Synthesis, spectroscopic characterization and in vitro antibacterial activity studies of Cu(II) complexes derived from 6- hydroxyflavone Schiff bases

Five transition metal complexes, [CuLa] (1), [NiLa] (2), [ZnLa] (3), [CuLb] (4) and [NiLb]. EtOH (5) have been synthesized from reaction of Ni(II), Cu(II) and Zn(II) acetate salts with two Schiff bases, 3-(2-hydroxy-5-methylphenylamino)-1,3-diphenylprop-2-en-1-one (H2La) and 3-(2-hydroxy-5-methylphenylimino)-1-phenylbuten-1-one (H2Lb). On the basis of analytical and spectral data, Schiff base is coordinated to metal as tridentate dianionic ligand via phenolic and enolic oxygens and imine nitrogen. Thermal decomposition of the complexes has been studied by thermogravimetry. The in vitro antibacterial activity of Schiff bases and their complexes has been evaluated against Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria and compared with the standard drugs.

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Synthesis characterization and antibacterial studies of 4-aminoantipyrine schiff’s bases

International Journal of Applied Pharmaceutical Sciences and Research ◽

10.21477/ijapsr.v2i1.6908 ◽

2017 ◽

Vol 2 (01) ◽

pp. 8-14 ◽

Cited By ~ 1

Author(s):

K Sunand ◽

K Vinay Kumar ◽

K Ashwini ◽

P Suresh Kumar ◽

S Vishnu ◽

...

Keyword(s):

Antibacterial Activity ◽

Schiff Bases ◽

Vital Role ◽

Spectroscopic Techniques ◽

Schiff’S Bases ◽

Pharmacological Activities ◽

Schiff's Bases ◽

Ir Spectroscopic

Aim: To synthesize and evaluate 4-aminoantipyrine related schiff’s bases as antibacterial agents. Objective: To synthesize, purify, characterize and evaluate 4-aminoantipyrine. Method: Schiff bases derived from 4-aminoantipyrine play a vital role in biological and pharmacological activities. Knowing the importance of 4-aminoatipyrine schiff bases and their analogues wide varieties of bioactivities like analgesic, antiviral, antipyretic, anti-rheumatic, antimicrobial and anti-inflammatory activities have been widely studied. 4-aminoantipyrine compounds C1 (anisaldehyde), C2 (p-hydroxybenzaldehyde) and C3(vanillin) were prepared by condensation between 4-amino antipyrine and substituted aromatic benzaldehydes. The products were purified by recrystallization by using ethanol, characterized by IR spectroscopy. The N-H stretching in 4-aminoantipyrine is shown at 3430 cm-1 and -3325 cm-1. The -HC=N- stretching is observed in the range of 1508-1504 cm-1 The –OCH3 stretching is found at 1888 cm-1. 4-amino antipyrine related schiff’s bases evaluated their activity as antimicrobials in-vitro by spread plate method against E.coli. Schiff bases have potent antibacterial activity with gram negative bacteria E.coli. Results: Synthesis and characterization of a schiff bases derived from substituted benzaldehydes and 4-aminoantipyrine was evaluated and characterized with the IR spectroscopic techniques and schiff bases have shown potent antibacterial activity against E.Coli.

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Synthesis and antibacterial activity of some Schiff base complexes

Journal of the Serbian Chemical Society ◽

10.2298/jsc0607733n ◽

2006 ◽

Vol 71 (7) ◽

pp. 733-744 ◽

Cited By ~ 42

Author(s):

R. Nair ◽

A. Shah ◽

S. Baluja ◽

S. Chanda

Keyword(s):

Antibacterial Activity ◽

Schiff Base ◽

Metal Complexes ◽

Schiff Bases ◽

Schiff Base Complexes ◽

Ethyl Benzene ◽

Resistant Bacteria ◽

Bacterial Strains ◽

Iron And Zinc

Two Schiff bases were synthesized from raceacetophenone: 1) ADS1 4-ethyl-6-{(E)-1-[(3-nitrophenyl)imino]ethyl}benzene-1,3-diol and 2) ADS3 4-ethyl-6-[(E)-1-{(2-nitrophenyl)imino]ethyl}benzene-1,3-diol. Then their metal complexes were formed. The metals selected for the preparation of complexes were copper, nickel, iron and zinc. Hence, in total 8 metal complexes were synthesized and screened for antibacterial activity against some clinically important bacteria, such as Pseudomonas aeruginosa, Proteus vulgaris, Proteus mirabilis, Klebsiella pneumoniae and Staphylococcus aureus. The in vitro antibacterial activity was determined by the Agar Ditch technique using DMF (polar) and 1,4-dioxane (non polar) as solvents. The Schiff bases showed greater activity than theirmetal complexes; themetal complexes showed differential effects on the bacterial strains investigated and the solvent used, suggesting that the antibacterial activity is dependent on the molecular structure of the compound, the solvent used and the bacterial strain under consideration. The Schiff base ADS3 in the polar solvent DMF showed better antibacterial activity towards the investigated bacterial strains. Amongst the four metals, Zn showed the best antibacterial activity followed by Fe in 1,4-dioxane while Ni followed by Zn and Fe showed the best antibacterial activity in DMF. P. vulgaris was the most resistant bacteria.

