PMBP与氯代苯胺的缩合反应和抑菌活性

报道了1-苯基-3-甲基-4-苯甲酰基-吡唑啉-5-酮(PMBP)与邻、间、对氯苯胺和2,4-二氯苯胺发生缩合反应生成的席夫碱配体及其配合物的合成和结构表征.利用量子化学计算方法讨论了该缩合反应的机理.抑菌活性测定结果表明化合物对金黄色葡萄球菌和大肠杆菌均有一定的抑菌活性,其中以钴配合物的抑菌活性最好.     

PMBP缩2-萘胺席夫碱及其铜(Ⅱ)配合物的合成与抑菌活性

合成了1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5(PMBP)缩2-萘胺席夫碱(HL)及其铜(Ⅱ)配合物,由元素分析、络合滴定法、质谱和摩尔电导值确定配合物的组成为[CuL2],通过核磁共振氢谱、红外光谱、热重谱和液相色谱-质谱联用技术对配体和配合物的结构进行了表征,同时还对目标化合物的抑菌活性进行了初步考察。结果表明:配体和配合物对受试的4个菌种均有不同程度的抑菌活性,抑菌能力配合物强于配体,呈现浓度效应,在浓度为3.0 mg.mL-1时最大直径可达14.9 mm。     

1-对氯苯基-3-苯基-4-苯甲酰基-吡唑啉酮-5缩胺类席夫碱铜配合物的合成与抑菌活性

合成了7种新型酰基吡唑啉酮席夫碱过渡金属铜配合物.7种席夫碱分别为:1-对氯苯基-3-苯基-4-苯甲酰基-吡唑啉酮-5缩苯胺(HS1)、对氯苯胺(HS2)、对溴苯胺(HS3)、糠胺(HS4)、对甲氧苯胺(HS5)、对乙氧苯胺(HS6)和萘胺(HS7)席夫碱.由元素分析、络合滴定法、质谱和摩尔电导值确定配合物的组成通式为[Cu(S)2](S=S1,S2,S3,S4,S5,S6,S7),通过红外光谱、热重谱、核磁共振氢谱和液相色谱-质谱联用技术对配体及配合物的结构进行了表征,同时对7个席夫碱配体及其7个铜配合物的抑菌活性进行了初步研究.表征结果表明:在不同的测试条件下,7个配体的异构体存在方式不同.配位时酮式结构可能转化为烯醇式结构,按去质子方式以烯醇氧负离子和亚胺基氮原子双齿形式与铜中心离子成键.抑菌实验结果显示:所有化合物对受试的4个菌种均有不同程度的抑菌活性,其中配合物普遍强于配体.抑菌能力呈现浓度效应,在浓度为3.0mg·mL-1时最大直径可达16.0mm.     

基于Schiff碱及咪唑类配体的镍(Ⅱ)配合物的合成、结构及其抑菌活性研究

以三齿席夫碱配体H2L{1-苯基-3-[(2-羟基苯)亚胺]-1-丁酮}和单齿N-杂环[咪唑(Himdz),2-甲基咪唑(Mimdz)]与Ni(OAc)2·4H2O进行配位反应,得到2个配合物[Ni(L)(Himdz)](1),[Ni(L)(Mimdz)](2)。并用元素分析,FTIR和X-射线单晶衍射进行了表征。在固体状态,配合物1和2都属于单斜晶系,P21/c空间群,分子间通过C-H…π相互作用形成二聚体,二聚体中的每个分子通过N-H…O氢键向空间扩展成一维锯齿链状结构。初步研究了配体和配合物的体外抑菌活性,结果表明,配合物1和2具有一定的抑菌活性。     

N-（5-氯-2-羟基苄基）氨基酸衍生物及其金属配合物的合成、表征及抑菌活性

以N-（5-氯-2-羟基苄基）氨基酸及其酯为配体,在室温下以水和甲醇为溶剂,采用分步法,以1∶1的摩尔比将配体与金属离子在弱碱性条件下混合,合成了20种未见报道的N-(5-氯-2-羟基苄基)氨基酸类金属配合物。 用核磁、红外和紫外光谱技术对其结构进行了表征。 证明在配合物中配体N-(5-氯-2-羟基苄基)氨基酸的羟基、胺基和羧基均参与了配位。 抑菌测试表明,N-(5-氯-2-羟基苄基)氨基酸类金属配合物的抑菌活性普遍高于其配体,尤其对白色念珠菌的抑菌效果更为明显,均高达100%。 对N-（5-氯-2-羟基苄基）席夫碱氨基酸酯的合成方法进行了优化,得到了较佳的合成工艺条件。     

