Synthesis, characterization, crystal structures and biological activity of molybdenum complexes derived from bis(acetylacetonato) dioxomolybdenum(VI) and Schiff bases

Reaction of bis(acetylacetonato)dioxomolybdenum(VI) with 4-fluoro-2-((pyridin-2-ylmethylene)amino)phenol and 3-methyl-2-((pyridin-2-ylmethylene)amino)phenol, respectively in methanol afforded two new molybdenum complexes [MoO2L1] and [MoO2L2], where L1 and L2 are the dianionic form of 3-(((5-fluoro-2-hydroxyphenyl)amino)(pyridin-2-yl)methyl)pentane-2,4-dione (H2L1) and 3-(((2-hydroxy-6-methylphenyl)amino) (pyridin-2-yl)methyl)pentane-2,4-dione (H2L2). Both complexes have been characterized by elemental analysis, IR, UV-Vis, 1H and 13C NMR spectra. Molecular structures of the complexes have been determined by X-ray crystallography. In the complexes, the ligands coordinated to the Mo atoms via pyridine nitrogen, amino nitrogen, phenolate oxygen, and enolate oxygen atoms. The octahedral coordination of the Mo atoms is furnished by two oxido oxygen atoms. The complexes were evaluated for their antibacterial activities on Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas fluorescens, and antifungal activities on Candida albicans and Aspergillus niger, and gave interesting results.