1. Department of Chemistry, Federal University Lokoja, Lokoja, Kogi State, Nigeria ;
2. Natural Products/Medicinal Chemistry Unit, Department of Chemistry, University of Ibadan, Ibadan, Nigeria
3. H.E.J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi, Pakistan
4. Pharmaceutical Research Centre, PCSIR Laboratories Karachi, Karachi, Pakistan