New oxomolybdenum(IV) complexes with adducted monodentate ligands, spectroscopic characterization, DFT calculations, biological and antioxidant activity

Oxomolybdenum(IV) complexes with chemical formula [MoO(ATP)(DIAB)(AMP)] (C1), [MoO(ATP)(DIAB)(Atri)] (C2), [MoO(ATP)(HNQ)(AMP)] (C3) and [MoO(ATP)(HNQ)(Atri)] (C4) have been synthesized and studied using different spectral methods, including atomic absorption, FTIR, UV-Vis., mass spectroscopy, magnetic sensitivity, electrical conductivity, and C.H.N.S. analysis. The ligands were 2-aminothiophenol (ATP), 3,4-diaminobenzoic acid (DIAB), 2-hydroxy-1,4-naphthoquinone (HNQ), 6-amino-2-methylpyridin (AMP), and 3-amino-1,2,4-triazole (Atri). The FTIR spectra confirm (DIAB, AMP, and Atri) were coordinated by amine nitrogen, whereas the (HNQ) ligand was by oxygen, and the (ATP) by nitrogen and sulfur atoms. The υ(S-H) band vanished in comparison to the (ATP) ligand, this demonstrates how Mo(IV) and the sulfur atom. The (HNQ) ligand's oxygen atoms work in tandem with the Mo(IV). Mo(IV) complexes with d2 are paramagnetic. All complexes have been suggested to have an octahedral structure based on computed and experimental evidences. Two Gram-positive and two Gram-negative bacteria were used to test the (ATP) ligand and the produced complexes' activity. The complexes showed an expanded zone of inhibition, indicating that they were more lipophilic than the free (ATP) ligand. Finally, the antioxidant activity of the complexes was tested, and the result showed the following order: Gallic acid ˃ C3 ˃ C2 ˃ C4 ˃ C1 in 60 min. Bull. Chem. Soc. Ethiop. 2025, 39(4), 659-672. DOI: https://dx.doi.org/10.4314/bcse.v39i4.5