Coordination behaviour, molecular docking, density functional theory calculations and biological activity studies of some transition metal complexes of bis‐Schiff base ligand

Abstract

ions were synthesized from reaction with Schiff base ligand 4,6-bis((E)-(2-(pyridin-2-yl)ethylidene)amino)pyrimidine-2-thiol (HL) derived from the condensation of 4,6-diaminopyrimidine-2-thiol and 2-(pyridin-2-yl)acetaldehyde. Microanalytical data, magnetic susceptibility, infrared and 1 H NMR spectroscopies, mass spectrometry, molar conductance, powder X-ray diffraction and thermal decomposition measurements were used to determine the structure of the prepared complexes. It was found that the coordination between metal ions and bis-Schiff base ligand was in a molar ratio of 1:1, with formula [M (HL)(H 2 O) 2 ] X n (M = Mn (II), Co (II), Ni (II), Cu (II) and Cd (II), n = 2; Fe (III), n = 3). Diffuse reflectance spectra and magnetic susceptibility measurements suggested an octahedral geometry for the complexes. The coordination between bis-Schiff base ligand and metal ions was through NNNN donor sites in a tetradentate manner. After preparation of the complexes, biological studies were conducted using Gram-positive (B. subtilis and S. aureus) andGram-negative (E. coli and P. aeruginosa) organisms. Metal complexes and ligand displayed acceptable microbial activity against both types of bacteria. KEYWORDS bis-Schiff base ligand, in vitro biological activity, spectroscopy, thermal analysis, transition metal complexes

Synthesis of Some Novel Nanosized Chelates of Anchoring Bisazo Dye 5-[5-(4,6-Dioxo-2-thioxo-hexahydro-pyrimidin-5-ylazo)-naphthalen-1-ylazo]-2-mercapto-1H-pyrimidine-4,6-dione and Their Applications as Antioxidant and Antitumor Agents

“…The charge analysis was used to predict the preferred ligand sites for chelation to the metal ion. It was noted that carbonyl groups’ oxygen atoms (CO), the thione group’s sulfur atom (CS), and the imine group’s nitrogen atom (CN) possessed a high negative atomic charge, making them favorable for coordination with metal ions . Meanwhile, N11 and N12 (azo groups) were not susceptible to chelation because they had high positive and low negative charges, respectively (Table ).…”

“…It was noted that carbonyl groups' oxygen atoms (CO), the thione group's sulfur atom (CS), and the imine group's nitrogen atom (CN) possessed a high negative atomic charge, making them favorable for coordination with metal ions. 89 Meanwhile, N11 and N12 (azo groups) were not susceptible to chelation because they had high positive and low negative charges, respectively (Table 9). All hydrogen atoms had a net positive charge, but due to the presence of an electronegative atom (N), H-amide had a higher positive charge than the other hydrogen atoms.…”

Synthesis, characterization, antimicrobial, and docking study of novel 1‐(furanyl)‐3‐(pyrrolyl)propenone‐based ligand and its chelates of 3d‐transition metal ions

“…The intensity of the peaks related carbonyl heterogeneous group is affected by coordination process by lowering its values as indicated from molar absorptivity values. This variation in epsilon depends upon kind of transition metal and strength of its bonding to ligand L. [47][48][49][50][51] 3.7 | Thermal analyses studies (TG, DTG, and DTA)…”

Schiff base complexes with different metals incorporating derivatives of 3,6‐di‐tert‐butylcarbazole

“…Therefore, the detailed structural investigation of the new model complexes seems to be very important with the view of their potential applications. Both ligands and their complexes have applications in many field of fundamental and applied research including biological applications and pharmaceutical activities, [10][11][12][13] analytical chemistry, [14] catalysis, [15,16] organic synthesis, [17,18] and sensor materials. [19][20][21][22] The general idea of this work was to synthesize a new Schiff base and its metal complexes.…”