Suman Malik

Synthesis, Characterization, and Biological Evaluation of Some 3d-Metal Complexes of Schiff Base Derived from Xipamide Drug

The present paper deals with the synthesis and characterization of metal complexes of Schiff base derived from xipamide, a diuretic drug. The bidentate ligand is derived from the inserted condensation of 5-aminosulfonyl-4-chloro-N-2,6-dimethyl phenyl-2-hydroxybenzamide (Xipamide) with salicylaldehyde in a 1 : 1 molar ratio. Using this bidentate ligand, complexes of Hg(II), Zn(II), and VO(IV) with general formula ML2 have been synthesized. The synthesized complexes were characterized by several techniques using molar conductance, elemental analysis, magnetic susceptibility, FT-IR spectroscopy, electronic spectra, mass spectra, and particle size analysis. The elemental analysis data suggest the stoichiometry to be 1 : 2 [M : L]. All the complexes are nonelectrolytic in nature as suggested by molar conductance measurements. Infrared spectral data indicate the coordination between the ligand and the central metal ion through deprotonated phenolic oxygen and azomethine nitrogen atoms. Spectral studies suggest tetrahedral geometry for Hg(II), Zn(II) complexes, and square pyramidal geometry for VO(IV) complex. The pure drug, synthesized ligand, and metal complexes were screened for their antifungal activities against Aspergillus niger and Aspergillus flavus. The ligand and its Hg(II) and VO(IV) complexes were screened for their diuretic activity too.

3D-Metal Complexes Derived from Proton Pump Inhibitors-Synthesis, Characterization and Biological Studies

Complexes of lansoprazole 2[[[[3-methyl, 4-(2′,2′,2′-trifluoro-ethoxy)]-2-pyridinyl] methyl]sulfonyl]–1H–benzimidazole (LAN) with chlorides of Co(II), Ni(II), Cu(II), Mn(II) and Zn(II) were synthesized. LAN is a weak base and it can form several complexes with transition and non-transition metal ions. It should be noticed that the reaction of all the metal salts yielded bis(ligand) complexes of the general formula [ML2(H2O)2] and [ML2] (M = Co, Ni, Cu, Mn and Zn). The complexes were characterized by elemental analysis, molar conductivity, magnetic susceptibility measurements, IR, 1H-NMR, UV-visible spectral studies, ESR, SEM, x-ray diffraction, TGA and mass spectra. In all the complexes ligand is coordinated by participation of the pyridine nitrogen of the benzimidazole ring and sulphonyl group. Electronic spectra and magnetic susceptibility reveal octahedral geometry for Mn(II), Co(II), Ni(II) and Cu(II) complexes and tetrahedral for Zn(II) complex. The antimicrobial activity of the ligand and its complexes against bacteria Pseudomonas aeruginosa, Staphylococcus aureus and fungi Aspergillus niger and Aspergillus flavous were investigated. The effect of metals on the antimicrobial activity of the ligand has been discussed.

Complexation and Antimicrobial Studies of Some Divalent Metal Chelates

Metal chelates of Ni(II) and Cu(II) with the ligand 5-acetamido-1,3,4-thiadiazole-2-sulphonamide have been synthesized. The isolated compounds have been characterized by elemental analysis, molar conductivity, magnetic moment, electronic and IR spectral studies. The analytical data reflects the metal to ligand stoichiometry to be 1: 2. The conductivity data of the complexes also suggests their non-electrolytic nature. The stability constants and free energy change for the complexes have been calculated.. Ligand and their complexes have been screened for their biological activity and the data show good activity of these complexes and ligands.