Reactions of Group VIB metal carbonyls with two novel rigid macrocyclic Schiff base ligands incorporating acridine inter-crossing group

Abstract

Two new rigid macrocyclic Schiff base ligands incorporating acridine inter-crossing group [1,1′-(acridine-3,6-diylbis(azaneylylidene))bis(methaneylylidene))bis(naphthalen-2-ol), L1, and N,N'-(acridine-3,6-diyl)bis(1-(quinolin-2-yl)methanimine), L2, were synthesized and fully characterized. The X-ray single crystal analysis of L1 explored that the compound crystallized in a monoclinic crystal system with a space group P21/c. The compound was crystalized with five water molecules. Interestingly, L1 occurred as a double zwitterion, where the hydrogen of the OH group of the hydroxynaphthalene transferred to the azomethine nitrogen to form NH+ and O− moieties with the presence of hydrogen bonding between them. Hirshfeld surface analysis of the L1 was also investigated. Reactions of the two ligands with the Group VIB metal carbonyls in air were investigated. In order to characterize the novel compounds, various analytical and spectroscopic methods were used. The analysis revealed that the complexes were formed as oxo derivatives with unique structural features. The presented compounds conducted fluorescence quenching investigations, viscosity evaluations, antimicrobial and antioxidant properties. It was concluded that the binding interaction with DNA was electrostatic binding mode rather than intercalative mode. Molecular docking of L1 and its complexes were investigated versus three macromolecular receptors (PDB: 4BJP, 1BQB and 1BNA). These targets were selected to compare the experimental biological data with the results of the docking analysis.