Synthesis, characterization & biological studies of Mn(II), Fe(III) and Co(II) complexes of (Z)-1, 5-dimethyl-4-(2-(2-oxopropylidene) hydrazinyl)-2-phenyl-1H-pyrazol-3(2H)-one

Mn(II), Fe(III) and Co(II) complexes of the hydrazone derived from 4-aminoantipyrine and ethylacetoacetate has been synthesized and characterized by elemental analysis, electrical conductance in non-aqueous solvents, spectroscopic data including FT-IR, electronic, Electrospray ionization mass and Mossbauer as well as by thermogravimetric analysis. In all the complexes, the compound acts as neutral bidentate ligand, coordinating through the pyrazolone oxygen and azomethine nitrogen. A high spin octahedral geometry assigned to the Mn(II), Fe(III) and Co(II) complexes were further confirmed by magnetic moment data. Elemental analysis showed that Fe(III) complex composed of metal and ligand in a molar ratio of 1:1 whereas metal to ligand ratio in Mn(II) and Co(II) complexes were found to be 1:2. The complexes have also been screened for their antimicrobial and antioxidant activity. The MTT assay of the Co(II) complex was also carried out. Antiviral docking studies of the ligand was done against the native and mutant HIV-1 Reverse Transcriptase protein (PDB ID: 1RT2 and 1FK9) and the ligand showed significant inhibitory activity against both forms of the protein. (C) 2019 Elsevier B.V. All rights reserved.