Synthesis, in vitro biological evaluation and in silico molecular docking studies of novel β-lactam-anthraquinone hybrids

Schiff bases from 2-aminoanthraquinone have been prepared by reaction with aldehydes and used to prepare novel beta-lactam-anthraquinone hybrids via [2+2] ketene-imine cycloaddition (Staudinger reaction) reaction. In vitro antibacterial studies of all synthesized compound were carried out against three gram-positive strains Staphylococcus aureus (Methicillin-resistant strain), Enterococcus faecium (Vancomycin-resistant strain) and Bacillus subtilis, and two gram-negative strains Escherichia coli and Pseudomonas aeruginosa. These compounds were further evaluated for their in vitro antifungal activity against Candida albicans, Aspergillus niger and Trichophyton mentagrophytes. Hybrid compounds showed moderate to excellent antibacterial and antifungal activities. Surprisingly, among the tested compounds, some of them revealed equal antibacterial and antifungal properties and even better than standards. In addition, results demonstrated that the new hybrids are very promising antibacterial agents against resistant strains. Also molecular docking studies were carried out by Autodoc software. Penicillin-binding protein 2a (PDB ID: 1VQQ) from methicillin-resistant Staphylococcus aureus strain used as a target which good binding interactions were observed.