1-甲基-2-咪唑醛缩甘氨酸Schiff碱配合物的合成与抑菌活性

以1-甲基-2-咪唑醛和甘氨酸缩合的Schiff碱为配体,合成了4种新的过渡金属配合物[M(C7N3H8O2)(H2O)n]Cl O4(M=Co,Ni,Cu,Zn).经元素分析、摩尔电导率测定、红外光谱、电子光谱和热重分析确证配合物的组成和结构.初步抑菌活性实验表明,合成的配合物对多种菌株有明显的抑菌活性.     

1-甲基-2-咪唑醛缩乙醇胺Schiff碱配合物的合成与抑菌活性

以1-甲基-2-咪唑醛和乙醇胺缩合的Schiff碱为配体,合成了四种新的过渡金属配合物[M(C7N3H11O)2](ClO4)2(M=Co,Ni,Cu,Zn),并通过元素分析、摩尔电导率的测定、红外光谱和电子光谱确证其组成和结构。初步抑菌实验表明,四种配合物均对多种菌株有明显的抑菌活性。     

基于季戊四胺席夫碱的Ni(Ⅱ)和Cu(Ⅱ)配合物的合成、结构及其抑菌活性

以4-甲氧基水杨醛和季戊四胺进行缩合反应得到席夫碱化合物H_4L,然后将配体H_4L分别与Ni(Cl O_4)_2·6H_2O、Cu(Cl O_4)_2在乙醇溶液中进行配位反应,得到2个席夫碱配合物[Ni_2(L)]·DMF(1)和[Cu_4(L)_2(DMSO)_3]·2DMSO(2)。并用元素分析、FT-IR和X射线单晶衍射进行了表征。配合物1和2都属于三斜晶系,P1空间群,配合物1和2都为双核配合物。初步研究了配体和配合物的体外抑菌活性,结果表明,配体及其配合物1和2对金黄色葡萄球菌具有一定的抑菌活性。     

吸电子基团对席夫碱及其钯配合在抑菌及催化活性方面的影响

报道了2, 6-二异丙基苯胺缩苯甲醛或2, 4-二氯苯甲醛席夫碱(L1和L2)及其钯配合物(1和2)的合成, 并通过元素分析、红外光谱、X-射线单晶衍射等方法对席夫碱配体及配合物进行了表征。通过与已报道的席夫碱L1及其钯配合物1结构相比较, 发现引入吸电子取代基合成的一个新的席夫碱及其钯配合(L2和2)对抑菌及催化活性有较大影响。抑菌活性试验表明, 配体及配合物均具有良好的抑菌活性, 配合物相对于配体具有更好的抑菌效果, 配体苯环上的吸电子取代基能有效提高抑菌活性。研究了两组配合物(1和2)对溴代苯和丙烯酸Heck交叉偶联生成苯丙烯酸的催化性能, 考察了不同反应因素(缚酸剂种类、反应温度及溶剂)对该反应的影响, 确定了反应的最佳条件;催化实验结果显示吸电子基团的引入增加了钯配合物的空间位阻效应进而降低其催化活性。     

吸电子基团对席夫碱及其钯配合物在抑菌及催化活性方面的影响

报道了2,6-二异丙基苯胺缩苯甲醛或2,4-二氯苯甲醛席夫碱(L1和L2)及其钯配合物(1和2)的合成,并通过元素分析、红外光谱、X-射线单晶衍射等方法对席夫碱配体及配合物进行了表征。通过与已报道的席夫碱L1及其钯配合物1结构相比较,发现引入吸电子取代基合成的一个新的席夫碱及其钯配合物(L2和2)对抑菌及催化活性有较大影响。抑菌活性试验表明,配体及配合物均具有良好的抑菌活性,配合物相对于配体具有更好的抑菌效果,配体苯环上的吸电子取代基能有效提高抑菌活性。研究了两组配合物(1和2)对溴代苯和丙烯酸Heck交叉偶联生成苯丙烯酸的催化性能,考察了不同反应因素(缚酸剂种类、反应温度及溶剂)对该反应的影响,确定了反应的最佳条件;催化实验结果显示吸电子基团的引入增加了钯配合物的空间位阻效应进而降低其催化活性。     

