Synthesis, characterization, and antimicrobial activity of oxovanadium(IV)hydroxamate complexes

Abstract

Vanadium(IV) complexes, [VO(acac)(HL^1,2)] and [VO(HL^1,2)₂] (I–IV) (where acac = (); HL^1,2 = R′C(O)NHO⁻, R′ =–CH₂OC₆H₅ and–CH=CHC₆H₅), have been synthesized by reaction of VO(acac)₂ with the potassium salt of phenoxyacetohydroxamic and cinnamohydroxamic acids and characterized by elemental analyses, molar conductivity, magnetic measurements, molecular weight determinations, IR, electronic, mass spectral, and electrochemical studies. From the spectroscopic studies, O,O coordination of hydroxamate ligands and a square-pyramidal geometry for the complexes has been proposed. The antibacterial activities of VO(acac)₂, the precursor, the free ligands, and the synthesized oxovanadium(IV)hydroxamate complexes against six bacteria have been assayed by the minimum inhibitory concentration method. The complexes exhibit antimicrobial activities comparable to the standard drug streptomycin.

Keywords:

• Oxovanadium(IV) complexes
• Potassium phenoxyacetohydroxamate
• Cinnamohydroxamate
• Spectral studies
• Antimicrobial activity

Acknowledgments

Meena Kumari is grateful to the University Grant Commission, New Delhi for providing financial support in the form of Major Research Project F. No.33-295 / 2007 (SR) dated 28.02.2008. The authors are grateful to Prof S. Tabassum, Aligargh Muslim University Aligargh for his assistance in providing electrochemical data. The authors thank the Department of Science & Technology (DST), Government of India, New Delhi for providing financial assistance for FT-IR and UV-Vis Spectrophotometer facility, Sophisticated Analytical Instrument Facility of CDRI, Lucknow, Punjab University Chandigarh for recording mass spectra, elemental analysis data and magnetic susceptibility measurements, respectively.