Synthesis, spectroscopic characterization and biological evaluation studies of Schiff’s base derived from naphthofuran-2-carbohydrazide with 8-formyl-7-hydroxy-4-methyl coumarin and its metal complexes

Metal complexes of the type ML2, where M = Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II) and L = Schiff’s base derived from the condensation of naphthofuran-2-carbohydrazide with 8-formyl-7-hydroxy-4-methyl coumarin have been synthesized. The chelation of the complexes have been elucidated in the light of analytical, IR, UV–vis, 1H NMR, mass, ESR spectral data, thermal and magnetic studies. The measured molar conductance values indicate that, the complexes are non-electrolytic in nature. The redox behavior of one of the synthesized metal complexes was investigated by cyclic voltammetry. The Schiff’s base and its metal complexes have been screened for their in vitro antibacterial and antifungal activities by MIC method. The DNA cleavage activities of all the complexes were studied by agarose gel electrophoresis method. In addition, the free ligand along with its complexes has been studied for their antioxidant activity.

A new tridentate O, N, O donor Schiff’s base ligand has been synthesized by the condensation of naphthofuran-2-carbohydrazide and 8-formyl-7-hydroxy-4-methyl coumarin. The metal(II) complexes are prepared using the Schiff’s base. All the complexes have been characterized based on the spectral and analytical data. Antimicrobial, antioxidant activities have been carried out for Schiff’s base and its complexes. DNA cleavage activity has been studied for all the complexes. Redox behaviour of Cu(II) complex has been investigated.Figure optionsDownload as PowerPoint slideHighlights
► Synthesis, characterization of a new Schiff base and its metal(II) complexes.
► The Cu(II) complex is of single electron transfer quasi-reversible nature.
► All the complexes have shown promising antimicrobial activities than the ligand.
► Cd(II), Ni(II) and Hg(II) complexes have exhibited good antioxidant activity.
► All the complexes have good ability to cleave the DNA molecule.