Synthesis of Metal Complexes of Substituted Isonicotinohydrazide and their Catalytic and Biological Activities

Abstract

Coordination chemistry has fascinated and inspired chemists all over the world due to an increasing academic, industrial, and biological interest in metal complexes of organic chelating ligands. Among the chelating ligands, Schiff bases have attracted the attention of chemists due to ease of preparation and complexation. Numerous reports showed that a large number of isatin and its Schiff base metal complexes have excellent catalytic activity in a variety of reactions at mild reaction conditions and are used as homogeneous catalysts. Copper-based isatin complexes have found much attention because of their biological relevance. In this study, we report the synthesis of Schiff base metal complexes of substituted isonicotinohydrazide. The Schiff base, (C14H10N4O2) is prepared by condensing isoniazid with isatin. The complexes were synthesized in good yield from easily available metal precursors and characterized by UV-visible and FTIR spectroscopy. The Cu complex shows excellent activity for the C-N coupling reaction of the amination of aryl halides.  All four complexes show better antibacterial activity as compared to their corresponding [M (acac)n] complexes. In addition to this, the Co and Cu complexes such as [Co(C14H10N4O2)3] and Cu(C14H10N4O2)3] respectively show negative growth, towards Fusarium, and Aspergillus i.e. showing antifungal activity. The results were compared with the standard acetyl-acetone complexes of the same metals.