Synthesis, Characterization and Biological Evaluation of Schiff Base (N-4-(thiophene-2-yl-methyleneamino)-2,6-dimethylpyrimidine-4-yl)benzenesulfonamide and its Complexes with Cu(II), Ni(II), Co(II), Fe(II), Mn(II), Zn(II) Ions

Abstract

Two step synthesis of Schiff base ligand and its transition metal complexes was done by condensation reaction. In first step, the drug and aldehyde in equimolar ratio were refluxed for one hour at pH 8-9 in order to get Schiff base ligand. In second step, ligand and metal salts were refluxed for 2 hour. The ligand and Cu(II), Ni(II), Co(II), Fe(II), Mn(II), Zn(II) complexes were characterized by using different instruments like FT-IR, 1H-NMR, 13C-NMR, Mass, Atomic absorption spectrometer, Elemental analyzer, UV-visible spectrophotometer, Evans balance, Conductivitymeter and Thermogravimeter. In vitro antibacterial, antifungal and anti-inflammatory activities were also studied. The synthesized ligand and transition metal complexes were tested against Escherichia coli, Enterobacter aerogenes, Staphylococcus aureus, Bacillus pumilus, Klebsiella oxytoca, Clostridium butyrium, Mucor and Aspergillus niger. These studies demonstrated the enhanced activity of metal complexes against reported bacterial and fungal strains when compared with free Schiff base ligand. The Cu(II) complex recognized as anti-inflammatory agent while the parent drug showed no activity.

Synthesis, Characterization and Bioactivity Study of Few Metal Complexes of Curcumin with 2-(1H-Benzimidazol-2-yl) Aniline

“…The spectrum of L 1 and L 2 appears peaks absorption in (246, 341) nm and 273 nm due to (π→π⃰ ) transition respectively 28 while the peaks at the region 419 nm and 430 nm are because (n→π⃰ ) respectively. 29 In the complexes appeared new absorption peaks in d-d transitions, the Co(II) complex show 551 nm is due to 4 T 1g(F) → 4 T 1g(P) suggesting octahedral geometry of this complex [30][31][32][33] . Ni(II) complex show 570 nm attributed to 3 A 2g(F) → 3 T 1g(F) This is consistent with the octahedral shape of this complexes.…”

Synthesis, Characterization and Biological Evaluation of New Schiff Base Ligand derived from 3-hydroxy-benzaldehyde and p-toluidine and its Divalent Metal Ions

“…where: As shows absorbance of the synthesized sample, Ac is for absorbance of the control sample, Control contain 1 mL of ethanol and 1.85 mL of the DPPH. From percentage inhibition values calculate IC50 values [29], (Table 2).…”

Thiophene‐containing compounds with antimicrobial activity

“…A latter paper in this series featured complexes analogous to 231 that were prepared from ligand 233 (Figure 27) in whose structure sulfadiazine was replaced with sulfisomidine. [ 210 ] With the exception of K. oxytoca , which was less susceptible, the growth of all other bacterial strains was inhibited strongly, especially by the zinc‐derived complex, which appears to be the most active compound in this collection against most bacteria. Fungus A. niger exhibited the same level of growth inhibition as K. oxytoca , while Mucor was more susceptible to the action of complexes of ligand 233 than A. niger .…”