Characterization of a Novel Curcumin based Schiff base Ligand, Synthesized by Microwave Method

A new Schiff base ligand derived from curcumin and ethylenediamine has been synthesized by the microwave irradiation method. The synthesized ligand was characterized by using FT-IR, UV-VIS, Molar conductance, NMR, PL and DLS studies. The results confirmed that the successful formation of Curcumin Based Schiff Base ligand. The ligand synthesized was stable at room temperature, completely soluble in hot methanol/DMF, partially soluble in ethanol/DMSO/acetone and insoluble in water. The spectra studies of FTIR and UV-visible confirmed the formation of the azomethine group in the ligand. NMR spectrum confirmed the presence of aromatic proton, hydroxyl proton, amine proton etc in the ligand. The luminescent property of the ligand was confirmed by the photoluminescence spectroscopic method. The low molar conductance value showed the non-electrolytic nature of the ligand. The dynamic light scattering studies showed that the ligand synthesized was in nanometer scale. The structure of the ligand was also proposed based on the analysis reports.

Synthesis, spectroscopic and antimicrobial studies of Co(II), Ni(II), Cu(II) and Zn(II) complexes derived from benzoic acid bidentate Schiff base ligand

The Schiff base was synthesized by condensation of 2-hydroxy-1-naphthaldehyde with 3- aminobenzoic acid in 1:1 molar ratio. The Schiff base ligand formed complexes with Co (II), Ni (II), Cu (II) and Zn (II) acetate via mechanochemical synthesis. The synthesized compounds were characterized by solubility test, thermal analysis, FT-IR, powder x-ray diffraction, molar conductance measurement, magnetic susceptibility and elemental analysis. The Schiff base has a melting point of 190 oC. The decomposition temperature of complexes was found to be in the range 289 – 302 oC. The Schiff base and its metal (II) complexes were soluble in DMF, DMSO and sparingly soluble in acetonitrile, chloroform, diethyl ether and insoluble in n-hexane which indicate the polar nature of the synthesized compounds. The IR spectral analysis of the free Schiff base shows a band at 1622 cm-1, assigned to v(C=N) stretching vibrations. This band was shifted in the spectra of complexes (1607 – 1633 cm-1), indicating coordination of the Schiff base to the metal ion through the azomethine group. The molar conductance of complexes determined are in the range 9.51 – 14.87 Ohm-1cm2mol-1 which indicate the non-electrolytic nature in DMF. Magnetic susceptibility measurements of Co (II), Ni (II) and Cu (II) complexes exhibit a magnetic moment in the range 1.25 – 3.08 BM. The values correspond to square-planar geometry. The magnetic moment value of Zn (II) complex indicates a diamagnetic behaviour. The elemental analysis of the complexes for C, H and N determined showed that the observed and the calculated percentages of the elements are in good agreement.

Solvo-thermal Assisted-Synthesis; Experimental and Theoretical Characterization; and Biological Evaluations of Azo-Chelator-Ligand Chelates of Fe(II) and Zn(II) ions

Background and Objectives: The resistance of microbes against anti-bacteriological drugs leading to countless deaths and terminal ailments remains a basis for concern. Hence, the main interest of this study was to design, synthesize and report unusual compounds with basic hydrophilic moieties plus hydrophobic functions for anti-bacteriological studies. Materials and Methods: Analytical (melting points, micro-analysis (C. H.N.S) magnetic susceptibility (µeff), molar conductance plus solubility test) methods; spectral (Fourier Transform Infrared(FTIR)), electrospray ionization mass spectrometry (ESI-MS), nuclear magnetic resonance (1H- plus 13C-NMR), electronic(UV-Vis)) measurements; theoretical (DFT) evaluations were utilized for the characterization of the chelator and its chelates. All synthesized compounds were examined for antimicrobial and antioxidant potentials while the chelator was singly evaluated for solvent extractive capacity. Results: A nitrogenous based chelator-ligand, (E)-1-(((4,6-dimethylpyrimidin-2-yl)imino)methyl) naphthalen-2-ol(LH) synthesized through reflux-condensation reaction of 2-amino-4,6-dimethylpyrimidine with 2-hydroxy-1-napthaldehyde was acquired. Further reflux of the chelator-ligand with bivalent ions of iron-sulphate and zinc-acetate salts plus 2,2’-bipyridine resulted into separate bivalent-heteroleptic metallic chelates. The deprotonated nitrogen of the amine moiety and carbon of the carbonyl gave rise to the chelator-ligand with N2O2 chromophore detected around the metallic atom in the chelates. The µeff data plus UV-Vis spectral values of the chelates conformed to 6-coordinate octahedral geometry. All the chelates were high spin and non-ionic in dimethylsulfoxide (DMSO). The antimicrobial and antioxidant screening of the compounds presented moderate to fantastic results, while the metallic extractive proficiency of the chelator showed outstanding extractability for Fe2+ and Zn2+ions with an efficiency of 79.34% and 51.92% correspondingly. Conclusion: All the synthesized compounds are novel and demonstrated prospective biological, plus metallic ions’ extractive potentials required for designs plus isolation of products also for such actions.

