1. Department of Chemistry, Higher Teachers Training College, University of Maroua, Maroua, Cameroon;
2. H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan;
3. Department of Organic Chemistry, Faculty of Science, TWAS Research Unit (TRU) of the University of Yaoundé I, Yaoundé, Cameroon;
4. Department of Chemistry, Faculty of Science, University of Bamenda, Bambili, Cameroon;
5. Multi-Disciplinary Research Lab, Bahria University, Medical & Dental College, Karachi, Karachi, Pakistan;
6. Department of Chemistry, Higher Teachers Training College, University of Yaoundé 1, Yaoundé, Cameroon