SYNTHESIS AND CHARACTERIZATION OF BENZOHYDROXAMIC ACID METAL COMPLEXES AND THEIR CYTOTOXICITY STUDY

Hydroxamic acids (RCONHOH) are versatile compounds that constitute a significant biological importance. The syntheses, physico-chemical and characterization of benzohydroxamic acid (BHA) and its metal complexes (VO(IV), Cr(III) and Ni(II)) are reported herein. The metal complexes were synthesized via condensation reaction of BHA and metal salts in 2:1 molar ratio using ethanol as reaction medium. The compounds were characterized by elemental analysis, spectral (infrared, UV-Vis, 1H and 13C NMR,), TGA, magnetic susceptibility as well as molar conductance. The spectral study analysis reveals that all complexes coordinated to the metal via oxygen atoms (O,O) in bidentate manner to form octahedral for [Cr(BHA2).2H2O]H2O, tetrahedral for [Ni(BHA)2] and square pyramidal geometry for [VO(BHA)2]. The molar conductance values suggested that all complexes were non-electrolytes. A cytotoxicity study against HCT116 displayed that VO(IV) has better IC50 values than the parent ligand, BHA but not considered as potent anticancer agents.

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

Asian Journal of Applied Chemistry Research ◽

10.9734/ajacr/2021/v10i130228 ◽

2021 ◽

pp. 40-56

Author(s):

Festus Chioma

Keyword(s):

Condensation Reaction ◽

Test Methods ◽

Molar Conductance ◽

Ionization Mass ◽

Metallic Ions ◽

Bivalent Ions ◽

Iron Sulphate ◽

Methods Analytical ◽

Micro Analysis

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.

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Biological Study of Transition Metal Complexes with Adenine Ligand

Proceedings ◽

10.3390/ecsoc-23-06601 ◽

2019 ◽

Vol 41 (1) ◽

pp. 77 ◽

Cited By ~ 1

Author(s):

Hamad M. I. Hasan ◽

Aaza I. Yahiya ◽

Safaa S. Hassan ◽

Mabrouk M. Salama

Keyword(s):

Metal Complexes ◽

Molar Conductance ◽

Molar Ratio ◽

Biological Study ◽

Ratio Method ◽

Spectroscopic Techniques ◽

Stoichiometric Ratio ◽

Metal Contents ◽

Molar Ratio Method

Adenine complexes were prepared with some of the first series transition metals in a stoichiometric ratio of 1: 2 (Mn+: L), where Mn+ = Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, and Cd2+ ions. The Complexes were characterized by the physicochemical and spectroscopic techniques as electric conductivity, metal contents, IR, UV–Visible, and molar conductance techniques. The stoichiometric ratios of the synthesized complexes were confirmed by using molar ratio method. The dissociation constant of adenine ligand was determined spectrophotometrically. Solvent effect on the electronic spectra of the adenine ligand was examined using solvents with different polarities. The biological activity of adenine ligand and its metal complexes were tested in vitro against some selected species of fungi and bacteria. The results showed a satisfactory spectrum against the tested organisms.

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Synthesis and Spectral Characterization of Mn(II) and Co(II) Complexes with Tetradentate Macrocyclic Ligand

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.23275 ◽

2021 ◽

Vol 33 (9) ◽

pp. 2207-2211

Author(s):

Usha Bansal ◽

Samta Goyal ◽

Swati Agrawal

Keyword(s):

Metal Complexes ◽

Infrared Spectra ◽

Elemental Analysis ◽

Magnetic Moment ◽

Macrocyclic Ligand ◽

Molar Conductance ◽

Octahedral Geometry ◽

Metal Salts ◽

Spectral Studies

Manganese(II) and cobalt(II) complexes were synthesized with [N4] tetradentate macrocyclic ligand using different metal salts i.e. MnCl2, Mn(NO3)2, CoCl2 and Co(NCS)2. The ligand was prepared by condensation of glyoxal and carbahydrazide. All these were characterized by elemental analysis, molar conductance measurements, magnetic moment, IR, mass, electronic and EPR spectral studies. Elemental analysis indicates that the complexes have composition MLX2 where (X = Cl–, NO3 –,NCS–). All the complexes were found to be non-electrolytic in nature so can be formulated as [MLX2]. Infrared spectra of metal complexes suggest that the ligand behaves as tetradentate. On the basis of magnetic moment, electronic and EPR spectral data, all the metal complexes were found to be high spin with octahedral geometry.

