Spectral characterizations and antibacterial effect of 2-(5-R-1H-benzimidazol-2-YL)-4-methyl/bromo-phenols and some metal complexes

2-(5-H/Cl/Me/NO2-1H-benzimidazol-2-yl)-4-Me/Br-phenols (HL1–HL5) were synthesized. HL1 complexes with Cu(NO3)2, AgNO3, Zn(ClO4)2 and; HL4, HL5 complexes with Zn(ClO4)2 were prepared. The structures of the compounds were confirmed on the basis of elemental analysis, molar conductivity, magnetic moment, FT-IR, 1H- and 13C-NMR. Antibacterial activity of the ligands and the complexes were evaluated using the disk diffusion method in dimethyl sulfoxide (DMSO) as well as the minimal inhibitory concentration (MIC) dilution method, against nine bacteria, and the results were compared with penicillin–G and oxytetracycline. While HL1 ligand has considerable antibacterial activity on B. cereus only; it’s Ag(I) complex show antibacterial effect toward almost all the bacteria. It is highly interesting that HL5 and [Zn(HL5)(L5)]ClO4 exhibit considerable high antibacterial activity toward K. pneumoniae, B. cereus, S. epidermidis and B. subtilis. KEY WORDS: Benzimidazole, Phenol, Metal complexes, Antibacterial activity  Bull. Chem. Soc. Ethiop. 2010, 24(3), 391-400

Potentiometric titrations of some mono methyl substituted and 5-keto mono methyl substituted hexadecanoic acids in nonaqueous media

1300-130

Preparation, characterization and antibacterial effect of 2-methoxy-6-(5-H/Me/Cl/NO2-1H-benzimidazol-2-yl)phenols and some transition metal complexes

2-Methoxy-6-(5-H/methyl/chloro/nitro-1H-benzimidazol-2-yl)phenols (HLx; x = 1–4, respectively) ligands and HL1 complexes with Fe(NO3)3, Cu(NO3)2, AgNO3 and Zn(NO3)2 were synthesized and characterized. The structures of the compounds were confirmed based on elemental analysis, molar conductivity, magnetic moment, FT-IR, 1H- and 13C-NMR. The antibacterial activity and minimum inhibitory concentration (MIC) of the free ligands, their hydrochloride salts and the complexes were evaluated using the disk diffusion method in dimethyl sulfoxide (DMSO) and the dilution method, respectively, against 9 bacteria. HL1 and HL3, as well as the Cu(II) and Zn(II) complexes, showed antibacterial activity against Gram-positive bacteria

Bimetallic Cd(II) and Hg(II) complexes of 1,4-bis-(5-H/methyl/chloro-1H-benzimidazol-2-yl)-1,2,3,4-butanetetraols

The bimetallic complexes of 1,4-bis-(5-H/methyl/chloro-1H-benzimidazol-2-yl)-1,2,3,4-butanetetraols (L1–L3) with CdCl2 and HgCl2 were synthesized and characterized by elemental analysis, molar conductivity, as well as IR and 1H-NMR spectroscopy. The ligands coordinate to the metal ion through all of the hydroxyl oxygen atoms as tetradentate in the Hg(II) complexes of L1–L3 and in the Cd(II) complexes of L2 and L3. In theCd2(L1)Cl4 complex, the ligand acts as tetradentate through the benzimidazole nitrogen atoms and the two oxygen atoms of the hydroxyl groups near the imidazole ring

Vanadium(III) chloride complexes of 1,2-bis-(5-H/methyl/chloro/nitro-1H-benzimidazol-2-yl)-1,2-ethanediols

The complexes of 1,2-bis-(5-H/methyl/chloro/nitro-1H-benzimidazol-2-yl)-1,2-ethanediols (L1-L4) with VCl3 were synthesized and characterized by elemental analyses, molar conductivity, FTIR and 1H-NMR spectroscopy. The ligands act as bidentate coordinating through both of the hydroxyl group oxygen atoms in the complexes. The ionic and diamagnetic complexes have the empirical formula [V(L)2]Cl3. The [V(L4)2]Cl3 complex has two isomeric structures according to the 1H-NMR spectral data