Structural characterization, spectroscopic studies, biological and antioxidant evaluation of some transition metal complexes

Abstract

Schiff bases are important due to their vivid applications owing to their characteristic properties such as high synthesis flexibility, varied coordinating ability, thermal stability, novel structures, biological activities and medicinal utility. So, different types of Schiff bases have been synthesized by various workers. Schiff base metal complexes have a variety of applicationsin clinical and pharmacological areas. Some of themhaving structural similarities to natural biological substanceshave been used as models in biological macrosystems, radiopharmaceuticalcancer targeting, dioxygen carriers and medicalsubstrates. In the present work, novel tetradentate dianionic Schiff base ligand, N,N′‐bis(2‐carboxyphenylimine)‐2,5‐thiophenedicarboxaldhyde (H2L1) and some first row d‐transition metal chelates (Co(II), Cu(II), Ni(II) and Zn(II)) were synthesized and characterized using variousphysicochemical and spectroscopic methods. The spectroscopic data suggested thatSchiff base ligand coordinates through both deprotonated carboxylic oxygenand imine nitrogen atoms. The free Schiff base and its metal chelates werescreened