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Antitumor and Antimicrobial Potential of Manganese(II), Nickel(II) and Copper(II) Complexes of 4-Methoxy Benzohydrazide Derived Schiff Base Ligand

Letters in Applied NanoBioScience ◽

10.33263/lianbs111.32493260 ◽

2021 ◽

Vol 11 (1) ◽

pp. 3249-3260

Keyword(s):

Schiff Base ◽

Metal Complexes ◽

Schiff Base Ligand ◽

Antimicrobial Activities ◽

Molar Ratio ◽

Gram Positive Bacteria ◽

Ft Ir ◽

Dose Dependent

Herein, we describe the synthesis and characterization of a Schiff base ligand (E)-N'-(2-hydroxybenzylidene)-4-methoxybenzohydrazide (HBMB) and its Mn(II), Ni(II), and Cu(II) metal complexes (C1-C3) respectively. The ligand HBMB was synthesized by reacting condensation of salicylaldehyde and 4-methoxy benzohydrazide in a 1:1 molar ratio. The structure of HBMB and its metal complexes (C1-C3) were evaluated by using UV-Vis, FT-IR, 1H-NMR, mass spectroscopy as well as on the basis of elemental analysis, conductivity measurements, and thermogravimetric techniques (TGA). The synthesized molecules' tumoricidal properties were performed against human breast cancer (MCF-7) and colon cancer (HT 29) cell lines. The biological results indicated that the ligand, HBMB, and metal complexes possess dose-dependent selective cytotoxicity against the tested carcinoma cells. The synthesized compounds were further evaluated for their in vitro antimicrobial activities against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), and fungal strains (Aspergillus niger).

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Preparation, Characterization and Antimicrobial Activity of Schiff Base of (E) - N - (4-(Thiophen-2-ylmethyleneamino) Phenylsulfonyl) Acetamide Metal Complexes

The Open Bioactive Compounds Journal ◽

10.2174/1874847301806010001 ◽

2018 ◽

Vol 6 (1) ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Ahmad S. Abu-Khadra ◽

Ahmed S. Afify ◽

Amr Mohamed ◽

Rabie S. Farag ◽

Hassan Y. Aboul-Enein

Keyword(s):

Metal Complexes ◽

Inductively Coupled Plasma ◽

Uv Spectroscopy ◽

Spectroscopic Studies ◽

Molar Conductance ◽

Molar Ratio ◽

Central Metal Atom ◽

Central Metal ◽

Mass Spectral ◽

Aspergillus Fumigates

Aim:Metal complexes of (E)-N-(4-(thiophen-2-ylmethyleneamino) phenylsulfonyl) acetamide (S.TH) Schiff bases derived from sulfacetamide (N-[4-(amino-phenyl) sulfonil] acetamide) and 2-thiophenecarboxaldehyde were synthesized and characterized.Methods and Results:The synthesized compositions have been characterized using different physico-chemical techniques. The investigation included elemental analysis, melting point measurements, proton NMR, UV spectroscopy, FT-IR, magnetic susceptibility, conductance measurements, mass spectral analysis, and inductively coupled plasma mass spectrometry (ICP-MS) for determining the concentrations of metal ions. The measured values for molar conductance indicated that the majority of the prepared complexes were nonelectrolytes. The biological activity of the prepared compositions has been investigated.Conclusion:Spectroscopic studies suggested that most of the complexes were coordinated in a regular octahedral arrangement where S.TH ligand and the central metal atom were coordinated through two N amino azomethine groups (−HC=N−) and two sulfur atoms of S thiophene rings in 2L:1M molar ratio. Complexes have shown a promising activity upon screening for the antibacterial characteristics, and antifungal (Aspergillus fumigatesandCandida albicans)

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Synthesis, Characterization, and Biological Evaluation of Red-Absorbing Fe(II) Polypyridine Complexes

Inorganics ◽

10.3390/inorganics7010004 ◽

2019 ◽

Vol 7 (1) ◽

pp. 4 ◽

Cited By ~ 20

Author(s):

Johannes Karges ◽

Philippe Goldner ◽

Gilles Gasser

Keyword(s):

