1. Department
of Chemistry, UGC Centre of Advance Study-I, Guru Nanak Dev University, Amritsar, Punjab 143005, India
2. Division
of Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
3. Department
of Chemistry, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 701, South Africa
4. Rega
Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium