff碱配体:N,N'-二(2-氧乙酸-3-甲氧基)苄叉乙二胺(H₂L¹)和N,N′-二(2-氧乙酸-3-甲氧基)苄叉1,3-丙二胺(H₂L₂),利用水热合成方法以新合成的配体为基点设计合成了2个新的六配位Schiff碱锌(Ⅱ)配合物[Zn(L¹)]·7H₂O(1)和[Zn(L²)]·7H₂O(2),通过元素分析、红外光谱和核磁共振光谱等测试手段对配合物进行了表征,并用X射线单晶衍射测得Zn(Ⅱ)配合物的晶体结构。X射线晶体学研究表明两种配合物晶体结构中都包含多个溶剂水分子,配合物1是以Zn(Ⅱ)为中心扭曲的三方棱柱构型,配合物2构型是以Zn(Ⅱ)为中心扭曲的八面体构型。初步研究了两种配合物的固体发光性,结果表明这两种配合物具有良好的光致发光的性能,有望在光学材料方面得到应用。     

镍(Ⅱ)、镉(Ⅱ)与去甲基斑蝥酸钠和咪唑配合物的结构、与DNA/BSA的作用及抗增殖活性

以2种配体去甲基斑蝥酸钠(Na₂DCA=7-氧杂二环[2.2.1]庚烷-2,3-二甲酸钠)和咪唑(IM),分别与镍(Ⅱ)和镉(Ⅱ)的醋酸盐通过溶液法合成了2种配合物[Ni(IM)(DCA)(H₂O)₂]·2H₂O(1),[Cd₂(IM)₄(DCA)₂]·2H₂O(2)。应用元素分析、热重分析、红外光谱及X-射线单晶衍射法对配合物的组成和结构进行了表征。配合物1与2的中心离子分别与咪唑的亚胺氮原子、去甲基斑蝥酸根的羧基氧原子和醚键氧原子配位,配位数均为6,分别为单核(1)和双核(2)配合物。通过紫外光谱法、荧光光谱法和粘度法研究了配合物与DNA的相互作用。结果表明,配合物能通过部分插入模式与DNA发生较强的结合作用(K_b:5.51×10³(1)、1.01×10³(2)L·mol^-1)。同时,利用荧光光谱法研究了配合物与牛血清白蛋白(BSA)的相互作用。配合物能与BSA发生强烈的相互作用(K_AM:1.91×10⁵(1)和6.17×10⁵(2)L·mol^-1),结合位点数均为1。测试了配合物对人肝癌细胞(SMMC₇₇₂₁)和人乳腺癌(MCF-7)的体外抗增殖活性。结果显示,配合物对不同癌细胞具有选择性抑制作用。镍配合物(1)对SMMC₇₇₂₁的抗癌活性较去甲基斑蝥酸钠有明显提高。     

2-羰基-3-苯基丙酸芳甲酰腙二(2,4-二氯苄基)锡配合物的合成、晶体结构及生物活性

二（2,4-二氯苄基）二氯化锡分别与2-羰基-3-苯基丙酸苯甲酰腙及2-羰基-3-苯基丙酸水杨酰腙反应,合成了2个取代苄基锡配合物（C1、C2）,通过元素分析、IR、¹H NMR、¹³C NMR、¹¹⁹Sn NMR、X射线单晶衍射以及热重分析等表征了配合物结构。测试了配合物对癌细胞Hela、MCF7、HepG2、Colo205、NCI-H460以及正常人体胚肾细胞HEK293、正常人体肝细胞HL7702的体外抑制活性;在Tris-HCl缓冲溶液中,以EB做为荧光探针,用荧光光谱法初步研究了配合物与小牛胸腺DNA的相互作用。结果表明：配合物C1、C2对5种癌细胞都有明显的抑制作用,配合物C2对HEK293、HL7702的细胞毒性远小于C1;配合物C1与小牛胸腺DNA作用是插入结合与静电结合共同作用所致,配合物C2与小牛胸腺DNA作用是插入结合作用所致。     

阴离子调控的含反式-双(苯甲酰丙酮)-1,4-环己二胺银配位聚合物的合成、晶体结构及其荧光性质

将配体反式-双(苯甲酰丙酮)-1,4-环己二胺(L)与AgX(X=NO₃^-,BF₄^-,SbF₆^-,ClO₄^-)进行反应得到4个配合物{[Ag(L)]NO₃}_n(1),{[Ag(L)(H₂O)]BF₄}_n(2),{[Ag₂(L)₃](SbF₆)₂}_n(3),{[Ag(L)]ClO₄}_n(4),并用元素分析,红外和X-射线单晶衍射表征了4个配合物的结构。在固体状态下,配合物1和2都形成2D网状结构的配位聚合物,都有2个不同配位类型的配体,不同的是,配合物1中桥连配体的1,4-环己二胺1,4位的C-N键在直立键上,而配合物2中桥连配体的1,4-环己二胺中1,4位的C-N键在平伏键上;配合物3也有2种不同配位类型的配体,但是与配合物1和2不同,配合物3形成1D配位聚合物;配合物4中的配体只有一种配位类型,配合物4形成2D网状结构。4个配合物中,配合物2,3的阴离子未参与Ag(Ⅰ)配位,配合物1和1的阴离子与Ag(Ⅰ)配位。同时,研究了配体和配合物在室温下的固态荧光性质。     

基于2，5-二溴对苯二甲酸配体的锰/钴配合物的合成、晶体结构及性质

将有机物2,5-二溴对苯二甲酸(H₂L1)作为主配体,2,2′-联吡啶(L₂)、1,10-菲咯啉(L₃)分别作为辅配体,通过溶剂热法与一水硫酸锰、六水合硝酸钴分别反应得到配合物[Mn₂(L₁)₂(L₂)₂(H₂O)₂]_n (1)和[CO₂(L₁)₂(L₃)₂(H₂O)₂]_n (2)。通过单晶 X射线衍射法、荧光光谱、热重分析等测试手段对这 2种配合物进行分析研究。结果表明配合物 1是由 Mn²⁺配位连接 L₁^2-与 L₂形成无限延伸的二维网络状结构,各层在分子间氢键和π-π堆积作用下形成了三维网络状结构。配合物2是由CO²⁺配位连接L₁^2-和L₃形成的无限延伸的二维网络状结构,各层在分子间氢键和π-π堆积作用下形成三维网络状结构。且这2种配合物均具有良好的荧光性和热稳定性,配合物1和2的最大发射波长分别为355和365 nm。     

Cyclometalated complexes containing ferrocenyl Schiff base: Preparation,characterization, DFT calculations,application in cancer and biological researches and MOE studies

A series of transition metal (II/III) complexes containing organometallic Schiff base ligand (H₂L) had been synthesized and characterized by using elemental analysis (C, H, N, M), molar conductivity, IR, UV–Vis, ¹H NMR and mass spectral analysis. Also, their TG and DTG behaviors were investigated. The ligand was prepared by condensation of 4-aminosalicylic acid with 2-acetylferrocene in 1:1 M ratio. The data of elemental analysis indicated that the prepared complexes were synthesized also in a 1:1 M ratio. The ligand behaved as neutral bidentate ligand that coordinated to metal ions through protonated O-phenolic and protonated carboxylic-OH groups. All complexes had octahedral structure. DFT calculations for H₂L ligand were determined with some parameters such as HOMO-LUMO energy gab, electronegativity and chemical hardness–softness. Antimicrobial activity of both H₂L Schiff base ligand and its metal complexes was tested against different strains of bacteria and fungi species. Furthermore, all compounds had been screened for their anticancer activities against breast cancer (MCF-7) cell line. [Cu(H₂L)(H₂O)₂Cl₂]·2H₂O complex had the lowest IC₅₀ value = 47.3 µg/mL. For determining the more effective and probable binding mode between the H₂L ligand, Co(II) and Zn(II) complexes with different active sites of 4K3V, 2YLB and 3DJD receptors, so molecular docking studies were investigated.     

氨基酸席夫碱镍、钴配合物的合成、晶体结构与抑菌活性

合成了1-苯基-3-甲基-4-对氯苯甲酰基-5-吡唑啉酮缩L-苯丙氨酸甲酯Schiff碱Ni(Ⅱ)、Co(Ⅱ)配合物[NiL_2](CH_3OH)(1)和[CoL_2](CH_3OH)(2)。用元素分析、红外光谱和X-射线单晶结构进行了表征,配合物1和2的晶体结构都同时含有两个独立子单元及一个游离的甲醇分子,各子单元都形成六配位的八面体结构。采用琼脂扩散法测定了配体和配合物对大肠杆菌、金黄色葡萄球菌抗菌活性,结果表明配合物2对大肠杆菌的抑制作用最强。     

Biomolecular docking,antimicrobial and cytotoxic studies on new bidentate schiff base ligand derived metal (II) complexes

Three new metal complexes [Cu(L)₂] (1), [Co(L)₂] (2) and [Zn(L)₂] (3) have been prepared by the reaction of hydrated salts of metal (II) acetate with new Schiff base ligand HL, [2‐((4‐(dimethylamino)phenylimino)methyl)‐4,6‐di‐t‐butylphenol] and characterized by different physico‐chemical analyses such as elemental analysis, single XRD, ¹H NMR, FTIR and UV–Vis spectroscopic techniques. Their biomolecular docking, antimicrobial and cytotoxicity studies have also been demonstrated. The proposed structure of Schiff base ligand HL and complex 2 are confirmed by Single crystal X‐ray crystallography study. This analysis revealed that metal (II) complexes remain in distorted tetrahedral coordination environments. The electronic properties such as HOMO and LUMO energies are carried out by gaseous phase DFT/B3LYP calculations using Gaussian 09 program. Complex 1 showed a good binding propensity to the DNA and HSA, during the assessment of docking studies. Schiff base ligand HL and its metal (II) complexes, 1–3 screened for their in vitro antimicrobial activities using the disc diffusion method against selected microbes. Complex 1 shows higher antimicrobial activity than complexes 2, 3 and Schiff base ligand HL. According to the results obtained from the cytotoxic studies, Schiff base ligand HL and its metal (II) complexes 1–3 have better cytotoxicity against MCF‐7 cell lines with potency higher than the currently used chemotherapeutic agent cyclophosphamide.     

Synthesis,spectral, MOE and cytotoxic studies of nano Ru (III), Pr (III) and Gd (III) metal complexes with new Schiff base ligand based on dibenzoyl methane and anthranilic acid

Three metal complexes of Gd (III), Pr (III) and Ru (III) metal ions with Schiff base ligand (H₂L) (prepared through l:2 condensation of dibenzoyl methane and anthranilic acid) were prepared and characterized using various physio-chemical methods like: elemental analyses, IR, mass spectrometry, magnetic moment, ¹H NMR, SEM and TG/DTG thermal analysis. The analytical and spectroscopic tools showed that the complexes had composition of ML type with octahedral geometry. The mass spectra gave the possible molecular ion peaks of the Schiff base ligand and three metal chelates. The ¹H NMR data supported the IR finding that the ligand coordinated to the metal ions via carboxylate proton displacement. Thermal analysis (TG/DTG) was utilized to differentiate between coordinated and hydrated water molecules. The Schiff base (H₂L) and its metal complexes have been screened for their antibacterial activity against Gram (+) bacteria (Streptococcus aureus and Bacillis subtilis), Gram (−) bacteria (Salmonella typhimurium and Escherichia coli) and two fungi (Aspergillus fumigatu and Candida albicans) organisms by agar diffusion method. The anticancer activity was screened against human breast cancer cell line (MCF-7). The H₂L ligand and its metal chelates were docked using MOE 2008 software with crystal structure of Gram (+) bacteria: Staphylococcus aureus (PDB ID: 3Q8U) and Gram (−) bacteria: Salmonella typhimurium (PDB ID: lDZR) to identify the binding orientation or conformation of the complex in the active site of the protein.     

Syntheses,characterization and biological studies of zinc(II), copper(II) and cobalt(II) complexes with Schiff base ligand derived from 2‐hydroxy‐1‐naphthaldehyde and selenomethionine

Novel zinc(II), copper(II), and cobalt(II) complexes of the Schiff base derived from 2‐hydroxy‐1‐naphthaldehyde and D, L ‐selenomethionine were synthesized and characterized by elemental analysis, IR, electronic spectra, conductance measurements, magnetic measurements and powder XRD. The analytical data showed the composition of the metal complex to be ML(H₂O), where L is the Schiff base ligand and M = Co(II), Cu(II) and Zn(II). IR results confirmed the tridentate binding of the Schiff base ligand involving azomethine nitrogen, naphthol oxygen and carboxylato oxygen atoms. ¹H NMR spectral data of lithium salt of the Schiff base ligand [Li(HL)] and ZnL(H₂O) agreed with the proposed structures. The conductivity values of complexes between 12.50 and 15.45 S cm² mol^?1 in DMF suggested the presence of non‐electrolyte species. The powder XRD studies indicated that Co(II) complex is amorphous, whereas Cu(II) and Zn(II) complexes are crystalline. The results of antibacterial and antifungal screening studies indicated that Li(HL) and its metal complexes are active, but CuL(H₂O) is most active among them. Copyright © 2010 John Wiley & Sons, Ltd.     

Synthesis,crystal structure,and antimicrobial activity of a series of cobalt(III) Schiff base complexes

Abstract

A series of six new mononuclear Schiff base complexes, 1–6 of cobalt(III) of the general formula, [CoLX] or its adduct with methanol, is reported. The pentadentate Schiff base ligand (H₂L) was obtained by the condensation of N-(3-aminopropyl)-N-methylpropane-1,3-diamine with 1-(2-hydroxyphenyl)ethanone (H₂L¹) or 1-(2-hydroxyphenyl)propan-1-one (H₂L²). X stands for the pseudohalides, N₃^–, N(CN)₂^? , and NCS^–. The complexes have been synthesized by the reaction of equimolar amounts of cobalt(II) nitrate with H₂L¹ or H₂L² in the presence of the respective pseudohalide in methanol medium. All the complexes have been characterized by microanalytical, spectroscopic, single crystal XRD (except 3), and other physicochemical studies. Structural studies reveal that the central Co(III) ion in 1, 2, 4, 5, and 6 adopts a distorted octahedral geometry with a CoN₄O₂ chromophore. Weak intermolecular H-bonding and/or π-interactions are operative in these complexes to bind the molecular units. The antimicrobial activity of all the complexes and their constituent Schiff bases has been tested against some common bacteria and fungi.     

Novel Schiff base ligand and its metal complexes with some transition elements. Synthesis,spectroscopic, thermal analysis,antimicrobial and in vitro anticancer activity

A novel Schiff base ligand (H₂L) was prepared through condensation of 2,6‐diaminopyridine and o‐benzoylbenzoic acid in a 1:2 ratio. This Schiff base ligand was characterized using elemental and spectroscopic analyses. A new series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) metal complexes of H₂L were prepared and characterized using elemental analysis, spectroscopy (¹H NMR, mass, UV–visible, Fourier transform infrared, electron spin resonance), magnetic susceptibility, molar conductivity, X‐ray powder diffraction and thermal analysis. The complexes are found to have trigonal bipyramidal geometry except Cr(III), Mn(II) and Fe(III) complexes which have octahedral geometry based on magnetic moment and solid reflectance measurements. The infrared spectral studies reveal that H₂L behaves as a neutral bidentate ligand and coordinates to the metal ions via the two azomethine nitrogens. ¹H NMR spectra confirm the non‐involvement of the carboxylic COOH proton in complex formation. The presence of water molecules in all reported complexes is supported by thermogravimetric studies. Kinetic and thermodynamic parameters were determined using Coats–Redfern and Horowitz–Metzger equations. The synthesized ligand and its complexes were screened for antimicrobial activities against two Gram‐positive bacteria (Bacillus subtilis and Staphylococcus aureus), two Gram‐negative bacteria (Escherichia coli and Neisseria gonorrhoeae) and one fungus (Candida albicans). Anticancer activities of the ligand and its metal complexes against human breast cancer cell line (MCF7) were investigated. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis,characterization, semi-empirical study and biological activities of homobimetallic complexes of tranexamic acid with organotin(IV)

The Schiff base has been synthesized by reacting tranexamic acid with indol-3-carboxyaldehyde in the first step and then with carbon disulfide at room temperature in the second step. The homobimetallic complexes have been synthesized by reaction of Schiff base with R₂SnCl₂ and R₃SnCl in 1?:?2?M ratio under stirring, where R?=?methyl, n-butyl and phenyl. The ligand and complexes have been characterized by elemental analysis, FT-IR, multinuclear NMR (¹H, ¹³C and ¹¹⁹Sn) and semi-empirical study. IR data reveal the bidentate nature of the ligand. Five- or six-coordinate geometry was confirmed in solution by NMR spectroscopy. The homobimetallic complexes and ligand were tested in vitro against some pathogenic bacteria and fungi to assess their antimicrobial properties. The complexes show biological activities with few exceptions.     

Spectroscopic,thermal, biological activity,molecular docking and density functional theoretical investigation of novel bis Schiff base complexes

New Schiff base ligand (H₂L, 1,2‐bis[(2‐(2‐hydroxyphenylimino)‐methyl)phenoxy]ethane) came from condensation reaction of bisaldehyde and 2‐aminophenol was synthesized in a molar ratio 1:2. Metal complexes and the ligand were completely discussed with spectroscopic and theoretical mechanism. The complexes with Fe(III), Cr(III), Mn(II), Co(II), Cu(II), Ni(II), Th(IV) and Zn(II) have been discussed and characterized by elemental analyses, molar conductance, IR, mass spectroscopy, thermal, magnetic measurements, and ¹H NMR. The results proved that the Schiff base was a divalent anion with hexadentate O₄N₂ donors came from the etheric oxygens (O1, O2), azomethine nitrogens (N1, N2) and deprotonated phenolic oxygens (O3, O4). Density Functional Theory using (B3LYP/6‐31G*) level of theory were implemented to predict molecular geometry, Mulliken atomic energetic and charges of the ligand and complexes. The calculation display that complexes had weak field ligand. The binding energy ranged from 650.5 to 1499.0 kcal/mol for Mn(II) and Th(IV) complexes, respectively. The biological behavior of the Schiff base ligand and its metal complexes were displayed against bacteria and fungi organisms. Fe(III) complex gave remarkable biological activity in comparison with the parent bis Schiff base.