Anticancer Agents ◽

Water Solubility ◽

Photophysical Properties ◽

Biological Evaluation ◽

The Body ◽

Ic50 Values ◽

Polypyridine Complexes ◽

Poor Absorption ◽

Micromolar Range

Cancer is known to be one of the major causes of death nowadays. Among others, chemotherapy with cisplatin is a commonly used treatment. Although widely employed, cisplatin is known to cause severe side effects, such as nerve and kidney damage, nausea, vomiting, and bone marrow suppression. Most importantly, a number of cancer tumors are acquiring resistance to cisplatin, limiting its clinical use. There is therefore a need for the discovery of novel anticancer agents. Complementary to chemotherapy, Photodynamic Therapy (PDT) has expanded the range of treatment opportunities of numerous kinds of cancer. Nonetheless, the currently approved PDT photosensitizers (PSs) suffer from major drawbacks, which include poor water solubility or photobleaching, in addition to a slow clearance from the body that causes photosensitivity. Due to these limitations, there is a need for the development of new PDT PSs. To overcome these problems, a lot of research groups around the world are currently focusing their attention towards the development of new metal complexes as PDT PSs. However, most synthesized compounds reported so far show limited use due to their poor absorption in the phototherapeutic window. Herein, we report on the preparation and characterization of three Fe(II) polypyridine complexes (4–6) and evaluate their potential as both anticancer agents and PDT PSs. Very importantly, these compounds are stable in human plasma, photostable upon continuous LED irradiation, and absorb in the red region of the spectrum. We could demonstrate that through additional sulfonic acid groups on the polypyridine ligand being used (bphen: 4,7-diphenyl-1,10-phenanthroline), the water solubility of the complexes could be highly improved, whereas the photophysical properties did not significantly change. One of these complexes (4) shows interesting toxicity, with IC50 values in the low micromolar range in the dark as well as some phototoxicity upon irradiation at 480 and 540 nm against RPE-1 and HeLa cells.

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Synthesis, Spectral Characterization and Biological Evaluation of Schiff Base Metal Complexes Derived from Aniline Derivative

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.22129 ◽

2019 ◽

Vol 31 (9) ◽

pp. 2095-2100

Author(s):

P. Priya ◽

S. Vedanayaki ◽

P. Jayaseelan

Keyword(s):

Schiff Base ◽

Metal Complexes ◽

Magnetic Measurements ◽

Antioxidant Activities ◽

Analytical Data ◽

Biological Evaluation ◽

Molar Conductance ◽

Molar Ratio ◽

Aniline Derivative ◽

Schiff Base Metal Complexes

A new Schiff base ligand (L) N-(4-fluorophenyl)-1-(4-(((4-fluorophenyl)imino)methyl)phenyl)- methaninmine was prepared by the condensation of terephthalaldehyde with 4-fluoroaniline in 1:2 molar ratio. The mononuclear complexes of Co(II), Ni(II), Cu(II) and Zn(II) (1-4) have been synthesized in (2:1) ligand to metal ratio. The composition, geometry and binding sites of ligand with metal complexes were evidenced by various spectral methods like molar conductance, elemental analytical data, magnetic measurements, UV-visible, 1H & 13C NMR, ESI-MS, FT-IR, ESR and thermal analysis. The above studies shows that the ligand is a bidentate and its metal complexes possess an octahedral geometry. Oxidative cleavage of DNA studies of the complexes were monitored by super helix PUC18DNA using a method of agarose gel electrophoresis. Ligand and its metal complexes were screened against gram positive (Staphylococcus aureus), gram negative (Klebsiella pneumoniae) bacterium and fungus (Candida albicans) strains. Antioxidant activities of the metal complexes possess greater activity than ligand.