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Synthesis and Pharmacological Evaluation of 2-(4-(3 (Substituted Phenyl) Acryloyl) Phenoxy)-N, N Diphenylacetamides

Journal of Drug Delivery and Therapeutics ◽

10.22270/jddt.v10i5.4326 ◽

2020 ◽

Vol 10 (5) ◽

pp. 274-292

Author(s):

Rohit Kumar ◽

Sushil Kumar ◽

Mohammad Asif Khan

Keyword(s):

Antibacterial Activity ◽

Schiff Bases ◽

Biological Activities ◽

Diffusion Method ◽

Gram Positive ◽

Standard Drug ◽

E Coli ◽

Gram Positive Bacteria ◽

Pharmacological Evaluation

Recently a series of Schiff bases of diphenylamine derivatives have been synthesized and evaluated in vitro for their antibacterial activity against pathogenic both Gram-positive bacteria B. subtitles and Gram-negative bacteria E. coli using ciprofloxacin as standard drug at conc. of 50 μg/ml and 100 μg/ml. Literature review revels that chalcones possesses various biological activities like antimicrobial, antiviral, anti-inflammatory, anticancer and sedative etc. Therefore the present study was designed on synthesis and pharmacological evaluation of 2-(4-(3 (Substituted Phenyl) Acryloyl) Phenoxy)-N, N Diphenylacetamides. Target compound was synthesized by reaction of chloroacetylchloride with diphenylamine to afford 2-chloro-N, N-diphenylacetamide which further by reaction with substituted Chalcones and characterized following recrystallization and evaluated for anti-microbial potential through cup-diffusion method. In results, the target compounds were tested for activity against B. Subtilis, E.Coli and C. albicans. The chalcones having the lipophilic 4-chloro group (RKCT2) showed the greatest antimicrobial activity (zone of inhibition 20 & 22 mm against. B. subtilis, E. Coli, C. Albicans respectively. It suggests further researchers to go through anti-microbial evaluations against a more varieties of bacteria and fungi. Keywords: Schiff bases of diphenylamine derivatives, antibacterial activity, Gram-positive bacteria, 2-(4-(3 (Substituted Phenyl) Acryloyl) Phenoxy)-N, N Diphenylacetamides

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Synthesis, Spectroscopic Characterization and Antibactrial Activities of Co(II) Complex of Ofloxacin Drug Mixed with Ascorbic Acid as secondary ligand

BioScientific Review ◽

10.32350/bsr.0303.01 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Ugochukwu Onyenze ◽

I.E. Otuokere

Keyword(s):

Ascorbic Acid ◽

Antibacterial Activity ◽

Melting Point ◽

Spectroscopic Characterization ◽

Diffusion Method ◽

Hydroxyl Groups ◽

Molecular Formula ◽

Filter Paper Disc ◽

Secondary Ligand

Ofloxacin is a quinolone antibiotic that is considered an efficient antibacterial drug with a broad spectrum of activity against anaerobic and aerobic bacteria and has strong antibacterial activity in vitro against many bacteria species by inhibiting their DNA-gyrase. In this study, the synthesis, physicochemical and spectroscopic characterization of Cobalt (II) metal complex with ofloxacin as primary ligand and ascorbic acid as the secondary ligand have been carried out. The complex was prepared by reflux method for four hours in methanol. The complex, with the molecular formula [Co(Ofl)(Asc)], was characterized by its color, solubility, melting point, FTIR, UV/Visible, 1H NMR, and 13C NMR spectroscopy. The color and the melting point suggest that complexation occurred. The Fourier Transform Infrared data for both the primary ligand (Ofl) and the secondary ligand (Asc) acted as tridentate ligands. Ofl coordinated to the Co(II) metal ion via the two carbonyl oxygen atoms and the oxygen atom of the hydroxyl group, whereas Asc coordinated to the metal through the carbonyl and enolic C-2 and C-3 hydroxyl groups. The electronic data suggests octahedral geometry for the complex. The ligands and the novel Co (II) complex were tested for in vitro antibacterial activity against gram-negative and gram-positive bacterial species using the filter paper disc agar diffusion method. Significant antibacterial activities were observed for the complex compared to the ligands. This research will aid in the development of more potent drugs that are resistant to organisms.

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Antibacterial Co(II), Ni(II), Cu(II) and Zn(II) complexes with biacetyl-derived Schiff bases

Journal of the Serbian Chemical Society ◽

10.2298/jsc091026098i ◽

2010 ◽

Vol 75 (8) ◽

pp. 1075-1084 ◽

Cited By ~ 13

Author(s):

Muhammad Imran ◽

Mitu Liviu ◽

Shoomaila Latif ◽

Zaid Mahmood ◽

Imtiaz Naimat ◽

...

Keyword(s):

Antibacterial Activity ◽

Schiff Base ◽

Metal Complexes ◽

Schiff Bases ◽

Bacterial Species ◽

Electronic Spectroscopy ◽

Salmonella Typhi ◽

Schiff Base Ligands ◽

No Donor

The condensation reactions of biacetyl with orthohydroxyaniline and 2-aminobenzoic acid to form bidendate NO donor Schiff bases were studied. The prepared Schiff base ligands were further utilized for the formation of metal chelates having the general formula [ML2.2H2O] where M = Co(II), Ni(II), Cu(II) and Zn(II) and L = HL1 and HL2. These new compounds were characterized by conductance measurements, magnetic susceptibility measurements, elemental analysis, and IR, 1H-NMR and electronic spectroscopy. Both Schiff base ligands were found to have a mono-anionic bidentate nature and octahedral geometry was assigned to all metal complexes. All the complexes contained coordinated water which was lost at 141-160 ?C. These compounds were also screened for their in-vitro antibacterial activity against four bacterial species, namely; Escherichia coli, Staphylococcus aureus, Salmonella typhi and Bacillus subtillis. The metal complexes were found to have greater antibacterial activity than the uncomplexed Schiff base ligands.

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