Studies on oligomeric metal complexes derived from 2,5-bis((1H-1,2,4-triazol-3-yl)carbamoyl)terephthalic acid

Abstract

Novel oligomer-metal complexes (4a-f) of the ligand 2,5-bis ((1H-1,2,4-triazol-3-yl) carbamoyl) terephthalic acid (3) were prepared using various metal salts viz. Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) and characterized by physicochemical, thermogravimetric, and spectroscopic techniques. Electronic spectral analysis and magnetic measurement studies were taken into account for the geometry of oligomer-metal complexes. Polymeric properties like number average molecular weight (Mn) and degree of polymerization have also been carried out. Ligand (3) was synthesized using pyromellitic diahydride and 1H-1,2,4-triazol-3-amine. Ligand was duly characterized by physicochemical, spectroscopic, and thermogravimetric techniques. All novel synthesized compounds 3 and 4a-f were evaluated for their antibacterial activity against various Gram-positive and Gram-negative bacterial strains. Growth inhibition was compared with the standard drug ciprofloxacin. Antifungal activity was also carried out against different fungal strains. The antifungal drug, ketoconazole, was used as a positive control. The results showed significantly higher antibacterial and antifungal activity of oligomer-metal complexes compared to the ligand.