Preparation, physicochemical characterization, molecular docking and biological activity of a novel schiff-base and organophosphorus schiff base with some transition metal(II) ions

Abstract

The two synthesis of Schiff base SB (Indole-3-carboxalidene-1-phenylsemicarbazide) and organophosphorus Schiff base OPSB (Indole-3-carboxalidene diphenylphosphate-1-phenylsemicarbazide) have been prepared and characterized by elemental analyses, IR, 1H-NMR, 13C-NMR, UV–Vis and XRD. A series of complexes of the type [M(SB)2Cl2].2H2O and [M(OPSB)Cl.(H2O)2].Cl, where M = Cu(II), Ni(II) and Co(II) have been synthesized and the chemical structures of them were established by magnetic susceptibility, conductance measurements, elemental analyses, IR, UV–Vis. These results suggest that the metal complexes have octahedral geometry. X-ray powder diffraction analysis of ligands and SB complexes indicate that they are crystalline in nature and within nano range. The molecular docking of [Co(OPSB)Cl.(H2O)2].Cl is discussed using MOE software to understand the binding pattern of the investigated compound towards target proteins Bacillus subtilis (PDB ID: 2RHL), Staphylococcus aureus (PDB ID: 4URM), Escherichia coli (PDB ID: 4PRV), Pseudomonas aeruginosa (PDB ID: 4JVI). All compounds have been evaluated for their antimicrobial. The ligands and OPSB complexes showed high antioxidant activity.

Spectroscopic and biological studies of mixed ligand complexes of transition metal (II) ions with chloroquine and ketoprofen

“…2-Compared to free ketoprofen, the vibrational frequencies of the ketonic carbonyl stretches of the complexes remained unchanged, indicating that these functionalities were not involved in the interaction with the metal centers [31]. Due to coordination through the functional group C = N, the band of C=N extending at 1580 cm -1 for chloroquine [32] is moved to 1457-1465 cm -1 . The length of the C=N bond increases as the electron density decreases, slowing the vibration frequency cm -1 in the process.…”

“…Ofloxacin 5 micrograms/disc was used as a reference substance for these bacteria, while Ketoconazole 10 micrograms/disc was used as a reference substance for these fungi. Discs saturated with 10% DMSO were used as a solvent control [25,26].…”

“…Using the well diffusion method [25,26], the ligands and their metal complexes were tested against four different bacterial species (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa), as well as a fungus (Candida albicans), on solid Mollar Henton agar medium. The results are displayed in Table 6.…”