Enhancement of Schiff base biological efficacy by metal coordination and introduction of metallic compounds as anticovid candidates: a simple overview

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jan Mohammad Mir ◽  
Sheikh Abdul Majid ◽  
Aabid Hussain Shalla
Keyword(s):  
Schiff Base ◽  
Metal Complexes ◽  
Antimicrobial Properties ◽  
Biological Evaluation ◽  
Organic Ligands ◽  
Molecular Scaffolds ◽  
Mechanism Of Formation ◽  
Biological Efficacy ◽  
Metallic Compounds ◽  
Azomethine Compounds

Abstract In the prevailing apocalyptic times of coronavirus disease (COVID-19), the whole scientific community is busy in designing anticovid drug or vaccine. Under such a fascination, Schiff bases or azomethine compounds are continuously interrogated for antimicrobial properties. These compounds represent interesting molecular scaffolds of huge medicinal and industrial relevance. In order to update the current literature support of such facts this article introduces the synthetic chemistry, mechanism of formation of a Schiff base, followed by biological efficacy and finally a suitable discussion on the mechanism of respective bioactivity. In most of the studies revealing the biological evaluation of azomethine functionalized frameworks, fascinated results have been recorded in case of azomethine-metal complexes as compared with the free ligands. Also, the CH=N or C=N form of organic ligands have indicated marvellous results. Therefore, in connection with the biological relevance and microbicidal implications of such metallic compounds, this works reviews the current update of microorganism fighting efficacy of azomethine metal complexes along with the introduction of some metallodrugs as excellent candidates having COVID-19 defending potentiality.

Synthesis, Characterization and in vitro Biological Evaluation of a New Schiff Base Derived from Drug and its Complexes with Transition Metal Ions

2018 ◽  
Vol 69 (7) ◽  
pp. 1678-1681
Author(s):  
Amina Mumtaz ◽  
Tariq Mahmud ◽  
M. R. J. Elsegood ◽  
G. W. Weaver
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Metal Ions ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Free Ligand ◽  
Transition Metal Ions ◽  
Biological Evaluation ◽  
Pyridoxal Hydrochloride

New series of copper (II), cobalt (II), zinc (II), nickel (II), manganese (II), iron (II) complexes of a novel Schiff base were prepared by the condensation of sulphadizine and pyridoxal hydrochloride. The ligand and metal complexes were characterized by utilizing different instrumental procedures like microanalysis, thermogravimetric examination and spectroscopy. The integrated ligand and transition metal complexes were screened against various bacteria and fungus. The studies demonstrated the enhanced activity of metal complexes against reported microbes when compared with free ligand.

scholarly journals Synthesis, characterization, and biological evaluation of some 4-((thiophen-2-yl-methylene)amino)benzenesulfonamide metal complexes

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
E. Vijaya Sekhar ◽  
Subhas S. Karki ◽  
Javarappa Rangaswamy ◽  
Mahesh Bhat ◽  
Sujeet Kumar
Keyword(s):  
Escherichia Coli ◽  
Schiff Base ◽  
Aspergillus Niger ◽  
Metal Complexes ◽  
Antimicrobial Properties ◽  
Azomethine Nitrogen ◽  
Diffusion Method ◽  
Sulfa Drugs ◽  
Zone Of Inhibition ◽  
Penicillium Rubrum

Abstract Background Sulfonamides (sulfa drugs) and the metals like mercury, copper, and silver bear antimicrobial properties. The discovery of broad-spectrum antibiotics such as penicillins, cephalosporins, and fluoroquinolones has reduced their use. However, in some instances these drugs are the first-line treatment. The metal-based sulfonamide (e.g., silver sulfadiazine) is considered as first choice treatment in post-burn therapy while the use of silver nanoparticle-cephalexin conjugate to cure Escherichia coli infection explains the synergistic effect of sulfa drugs and their metal conjugates. With growing interest in metal-based sulfonamides and the Schiff base chemistry, it was decided to synthesize sulfonamide Schiff base metal complexes as antioxidant and antimicrobial agent. Results The Fe (III), Ru (III), Co (II), Ni (II), Cu (II), Pd (II), Zn (II), Cd (II), and Hg (II) metal complexes of 4-((thiophen-2-ylmethylene)-amino)-benzenesulfonamide (TMABS) were prepared and studied for thermal stability, geometry, and other electronic properties. The ligand TMABS (Schiff base) and its metal complexes were screened in-vitro for 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and antimicrobial properties against Gram-positive (+ve) Bacillus subtilis (MTCC-441), Staphylococcus aureus (MTCC 7443), Gram-negative (-ve) Escherichia coli (MTCC 40), Salmonella typhi (MTCC 3231), and fungal strains Aspergillus niger (MTCC-1344) and Penicillium rubrum by agar well diffusion method. Results summarized in Tables 3, 4, and 5 represent the inhibitory concentration (IC50) in micromole (μM). The zone of inhibition (ZI) in millimeter (mm) represents antimicrobial properties of TMABS and its metal complexes. Conclusions The synthesized sulfanilamide Schiff base (TMABS) behaved as a neutral and bidentate ligand coordinating with metal ions through its azomethine nitrogen and thiophene sulfur to give complexes with coordination number of 4 and 6 (Fig. 3). The nucleophilic addition of sulfanilamide amino group (–NH2) group to carbonyl carbon (>C=O) of benzaldehyde gave sulfanilamide Schiff base (imine) (Fig. 2). All the metal complexes were colored and stable at room temperature. With IC50 of 9.5 ± 0.1 and 10.0 ± 0.7 μM, the Co, Cu, and Pd complexes appeared better antioxidant than the ligand TMABS (155.3±0.1 μM). The zone of inhibition (ZI) of Hg (28 mm) and Ru complexes (20 mm) were similar to the ligand TMABS (20 mm) against Aspergillus niger (MTCC-1344) as in Figs. 4, 5, and 6. None of the synthesized derivatives had shown better antimicrobial properties than the standard streptomycin sulfate and fluconazole.

