1. School of Chemistry and Physics, University of KwaZulu Natal, P/Bag X54001,
Westville, Durban 4000, South Africa
2. Department of Chemistry, School of Science, GITAM Deemed to be University, Hyderabad,
Telangana 502329, India
3. Department of Pharmaceutical Chemistry, Discipline of Pharmaceutical Sciences, College of Health Sciences, University of KwaZulu-
Natal (Westville), Durban-4000, South Africa