Synthesis, characterization, spectroscopic and thermodynamic studies of charge transfer interaction of a new water-soluble cobalt(II) Schiff base complex with imidazole derivatives

The water-soluble cobalt(II) tetradentate Schiff base complex [Co(II)L](ClO4)(2), L: (N,N'-bis(5-[(triphenylphosphonium)-methyl]salicylidine)-o-phenylenediamineperchlorate has been synthesized and characterized. This complex forms charge transfer (CT) complexes with imidazole and 1-methylimidazole. The formation constant, molar absorptivity (epsilon'), and thermodynamic parameters for charge transfer complexes formation of cobalt(II) Schiff base complexes with imidazole derivatives were determined by using UV-vis spectrophotometric method in aqueous solutions at constant ionic strength (I=0.2mol dm(-3) KNO3) at pH 6.0 and various temperatures between 292 and 315K.     

Spectroscopic and theoretical studies on axial coordination of bis(pyrrol-2-ylmethyleneamine)phenyl complexes

Metal (M=Zn(II), Ni(II), Cu(II)) complexes with tetradentate Schiff base ligand, bis(pyrrol-2-ylmethyleneamine)phenyl, has been synthesized and characterized by elemental analyses, (1)H NMR, mass spectra and UV-vis spectra. The standard association constants (K(theta)) and the thermodynamic parameters (Delta(r)H(m)(theta),Delta(r)S(m)(theta),Delta(r)G(m)(theta)) for axial coordination of imidazole derivatives with these Shiff base complexes were measured with UV-vis spectrophotometric titration. The decrease of enthalpy is found to be the drive of the axial coordination. Our Schiff base complexes can incorporate two axial ligands, except 2-Et-4-MeIm with two big substituents of great steric bulk according to stoichiometry of 1:1. ZnL displays high selectively binding to imidazole due to the steric bulk effect. Supporting density functional theory (DFT) calculations have been undertaken on B3LYP/6-31G(d) level.     

Rearrangement of manganese(III) complexes with asymmetrical N3O and N2O2 Schiff bases

Mn^III complexes of asymmetric tetradentate Schiff bases, derived from HAE (7-amino-4-methyl-5-aza-3-hepten-2-one) and aldehydes or ketones containing imidazole, pyrazine or dehydroacetic fragments, have been prepared and thoroughly characterised by elemental analysis, i.r. and electronic spectroscopy, mass spectrometry and by magnetic measurements. The X-ray crystal structure of [Mn(dha)₂(H₂O)₂] (Hdha = dehydroacetic acid), obtained by rearrangement of the corresponding asymmetrical Schiff base complex, is also reported.     

Synthesis,Characterization, and Crystal Structure of Mononuclear and Dinuclear Dioxomolybdenum(VI) Complexes with Tridentate Schiff‐base Ligands. Part 2

Mononuclear [MoO₂LD], and dinuclear [MoO₂L]₂ or [MoO₂L]₂ · D dixomolybdenum(VI) complexes have been prepared by the reaction of tridentate Schiff‐base ligands L with [MoO₂(acac)₂]. The Schiff‐base ligands have been synthesized from salicylaldehyde ( 1 , 1a , 1c , 1d ), 2‐hydroxy‐1‐naphthaldehyde ( 2 , 2c ) and 2‐hydroxy‐3‐methoxybenzaldehyde ( 3a , 3b , 3c , 3d , 3e ) with 2‐amino‐p‐cresol. All prepared complexes consist of cis‐MoO₂²⁺core coordinated by Schiff‐base ligand through two deprotonated hydroxyl groups and one imino nitrogen atom. The usual octahedral coordination around the molybdenum atoms is completed by the neutral ligand D (methanol, ethanol, dimethyl sulfoxide, imidazole or 4, 4′‐bipyridine). All compounds were characterized by elemental analyses, IR spectroscopy and some of them by X‐ray crystallography ( 1a , 2c , 3a , 3b , 3c and 3e ).     

An unexpected chelate conformation in trans‐[(R)‐N,N′‐bis(α‐phenyl­salicyl­idene)­propane‐1,2‐diaminato(2–)]­bis(1‐methyl‐1H‐imidazole‐κN3)­cobalt(III) perchlorate

The title compound, [Co(C₂₉H₂₄N₂O₂)(C₄H₆N₂)₂]ClO₄, contains an optically active tetradentate Schiff base ligand in an equatorial plane and two 1‐methyl­imidazole ligands at apical positions. The central N—C—C—N chelate ring of the Schiff base ligand has an envelope structure with a λ conformation, which is different from the solution structure predicted from circular dichroism and ¹H NMR spectra.     

