Monooxovanadium(V) 2-phenylphenoxides: synthesis, characterization, and antimicrobial potential

Abstract

Monooxovanadium(V) complexes of the composition VOCl_{3− n} (L) _n (where L = 2-phenylphenoxide ion; n = 1–3) (1–3) have been synthesized in quantitative yields by the reaction of VOCl₃ with 2-phenylphenol in toluene. The characterization of the complexes has been accomplished by elemental analysis, molar conductance measurements, IR, ¹H-NMR, electronic, mass spectral, and thermal studies. The ligands as well as the complexes have been screened for their in vitro antimicrobial activity against the pathogenic bacteria Escherichia coli and Staphylococcus aureus and fungi Candida albicans, Aspergillus niger, and Fusarium oxysporum by a twofold serial dilution. An increase in the biocidal activity was observed for the vanadium complexes. The minimum inhibitory concentration (MIC) values were 6.25–25 µg mL⁻¹ for complexes, relative to that of the free ligand of 25–50 µg mL⁻¹.

Keywords:

• Monooxovanadium(V) complexes
• 2-Phenylphenol
• Antimicrobial activity

Acknowledgments

One of the authors (M. Thakur) is thankful to the University Grants Commission, New Delhi, India, for providing financial assistance in the form of Junior Research Fellowship. The authors thank Department of Science and Technology (DST), Government of India, New Delhi, for providing financial assistance for FT-IR and UV-Vis Spectrophotometer facility to the department, under its FIST program. The authors wish to thank Sophisticated Analytical Instrument Facility, CDRI, Lucknow, India, for recording the mass spectra. The authors also thank the Sophisticated Analytical Instrument Facility, Punjab University, Chandigarh, for recording ¹H-NMR and elemental analysis data. The authors thank the Department of Bio-sciences, Himachal Pradesh University, Summer Hill, Shimla, for carrying out the antimicrobial studies.