Syntheses, crystal structures, and antibacterial activity of oxidovanadium(V) and dioxidomolybdenum(VI) complexes derived from N′-(2-hydroxy-4-methoxybenzylidene)isonicotinohydrazide

N'-(2-Hydroxy-4-methoxybenzylidene)isonicotinohydrazide (H2L) was used as ligand to prepare new oxidovanadium(V) complex [VOL(OMe)(MeOH)] (1) and new dioxidomolybdenum(VI) complex [MoO2L(MeOH)] (2). The two complexes were characterized on the basis of their FT-IR, UV, H-1 NMR spectra, and molar conductivity. Crystal structures of 1 and 2 have been determined by single crystal X-ray diffraction techniques, which show that the hydrazone ligand coordinates as a di-valent anion with its tridentate O, N, O donors derived from the enolic and phenolic oxygen and azomethine nitrogen. The V ion in 1 is in octahedral coordination, with three donors of the hydrazone ligand and with the remaining sites furnished by one deprotonated methanol oxygen, one neutral methanol oxygen, and one oxo oxygen. The Mo ion in 2 is in octahedral coordination, with three donors of the hydrazone ligand and with the remaining sites furnished by one neutral methanol oxygen and two oxo oxygen atoms. Molecular structures of 1 and 2 are stabilized by hydrogen bonds. The hydrazone and the complexes were screened for their antimicrobial activity and showed good activity.