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Acidic Functionalized Nanobohemite: An Active Catalyst for Methyl Ester Production

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2018-0283 ◽

2019 ◽

Vol 17 (11) ◽

Author(s):

Shokoufe Hosseini ◽

G. R. Moradi ◽

Kiumars Bahrami

Keyword(s):

Active Sites ◽

Free Acid ◽

Reaction Medium ◽

Biodiesel Production ◽

Molar Ratio ◽

Optimal Point ◽

Acidic Catalysts ◽

Boehmite Nanoparticles ◽

Optimized Conditions

Abstract In the biodiesel production, acidic catalysts are ideally suitable for reacting with different oil sources at various free acid levels. On the other hand, the nanocatalysts can easily be propagated in the reaction medium and provide more accessible active sites for reaction. The aim of this work was to synthesize an acidic nanocatalyst based on boehmite nanoparticles then studying it to biodiesel production from soybean oil. Up to now, no reports were found on biodiesel production by this catalyst. After the synthesis and characterization of the catalyst, using response surface methodology (RSM), the optimized conditions for transesterification were 4.87 wt.% for catalyst dosage, 13:1 for the molar ratio of methanol to oil, 60 °C for reaction temperature, and 3 h for reaction time. At the optimal point, the production yield was 99.8 %. After six consecutive use of the catalyst, the yield dropped slightly (88 %). Consequently, the catalyst can be employed efficiently several runs in the production process.

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Synthesis, Characterization and Antibacterial Activity of Schiff Base, 4-Chloro-2-{(E)-[(4-Fluorophenyl)imino]methyl}phenol Metal (II) Complexes

Journal of Chemistry ◽

10.1155/2020/1745236 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

F. K. Ommenya ◽

E. A. Nyawade ◽

D. M. Andala ◽

J. Kinyua

Keyword(s):

Antibacterial Activity ◽

Schiff Base ◽

Metal Complexes ◽

Elemental Analysis ◽

Schiff Base Ligand ◽

Condensation Reaction ◽

Molar Conductance ◽

Diffusion Method ◽

Elemental Analysis Data ◽

Ft Ir

A new series of Mn (II), Co (II), Ni (II), Cu (II), and Zn (II) complexes of the Schiff base ligand, 4-chloro-2-{(E)-[(4-fluorophenyl)imino]methyl}phenol (C13H9ClFNO), was synthesized in a methanolic medium. The Schiff base was derived from the condensation reaction of 5-chlorosalicylaldehyde and 4-fluoroaniline at room temperature. Elemental analysis, FT-IR, UV-Vis, and NMR spectral data, molar conductance measurements, and melting points were used to characterize the Schiff base and the metal complexes. From the elemental analysis data, the metal complexes formed had the general formulae [M(L)2(H2O)2], where L = Schiff base ligand (C13H9ClFNO) and M = Mn, Co, Ni, Cu, and Zn. On the basis of FT-IR, electronic spectra, and NMR data, “O” and “N” donor atoms of the Schiff base ligand participated in coordination with the metal (II) ions, and thus, a six coordinated octahedral geometry for all these complexes was proposed. Molar conductance studies on the complexes indicated they were nonelectrolytic in nature. The Schiff base ligand and its metal (II) complexes were tested in vitro to evaluate their bactericidal activity against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Bacillus subtilis and Staphylococcus typhi) using the disc diffusion method. The antibacterial evaluation results revealed that the metal (II) complexes exhibited higher antibacterial activity than the free Schiff base ligand.

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Synthesis and Characterization of New Lead(II) and Organotin(IV) Complexes of Schiff Bases Derived from Histidine and Methionine

International Journal of Inorganic Chemistry ◽

10.1155/2012/568797 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Har Lal Singh ◽

J. B. Singh

Keyword(s):

Schiff Base ◽

Metal Complexes ◽

Analytical Data ◽

Molar Conductance ◽

Molar Ratio ◽

Azomethine Nitrogen ◽

Spectral Studies ◽

Tetrahedral Geometry ◽

H Nmr ◽

Carboxylate Oxygen

New Schiff base (HL) ligand is prepared via condensation of isatins and amino acids in 1:1 molar ratio. Metal complexes are prepared and characterized by elemental analysis, molar conductance, electronic, infrared, and multinuclear magnetic resonance (1H NMR, 13C NMR, and 119Sn NMR). The analytical data showed that the ligand acts as bidentate toward metal ions via azomethine nitrogen and carboxylate oxygen by a stoichiometric reaction of metal : ligand (1 : 2) to from metal complexes (Pb(II)(L)2 and Bu2Sn(L)2, where L is the Schiff base ligands of histidine and methionine). The conductivity values between 15 and 25 Ω−1cm2 mol−1 in DMF imply the presence of nonelectrolyte species. On the basis of the above spectral studies, distorted octahedral and tetrahedral geometry have been proposed for the resulting organotin(IV) and lead(II) complexes.

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