1. Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box: 2457, Riyadh 11451, Saudi Arabia
2. Research Center, College of Pharmacy, King Saud University, P.O. Box: 2457, Riyadh 11451, Saudi Arabia
3. Department of Chemistry, Nelson Mandela University, PO Box 77000, Port Elizabeth 6031, South Africa