Synthesis, Characterization and Biological Screening of Alkylene Dithiophosphate Derivatives of Macrocyclic Complexes of Pb (II)

Alkylenedithiophosphate derivatives of macrocyclic complexes of Pb (II), having N4S4 potential donors, of the general formula, [Pb(L){S2P(OR)2}2] where L=macrocyclic ligands L1, L2, L3, L4 and L5; R= C2H5-, C3H7n or C3H7i have been synthesized from the reaction of [Pb(L)X2(where X= Clˉ, NO3ˉ or CH3COOˉ) with sodium Alkylenedithiophosphate in 1:2 molar ratios in THF. These complexes have been characterized by elemental analysis, molar conductance, molecular weight determinations, IR, 1H, 13C NMR. Macrocyclic Complexes of Pb (II) derivatives have been studied by screening them Aspergillus flavus, Fusarium oxysporum, Alternaria alternata and bacteria like Salmonella typhi and Bacillus subtili. Alkylenedithiophosphate derivatives were found to be more fungitoxic and antibacterial than their corresponding macrocyclic complexes.

SYNTHESIS, BIOLOGICAL STUDY, DNA INTERACTION OF MANNICH BASE METAL COMPLEXES DERIVED FROM BENZAMIDE

Objective: Coordination compounds occur widely in nature and they comprise a large share of current inorganic research. The Mannich reaction is a classic method for the preparation of Mannich bases, namely, β amino compounds, which are heterocyclic. Methods: A novel Mannich base of N-((3,4-dimethoxyphenyl)(2,5-dioxopyrrolidin-1-yl) methyl)benzamide and its coordination complexes with transition metals Mn and Co have been synthesized and characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, UV-Visible, IR, NMR, and Mass spectral studies. Results: Based on the magnetic moment and UV-Visible spectral data, octahedral geometries were assigned for the metal complexes. The metal complexes were screened for antifungal activity. Conclusion: the metal complexes have shown good activity than the ligand. The binding of selected metal complexes with calf thymus DNA was investigated. It is found that the cobalt (II) metal complex of the ligand showed efficient DNA binding ability.

Synthesis, Characterization and in Vitro Antimicrobial Studies of Ternary Mn(II) Complexes with Isatinphenylhydrazone, Glycine and 8-hydroxyquinoline

In our present research work, we have synthesized two ternary metal complexes of Mn(II), complex-I as [Mn(L)(Gly)(Cl)(H2O)] and complex-II as [Mn(L)(Q)(Cl)(H2O)]; where L is Isatinphenylhydrazone (IPH) as primary ligand, whereas glycine (Gly) and 8-hydroxyquinoline (HQ) as secondary ligand in complex-I and II respectively, in 1:1:1 (M : L : Gly or M : L : Q) molar ratios. Above synthesized complexes are employed for characterization using various analytical techniques including elemental analysis, melting point determination, magnetic moment measurements, molar conductance measurements, and spectral techniques (FTIR, UV, 1H NMR) etc. Further, their antimicrobial activities were evaluated against selected bacterial strains i.e., B. subtilis, S. aureus (Gram positive) and P. aeruginosa, E. coli (Gram negative) and fungal strains (T. reesei, A. niger, C. albicans) and found significantly active.

SYNTHESIS, SPECTRAL CHARACTERIZATION AND ANTIMICROBIAL ACTIVITIES OF BIS(CYCLOPENTADIENYL)TITANIUM(IV) COMPLEXES WITH SCHIFF BASES DERIVED FROM5-(SUBSTITUTED ARYL)-2-HYDRAZINO-1, 3, 4-OXADIAZOLE AND INDOLINE-2, 3-DIONE

Titanium(IV) complexes of type[(η5-C5H5)2TiCl(L)] have been synthesized by the reactions of bis(cyclopentadienyl)titanium(IV)dichloride with Schiff bases (LH) derived by the condensation of 5-(substituted aryl)-2-hydrazino-1,3,4-oxadiazole and indoline-2,3-dione in tetrahydrofuranin the presence oftriethylamine. All these complexes are soluble in PhNO2, DMF and DMSO.The complexes were characterized by elemental analyses, electrical conductance, magnetic susceptibility, UV-Vis, IR, 1H NMR, 13C NMR, XRD and SEM spectral techniques. Low molar conductance values indicate that they are non-electrolytes. The spectral data indicate5-coordinate geometry for the complexes.XRD pattern indicate that the complexes have monoclinic crystal system and particle sizes were found 49.36 nm (nano-size). In vitro antifungal activity of synthesized compounds was evaluated against fungi Aspergillusniger, Aspergillusflavus,ColletotrichumfalcatumandIn vitro antibacterial activity was determined by screening the compounds against gram negative (P. aeruginosa, S.typhi) and gram positive (S. aureus and B.subtilis) bacterial strains using minimum inhibition concentration method (MIC) by serial dilution technique. The titanocene(IV) complexes have higher antimicrobial effect than the parent Schiff bases.

Synthesis, Characterization and Antibacterial Activity Study of Cobalt(II), Nickel(II), Copper(II), Palladium(II), Cadmium(II) and Platinum(IV) Complexes with 4-Amino-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazole-3-thione

New transition metal complexes of cobalt(II), nickel(II), copper(II), palladium(II), cadmium(II), and platinum(IV) with bidentate ligand 4-amino-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazole-3-thiol were synthesized and characterized by microelemental analyses (CHNS), Fourier-transform infrared (FT-IR), UV-Visible spectra, molar conductance, magnetic susceptibility and thermal analyses (TG-DSC). The ligand was synthesized by ring closure of potassium-2-(3,4,5-trimethoxybenzoyl) hydrazine carbodithioate with an excess amount of hydrazine, and then was acidified using hydrochloric acid. The ligand was used as Lewis bases to prepare metal complexes through the reaction of ratio (1:2) metal:ligand. The ligand was characterized by 1H-NMR and 13C-NMR and the previously described methods to identify the complexes. The results obtained from spectra and elemental analyses indicated the tetrahedral geometry around Cd(II) ion, square-planar for Cu(II) and Pd(II), and octahedral geometry around Co(II), Ni(II), and Pt(IV). All the metal complexes showed significant antibacterial activity in comparison with the free ligand. The antibacterial test of the platinum(IV) complex showed higher activity than other metal complexes against bacteria Staphylococcus aureus (G-positive) and Escherichia coli (G-negative).

Synthesis, Characterization and Thermogravimetric Study of Some Metal Complexes of Selenazone Ligand Nanoparticles Analogue of Dithizone

A new method for preparing 1,5-diphenylselenocarbazone (selenazone) nanoparticles and their complexes with Pb2+, Cd2+, Co2+, and Ni2+ has been performed using hot methanol solvent. The ligand and its complexes were characterized using FT-IR, UV-Vis, 1H-NMR, 13C-NMR, X-ray powder diffraction (XRD), EI-mass spectrometry, scanning electron microscopy (SEM), HG and flame-atomic absorption spectrophotometer, thermal analysis (TG/DTA), and molar conductance measurements. The molar conductance measurements in all complexes were recorded low values in DMSO, indicating that all the metal complexes were non-electrolytes except the nickel complex that possessed an electrolytic nature. Kinetic and thermodynamic parameters of complexes (A, E, ∆H, ∆S, and ∆G) have been computed using three kinetic models of Coast-Redfern, Broido, and Horowitz-Metzger, that illustrated the decomposition reactions in all steps were nonspontaneous. Thermogravimetric analyses (TG/DTA) were consistent with the atomic spectroscopy data proving that the geometry shape of all the complexes was octahedral.

Synthesis, Characterization Study of Schiff Base Complexes Derived from Ampicillin and 4 Hydroxy3-Methoxy Benzaldehyde

Ampicillin is a derived form of pencillin which is emi synthetic -lactum antibiotic used to treat bladder infections, pneumonia, respiratory infection. schiff’s bases are the most widely studied chelating ligands in coordination chemistry. Recently metal complexes of schiff bases particularly derived from carbonyl compounds base on hetero-cyclic rings have been the centre of attraction in many areas. Present paper brief the synthesis of AHMBL and its transition metal (II) complexes and also the coordination / characterization studies such as magnetic susceptibility, molar conductance, Electronic spectra, Thermal study, FT-IR, H-NMR, XRD, and SEM .