Preparation, Characterization and Evaluation of the Biological Activity of the New Ligand Derived from 2- Mercaptobenzimidazole, a Type of Schiff Bases and its Complexes with some Metal Ions

Abstract

A series of complexes for the new ligand2- { 4-[4- ( 1H-Benzimidazol -2 – yl amino ) –benzyl ] –phenyl imino } – 1,2 – di phenyl- ethanol (BABPPE) were synthesized from reaction ligand(BABPPE) with metal salts, Co (II), Cu (II), Pd (II), Ag (I) and Pt (IV) in ethanol as a solvent. The new ligand (BABPPE) was prepared in two steps: The first step involved the reaction of the compound 2-mercaptobenzimidazole with compound 4,4-di-aniline methane with continuous stirring to give a product (4- (4-amino-benzyl) - phenyl) -benzoimidazole-2-yl-amine) which reacts with benzoin with addition few drops of glacial acetic acid as a catalyst to produce ligand (BABPPE).The ligand and its five complexes were identified by FT- IR, ¹H -¹³C-NMR and UV-Vis. Spectra, molar conductivity, melting points, elemental analysis (CHN), atomic absorption, magnetic sensitivity measurement and FESEM. All complexes prepared with a ratio of (1: 1) (M:L). The above measurements suggested an octahedral geometry for all complexes except the palladium(II) and silver(I) complexes, giving a square planar and tetrahedral, respectively.The biological activity of the ligand and its complexes were evaluated, which showed that they have good activity against the bacteria species under study.

Keywords: Benzimidazole, Schiff bases, Benzimidazole- Schiff bases complexes,biological activity of Benzimidazole .