Structural designing,spectral and computational studies of bioactive Schiff's base ligand and its transition metal complexes

Transition metal complexes of Mn(II) and Ni(II) have been synthesized with novel bioactive Schiff's base ligand. Schiff's base ligand i.e. benzoylacetone‐bis(2‐amino‐4‐methylbenzothioazole) has been synthesized via condensation reaction between 2‐amino‐4‐methylbenzothioazole and benzoylacetone in 2:1 ratio, respectively. Synthesized ligand has been characterized using elemental analysis, infra‐red, ¹H–NMR and mass spectroscopy techniques. Characterization of complexes was based on magnetic moment, molar conductance, elemental analysis, electronic spectra, infra‐red and EPR spectroscopic techniques. Molar conductance data suggest that metal complexes are non‐electrolytic in nature. Therefore, these complexes are formulated as [M(L)X₂], where M = Mn(II), Ni(II), L = Schiff's base ligand, X = Cl^?, CH₃COO^?, NO₃^?. Data of characterization study suggest octahedral geometry for Mn(II) and Ni(II) complexes. Geometry of metal complexes was also optimized with the help of computational study i.e. molecular modelling. Computational study also suggests octahedral geometry for complexes. Free ligand as well as its all metal complexes have been screened against the growth of pathogenic bacteria (E.coli, S.aureus) and fungi (C.albicans, C.krusei, C.parapsilosis, C.tropicalis) to assess their inhibition potential. The inhibition data revealed that metal complexes exhibit higher inhibition potential against the growth of bacteria and fungi microorganisms than free ligand.     

New Transition and Actinide Metal Complexes of 2‐Carboxy‐phenylhydrazo‐Benzoylacetone Ligand: Synthesis,Characterization and Biological Study

A new series of binary mononuclear complexes were prepared from the reaction of the hydrazone ligand, 2-carboxyphenylhydrazo-benzoylacetone (H2L), with the metal ions, Cd(II), Cu(II), Ni(II), Co(II), Th(IV) and UO2(VI). The binary Cu(II) complex of H2L was reacted with the ligands 1,10-phenanthroline or 2-aminopyridine to form mixed-ligand complexes. The binary complexes of Cu(II) and Ni(II) are suggested to have octahedral configurations. The Cd(II) and Co(II) complexes are suggested to have tetrahedral and/or square-planar geometries, respectively. The Th(IV) and UO2(VI) complexes are suggested to have octahedral and dodecahedral geometries, respectively. The mixed-ligand complexes have octahedral configurations. The structures of all complexes and the corresponding thermal products were elucidated by elemental analyses, conductance, IR and electronic absorption spectra, magnetic moments, 1H NMR and TG-DSC measurements as well as by mass spectroscopy. The ligand and some of the metal complexes were found to activate the enzyme pectinlyase.     

Synthesis of 6-acylpyrido[2,3-<Emphasis Type="Italic">d</Emphasis>]pyrimidine derivatives from 5-acetyl-4-aminopyrimidine hydrochlorides

Reaction of 2,6-disubstituted 5-acetyl-4-aminopyrimidine hydrochlorides with acetylacetone or benzoylacetone afforded new substituted 6-acylpyrido[2,3-d]pyrimidines. The reaction of these hydrochlorides with ethyl acetoacetate also proceeds according to the classical version of the Friedländer condensation to form the corresponding pyrido[2,3-d]pyrimidine-6-carboxylic acid esters.     

Synthesis and Crystal Structure of a One-dimensional Mn（Ⅱ） Coordination Polymer with 1,3-bis（4-pyridyl）propane

A new 1D zigzag chain coordination polymer, { [Mn（bpp）（bac）2]·（CHaCN）}n 1 （bpp = 1,3-bis（4-pyridyl）propane, Hbac = benzoylacetone）, has been synthesized and characterized by FT-IR spectroscopy, thermal analysis and X-ray single-crystal diffraction. In the molecular structure, all Mn atoms locate in an octahedral geometry. The guest CH3CN molecules are included in the 1D channels of the 3D packing structure of 1. Crystal data： C35H35MnNaO4, Mr = 616.60, monoclinic, space group P211c, a = 17.691（4）, b = 18,955（4）, c = 9.712（6） A, β = 93.91（3）°, V = 3249.31（1） A^3, Z = 4, Dc = 1.260 g/cm^3, F（000） = 1292, 20max = 54.9°, μ = 0.447 mm^-1, the final S = 1.020, R = 0.0693 and wR = 0.1497.     

