Synthesis, characterization, molecular modeling and anti-algal activities of a Schiff base and its m+2 complexes

In present work Four new complexes of 2-hydroxy-5-methylbenzaldehyde -N-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)hydrazine have been synthesized with some transition metals, i.e. Ni+2, Cu+2 , Co+2 and Zn+2 in non-aqueous medium. Complexes were characterized by magnetic moment, conductance, scanning electron microscopy (SEM) and spectroscopic investigations including infrared, ultraviolet-visible and atomic absorption spectroscopy. To support experimental characterization, quantum mechanical and molecular mechanical (QM/MM) calculations were performed. Experimental results with the support of QM and MM computations highlighted the proposition about the ligand to be bound to the metal ions in a tridentate manner through its phenolic oxygen, azomethine nitrogen and carbonyl group (C=O). On the basis of experimental and computational results, tetrahedral geometry is proposed for Cu+2 complex and distorted tetrahedral geometry is proposed for Zn+2 complex while octahedral geometries are proposed for Co+2 and Ni+2 complexes. For all compounds, anti-cyanobacterial (algicidal) activity was evaluated against three marine cyanobacteria i.e. Pseudoanabaena lonchoides, Lyngbya contorta, and Spirulina major. It was found that the metal complexes are more potent anti-cyanobacterial agents than the ligand

Synthesis, Characterization, In-Vitro Antimicrobial and Antioxidant Activities of Co+2, Ni+2, Cu+2 and Zn+2 Complexes of 3-(2-(2-hydroxy- 3-methoxybenzylidene)hydrazono)indolin-2-one

Four novel complexes of “3-(2-(2-hydroxy-3-methoxybenzylidene)hydrazono)indolin-2-one” have been synthesized with Co+2, Ni+2, Cu+2 and Zn+2. Physical and analytical techniques including CHN, IR, UV-Vis, AAS, molar conductivity values and magnetic susceptibility data were used to characterize all complexes. The bis Schiff base ligand i.e. 3-(2-(2-hydroxy-3-methoxybenzylidene)hydrazono)indolin-2-one, acted as a tridentate ligand and coordinated through phenolic oxygen, azomethine nitrogen and carbonyl group. Low values of molar conductance suggested the non-electrolyte nature of all complexes. Elemental analysis of complexes indicated the 1:1 metal to ligand mole ratios for [Cu(Inh)(OAc)] and [Zn(Inh)(OAc)] metal complexes and 1:2 metal to ligand mole ratios for [Co(Inh)2] and [Ni(Inh)2] metal complexes. Square planner geometry is proposed for [Cu(Inh)(OAc)] and distorted tetrahedral geometry is proposed for [Zn(Inh)(OAc)] while octahedral geometries are proposed for [Co(Inh)2] and [Ni(Inh)2] metal complexes. Antimicrobial and antioxidant studies were performed for all compounds and it was discovered that the complexes are more potent antibacterial and antifungal agents while the ligand exhibited comparatively more DPPH (1,1-diphenyl-2-picryl-hydrazil) radical scavenging activity than the complexes