Synthesis and characterization of azo-linked Schiff bases and their nickel(II), copper(II), and zinc(II) complexes

Azo compounds were prepared by coupling of benzenediazonium chloride ions with 1-amino-2-hydroxy-4-naphthalene sulfonic acid under alkaline conditions, and Schiff bases, L_1–3 were then obtained by the condensation of 1-amino-2-hydroxy-3-(phenylazo)-4-naphthalene sulfonic acid, 1-amino-2-hydroxy-3-(4-ethylphenylazo)-4-naphthalene sulfonic acid, and 1-amino-2-hydroxy-3-(4-nitrophenylazo)-4-naphthalene sulfonic acid with salicylaldehyde. New copper(II), nickel(II), and zinc(II) complexes of the Schiff base ligands were also prepared and characterized by spectroscopic methods, magnetic measurements, elemental, and thermogravimetric analysis.     

cis-Dioxo(N-salicylidene-2-aminophenolato)(imidazole)-molybdenum(VI) complexes

Summary cis-Dioxo(N-salicylidene-2-aminophenolato) (imidazole)-molybdenum(VI) complexes, [MoO₂(Sap)(Im)], (Im = imidazole or its derivatives, sap = salicylidene-2-aminophenolate) are prepared by the ligand substitution of [MoO₂(Sap)(EtOH)] with a unidentate imidazole ligand. All complexes are red or yellow, diamagnetic, non-electrolytes and possess an octahedral stereochemistry. The i.r. spectra shows two bands attributable tocis-MoO₂ stretches in addition to the vibrations of the Schiff base ligand and the imidazole derivatives. Thermal degradation of the complexes result in successive loss of imidazole ligand followed by the Schiff base, with ultimate formation of MoO₃ atca. 500 °C.     

New 5-bromo-2-hydroxybenzaldehyde S-ethylisothiosemicarbazone and its mixed-ligand Cu(II) complex with imidazole: synthesis, characterization and DFT calculation

A new Schiff base ligand of 5-bromo-2-hydroxybenzaldehyde S-ethyl-isothiosemicarbazone (H₂L) was synthesized and its mixed-ligand Cu(II) complex was also prepared by reaction of Cu(NO₃)₂·3H₂O with H₂L and imidazole. Their structures were fully characterized by elemental analysis, FT-IR, molar conductivity and UV-Vis methods. The analytical data suggest that the metal, H₂L and imidazole ratios in the Schiff base complex are 1:1:1. Single crystal diffraction was also used to better understand the molecular structure of the Cu(II) complex. The results of physico-chemical analyses of the Schiff base complex reveal the coordination geometry around the central atom is square planar. The H₂L ligand (NNO donor) is coordinated to the metal center as a tridentate bionegatively agent. Another position of the square planar geometry is occupied by the imidazole ligand. Furthermore, computational studies of the new complex were performed by carrying out DFT calculations. Geometry optimization and natural band analysis of the complex is discussed in further detail.      

Transition metal complexes of the Schiff bases derived from S-alkyldithiocarbazate with 2-pyridinecarboxaldehyde N-oxide—I. Synthesis, properties and structure of four-coordinate copper(II) complexes

Two new Schiff bases (SMPDH and SBPDH) of S-methyl- and S-benzyl-dithiocarbazate with 2-pyridinecarboxaldehyde N-oxide were prepared and confirmed by elemental analyses and IR spectra. Four copper(II) complexes of the above two Schiff base ligands with imidazole and pyridine were obtained and characterized spectroscopically. The crystal structure of [Cu(SMPD)ImH]ClO₄ was determined by X-ray diffraction analysis. The geometry of the copper atoms in these complexes is square planar with an unsymmetrical environment.     

丙二胺缩乙酰丙酮单席夫碱、咪唑金属配合物的XPS与电子结构分析

对6个丙二胺缩乙酰丙酮单席夫碱、咪唑（苯并咪唑）金属配合物进行了XPS分析，得到了配合物在生成过程中金属离子M(Cu^2 、Ni^2 、Co^2 ）的2p轨道、配位体N原子的1s轨道能级的变化道；观察到咪唑或苯并咪唑配位后，其环上另一个非配位的胺N原子向亚胺型N原子状态过渡。