N,N'-双(苯甲酰丙酮)-1,4-丁二胺席夫碱银(I)配合物的合成及其晶体结构

以苯甲酰丙酮与1,4-丁二胺经缩合反应制得一个新的席夫碱配体——N,N'-双(苯甲酰丙酮)-1,4-丁二胺(L);L与硝酸银经配位反应合成了配合物[Ag_2(L)(NO_3)_2]_n(1),其结构经1H NMR,13C NMR,FT-IR,元素分析和X-射线单晶衍射表征。晶体结构解析表明:1(CCDC∶1 434 692)属单斜晶系,空间群P21/c,晶胞参数a=0.997 81(5)nm,b=0.778 36(4)nm,c=1.704 13(8)nm,β=106.637 0(10),V=1.261 85(11)nm3,Z=2,Dc=1.884 g·cm~(-3),R1=0.020 8,wR_2=0.054 4。1中每个银离子为扭曲四面体的配位构型,分别和相邻配体的γ-碳原子,氧原子及两个NO_3~-的氧原子配位;每个配体作为四齿配体,分别用两端的γ-碳原子,氧原子和四个银离子配位形成1D链结构,1D通过NO_3~-与银离子配位扩展形成3D网状结构。热稳定性研究结果表明:L和1的初始分解温度分别为300℃和200℃。     

两个β-二酮Co(Ⅱ)配合物[Co(β-diketonate)2(py)2]的合成和晶体结构

钴是生物学上重要的微量元素，它能在一些酶中代替锌，而不改变原来酶的活性犤１犦，钴的光谱和磁性是酶活性部位的有效探针犤２犦。钴催化剂是单活性中心催化剂犤３犦，同时又是很好的乙烯齐聚催化剂犤４，５犦。β－二酮是重要的催化剂原料，徐德民等犤６犦报道了含有β－二酮金属配合物催化剂制备间规聚苯乙烯与聚丙烯共混复合物。宓霞等犤７犦报道了含β－二酮钛非茂催化剂催化降冰片烯聚合。近年来，已报道了一些β－二酮的Co?配合物犤８～１０犦的晶体结构，本文报道两个β－二酮的Co?配合物的合成和晶体结构。１实验部分１．１配合…     

Tautomery and acid-base properties of some azoderivatives of benzoylacetone

The structural, tautomeric and acid-base properties of the new 1-phenyl-2-(2-hydroxy-3-sulfo-5-chlorophenylhydrazo)butane-1,3-dione (H₂L¹), 1-phenyl-2-(2-hydroxy-3,5-disulfophenylhydrazo)butane-1,3-dione (H₂L²), 1-phenyl-2-(2-hydroxy-3-sulfo-5-nitrophenylhydrazo)butane-1,3-dione (H₂L³) and 1-phenyl-2-(2-hydroxy-4-nitrophenylhydrazo)butane-1,3-dione (H₂L⁴) were studied using IR, ¹H and ¹³C NMR spectroscopies and potentiometry. The study reveals that H₂L^1-4 and the known 1-phenyl-2-(2-hydroxyphenylhydrazo)butane-1,3-dione (H₂L⁵) exist in solution as a mixture of Z-enol-azo-II and hydrazo-III tautomeric forms and that an increase in the solvent polarity shifts the tautomeric balance to the enol-azo form. The thermodynamic parameters of the proton dissociation in H₂L^1-5 were determined showing that this process is unspontaneous, endothermic and entropically unfavorable.     

新型含吡啶环席夫碱的合成及其晶体结构

[N,N'-(2-胺基苯基)-2,6-二甲酰亚胺]吡啶分别与苯甲酰丙酮和4-甲氧基水杨醛通过缩合反应合成了新型含吡啶环席夫碱(1a和1b),其结构经X-射线单晶衍射,1H NMR,IR和元素分析表征.1a属三斜晶系,空间群P-1,晶体参数a=11.895(4)(A),b=12.584(4)(A),c=13.191(4)...     

Mn（Ⅲ）—苯甲酰丙酮缩乙二胺—有机碱配合物的合成及结构

合成了４种锰（Ⅲ）－苯甲酰丙酮缩乙二胺－有机碱配合物：Ｍｎ（ｂｚａｃｅｎ）ＬＣｌＯ４．（Ｌ为哌嗪，吡啶，γ－甲基吡啶和乙腈）。测定了配合物［Ｍｎ（ｂｚａｃｅｎ）（ＣＨ３ＣＮ）ＣｌＯ４］的结构，晶体属正交晶系。空间群Ｐｎｍａ。晶胞参数：ａ＝０．９０７７（１），ｂ＝１．５５６３（１）ｎｍ，ｃ＝１．７２０５（２）ｎｍ，Ｖ＝２．４３０５ｎｍ＾３，Ｚ＝４，Ｄｃ＝１．４８ｇ／ｃｍ＾３，Ｄｍ＝１．４９ｇ／ｃｍ＾     

13C-CP/MAS-NMR spectroscopy of tridentate diacidic ligands and their titanium(IV) chelates. molecular structure of bis[benzoylacetone thiobenzoylhydrazonato(2-)]titanium(iv)

A series of tridentate diacidic ligands having the donor set ONO(S) as well as the corresponding titanium(IV) chelates were studied by¹³C-CP/MAS-NMR spectroscopy. Structural changes caused by the complex formation are discussed. The crystal structure of bis[benzoylacetone thiobenzo-ylhydrazonato(2-)]titanium(IV) was determined by X-ray analysis as to be distorted trigonal prismatic. Orthorhombic space group Pca2_l,Z=4, 3304 observed independent reflections, unit-cell parameters at 298 K:a=22,808(2) å,b=13,073(4) å,c=10,450(4) å.