scholarly journals Characterization, Molecular Docking, Antimicrobial and Anticancer Studies on 5-Bromo salicylaldehyde-furan-2-yl-methanamine Condensed Schiff Base Rare Earth Metal Complexes

2021 ◽  
Vol 33 (9) ◽  
pp. 2127-2134
Author(s):  
B. Preethi ◽  
R. Jayaprakash ◽  
S. Kutti Rani ◽  
N. Vijayakumar
Keyword(s):  
Schiff Base ◽  
Rare Earth ◽  
Metal Complexes ◽  
Rare Earth Metal ◽  
Earth Metal ◽  
Anticancer Activities ◽  
Spectral Techniques ◽  
Biological Efficacy ◽  
Rare Earth Metal Complexes

This work described the synthesis and characterization of 1-(furan-2-yl) methanamine condensed with 5-bromo-2-hydroxybenzaldehyde Schiff base rare earth metal (Ln3+, Pr3+, Nd3+, Sm3+ and Eu3+) complexes.. They were characterized using relevant spectral techniques and docked against microbial target proteins (1H9Z, 3ZBO) theoretically. The experimental antibacterial and anticancer activities (HeLa, MCF7) of these metal complexes were investigated for biological efficacy. Out of five metal complexes, Pr3+ complex exposed good biological efficacy result in both assays.

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

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.

scholarly journals Synthesis, Characterization and Biological Evaluation of Schiff Base Transition Metal Complexes Derived from 4-Nitrobenzene-1,2-diamine and 5-Chloroisatin

2020 ◽  
Vol 32 (9) ◽  
pp. 2324-2328
Author(s):  
NETRA PAL SINGH ◽  
KAUSHAL KUMAR ◽  
GAJENDRA KUMAR ◽  
ANUROOP KUMAR
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Magnetic Moments ◽  
Biological Evaluation ◽  
Molar Conductance ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Bacteria And Fungi

A series of transition metal complexes of the type [MLX2], where M = Mn(II), Fe(II), Co(II), Ni(II), X = Cl–/CH3COO– and L = Schiff base derived from 4-nitrobenzene-1,2-diamine and 5-chloroisatin have been synthesized and characterized by elemental analysis, molar conductance, IR, UV-visible, magnetic moments measurement, 1H & 13C NMR and mass spectral studies. On the basis of physico-chemical studies and spectral evaluation, an octahedral geometry have been proposed for all metal(II) complexes. The antimicrobial activity of ligand and its metal complexes have been additionally screened against bacteria and fungi. Metal(II) complexes show good activity as compared to ligand towards studied microorganisms and also metal complexes checked for their catalytic properties for benzoylation of phenol.

scholarly journals Synthesis, biological evaluation and corrosion inhibition studies of transition metal complexes of Schiff base

2018 ◽  
Vol 12 (1) ◽  
Author(s):  
Shubham Kashyap ◽  
Sanjiv Kumar ◽  
Kalavathy Ramasamy ◽  
Siong Meng Lim ◽  
Syed Adnan Ali Shah ◽  
...  
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Metal Complexes ◽  
Corrosion Inhibition ◽  
Transition Metal Complexes ◽  
Biological Evaluation ◽  
Inhibition Studies

scholarly journals Synthesis, characterization, in-vitro antimicrobial properties, molecular docking and DFT studies of 3-{(E)-[(4,6-dimethylpyrimidin-2-yl)imino]methyl} naphthalen-2-ol and Heteroleptic Mn(II), Co(II), Ni(II) and Zn(II) complexes

2018 ◽  
Vol 16 (1) ◽  
pp. 184-200 ◽  
Author(s):  
Festus Chioma ◽  
Anthony C. Ekennia ◽  
Aderoju A. Osowole ◽  
Sunday N. Okafor ◽  
Collins U. Ibeji ◽  
...  
Keyword(s):  
Schiff Base ◽  
Molecular Docking ◽  
Metal Complexes ◽  
Drug Targets ◽  
Density Functional ◽  
Radical Scavenging ◽  
Antimicrobial Properties ◽  
Density Functional Theory Calculations ◽  
Elemental Analyses

AbstractHeteroleptic divalent metal complexes [M(L) (bipy)(Y)]•nH2O (where M = Mn, Co, Ni, and Zn; L = Schiff base; bipy = 2,2’-bipyridine; Y = OAc and n = 0, 1) have been synthesized from pyrimidine Schiff base ligand 3-{(E)-[(4,6-dimethylpyrimidin-2-yl)imino]methyl} naphthalen-2-ol, 2,2’-bipyridine and metal(II) acetate salts. The Schiff base and its complexes were characterized by analytical (CHN elemental analyses, solubility, melting point, conductivity) measurements, spectral (IR, UV-vis, 1H and 13C-NMR and MS) and magnetometry. The elemental analyses, Uv-vis spectra and room temperature magnetic moment data provide evidence of six coordinated octahedral geometry for the complexes. The metal complexes’ low molar conductivity values in dimethylsulphoxide suggested that they were non-ionic in nature. The compounds displayed moderate to good antimicrobial and antifungal activities against S. aureus, P. aeruginosa, E. coli, B. cereus, P. mirabilis, K. oxytoca, A. niger, A. flevus and R. Stolonifer. The compounds also exhibited good antioxidant potentials with ferrous ion chelation and, 1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assays. Molecular docking studies showed a good interaction with drug targets used. The structural and electronic properties of complexes were further confirmed by density functional theory calculations.

Sign in / Sign up

Export Citation Format

Share Document