Synthesis, characterization, crystal structures, and antibacterial activity of oxidovanadium(V) complexes with mixed ligands

Two new oxidovanadium(V) complexes, [VO(L)(Ehp)] (I) and [VO(L)(Aha)] (II), where L is the dianionic form of 4-bromo-N'-(4-oxopentan-2-ylidene)benzohydrazide (H2L), Ehp is the monoanionic form of 2-ethyl-3-hydroxy-4H-pyran-4-one (HEhp), and Aha is the monoanionic form of acetohydroxamic acid (HAha), were prepared and characterized by elemental analysis, infrared and electronic spectra, and H-1 NMR spectra. Structures of the complexes were further confirmed by single crystal X-ray diffraction (CIF files CCDC nos. 1477847 (I), 1477850 (II)). H2L coordinates to the V atom through the two enolic O atoms and the imino N atom. The ligands Ehp and Aha coordinate to the V atoms through bidentate OO donor set. The V atoms of the complexes are in octahedral coordination, with the oxo group furnished the octahedral geometry. The complexes show effective antibacterial activity against Bacillus subtilis.